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Hornung TPP, Koonjoo N, Shen S, Longarino FK, Keenan KE, Yan S, Bortfeld TR, Rosen MS. Breast Coil Optimization for Low Field MRI and Future MR-Guided Proton Therapy. IEEE Trans Biomed Eng 2025; 72:1750-1765. [PMID: 40030667 DOI: 10.1109/tbme.2024.3520895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/05/2025]
Abstract
OBJECTIVE Ultra-low field (ULF) magnetic resonance imaging of the breast and chest wall was conducted using optimized radiofrequency (RF) coil designs, and to explore future applications in MR-guided proton therapy (MRgPT), simulation studies of a pencil proton beam trajectory in low and ULFs were conducted. METHODS The focus in this study is the RF coil design, which is approached as a multi-objective optimization (MOO) problem and solved using a defined performance metric and Pareto optimality formalism. Our winding pattern algorithm was developed to simultaneously optimize the coil's magnetic field homogeneity, signal-to-noise ratio (SNR), and magnetic field drop-off into the chest wall for improved imaging of organs-at-risk. Five single-channel, transmit/receive breast-shaped RF coils were constructed. 3D phantom MRI was performed at 6.5 mT to evaluate field homogeneity and SNR. The first in vivo breast imaging at 6.5 mT was conducted. Monte Carlo simulations were employed to investigate the effects of copper wire and static field strengths on proton beam deflection. RESULTS The MOO method was validated - the observed field homogeneity, the relative ratio of SNRs, and the MRI chest signal agreed for all coils with the simulations. In vivo imaging revealed good breast tissue contrast and clear heart visualization. Our findings indicated that a ∼50 mT field with ∼10 mT/m gradient strengths can minimize proton beam deflection, achieving ∼2 × 2 × 5 mm3 spatial resolution within minutes, supporting the clinical feasibility of MRgPT. CONCLUSION Our MOO method can be used to design breast coils that meet a wide range of imaging requirements..
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Wang H, Guo J, Zhang Y, Fu Z, Yao Y. Closed-loop rehabilitation of upper-limb dyskinesia after stroke: from natural motion to neuronal microfluidics. J Neuroeng Rehabil 2025; 22:87. [PMID: 40253334 PMCID: PMC12008995 DOI: 10.1186/s12984-025-01617-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2024] [Accepted: 03/27/2025] [Indexed: 04/21/2025] Open
Abstract
This review proposes an innovative closed-loop rehabilitation strategy that integrates multiple subdomains of stroke science to address the global challenge of upper-limb dyskinesia post-stroke. Despite advancements in neural remodeling and rehabilitation research, the compartmentalization of subdomains has limited the effectiveness of current rehabilitation strategies. Our approach unites key areas-including the post-stroke brain, upper-limb rehabilitation robotics, motion sensing, metrics, neural microfluidics, and neuroelectronics-into a cohesive framework designed to enhance upper-limb motion rehabilitation outcomes. By leveraging cutting-edge technologies such as lightweight rehabilitation robotics, advanced motion sensing, and neural microfluidic models, this strategy enables real-time monitoring, adaptive interventions, and personalized rehabilitation plans. Furthermore, we explore the potential of closed-loop systems to drive neural plasticity and functional recovery, offering a transformative perspective on stroke rehabilitation. Finally, we discuss future directions, emphasizing the integration of emerging technologies and interdisciplinary collaboration to advance the field. This review highlights the promise of closed-loop strategies in achieving unprecedented integration of subdomains and improving post-stroke upper-limb rehabilitation outcomes.
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Affiliation(s)
- Honggang Wang
- State Key Laboratory of Robotics and System, Harbin Institute of Technology, Harbin, 150001, China
| | - Junlong Guo
- State Key Laboratory of Robotics and System, Harbin Institute of Technology, Harbin, 150001, China
| | - Yangqi Zhang
- State Key Laboratory of Robotics and System, Harbin Institute of Technology, Harbin, 150001, China
| | - Ze Fu
- Institute of Biological and Medical Technology, Harbin Institute of Technology (Weihai), Weihai, 264200, China
| | - Yufeng Yao
- State Key Laboratory of Robotics and System, Harbin Institute of Technology, Harbin, 150001, China.
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Fujita S, Hagiwara A, Kamagata K, Aoki S. Clinical Neuroimaging Over the Last Decade: Achievements and What Lies Ahead. Invest Radiol 2025:00004424-990000000-00324. [PMID: 40239043 DOI: 10.1097/rli.0000000000001192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/18/2025]
Abstract
ABSTRACT The past decade has witnessed notable advancements in clinical neuroimaging facilitated by technological innovations and significant scientific discoveries. In conjunction with Investigative Radiology's 60th anniversary, this review examines key contributions from the past 10 years, emphasizing the journal's most accessed articles and their impact on clinical practice and research. Advances in imaging technologies, including photon-counting computed tomography, and innovations in low-field and high-field magnetic resonance imaging systems have expanded diagnostic capabilities. Progress in the development and translation of contrast media and rapid quantitative imaging techniques has further improved diagnostic accuracy. Additionally, the integration of advanced data analysis methods, particularly deep learning and medical informatics, has improved image interpretation and operational efficiency. Beyond technological developments, this review highlights basic neuroscience findings, such as the discovery and characterization of the glymphatic system. These insights have provided a deeper understanding of central nervous system physiology and pathology, bridging the gap between research and clinical applications. This review integrates these advancements to provide an overview of the progress and ongoing challenges in clinical neuroimaging, offering insights into its current state and potential future directions within the broader field of radiology.
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Affiliation(s)
- Shohei Fujita
- From the Department of Radiology, Juntendo University, Tokyo, Japan (S.F., A.H., K.K., S.A.); Department of Radiology, The University of Tokyo, Tokyo, Japan (S.F.); Department of Radiology, The University of Tokyo, Tokyo, Japan (A.H.); Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA (S.F.); and Department of Radiology, Harvard Medical School, Boston, MA (S.F.)
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Li L, He Q, Wei S, Wang H, Wang Z, Yang W. Exploring the potential performance of 0.2 T low-field unshielded MRI scanner using deep learning techniques. MAGMA (NEW YORK, N.Y.) 2025; 38:253-269. [PMID: 39964601 DOI: 10.1007/s10334-025-01234-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2024] [Revised: 01/16/2025] [Accepted: 02/03/2025] [Indexed: 03/19/2025]
Abstract
OBJECTIVE Using deep learning-based techniques to overcome physical limitations and explore the potential performance of 0.2 T low-field unshielded MRI in terms of imaging quality and speed. METHODS First, fast and high-quality unshielded imaging is achieved using active electromagnetic shielding and basic super-resolution. Then, the speed of basic super-resolution imaging is further improved by reducing the number of excitations. Next, the feasibility of using cross-field super-resolution to map low-field low-resolution images to high-field ultra-high-resolution images is analyzed. Finally, by cascading basic and cross-field super-resolution, the quality of the low-field low-resolution image is improved to the level of the high-field ultra-high-resolution image. RESULTS Under unshielded conditions, our 0.2 T scanner can achieve image quality comparable to that of a 1.5 T scanner (acquisition resolution of 512 × 512, spatial resolution of 0.45 mm2), and a single-orientation imaging time of less than 3.3 min. DISCUSSION The proposed strategy overcomes the physical limitations of the hardware and rapidly acquires images close to the high-field level on a low-field unshielded MRI scanner. These findings have significant practical implications for the advances in MRI technology, supporting the shift from conventional scanners to point-of-care imaging systems.
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Affiliation(s)
- Lei Li
- Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Qingyuan He
- Department of Radiology, Peking University Third Hospital, Beijing, China
| | - Shufeng Wei
- Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing, China
| | - Huixian Wang
- Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing, China
| | - Zheng Wang
- Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing, China
| | - Wenhui Yang
- Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing, China.
- University of Chinese Academy of Sciences, Beijing, China.
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Longarino FK, Shen S, Koonjoo N, Hornung TP, Jimenez RB, Mehanna EK, Burge JT, Wilson Z, Keenan KE, Bortfeld TR, Rosen MS, Yan S. Ultra-low field magnetic resonance breast imaging in prone and seated positions for radiation therapy. Phys Imaging Radiat Oncol 2025; 34:100758. [PMID: 40231222 PMCID: PMC11994385 DOI: 10.1016/j.phro.2025.100758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2024] [Revised: 03/22/2025] [Accepted: 03/24/2025] [Indexed: 04/16/2025] Open
Abstract
Background & purpose The aim of this first-in-human study was to investigate the potential of ultra-low field (ULF) magnetic resonance imaging (MRI) at 6.5 mT for breast imaging in healthy female participants in prone and seated positions for radiation therapy, especially compact proton therapy systems. Materials & methods An experimental setup for breast imaging in prone and seated positions utilizing an ULF MRI scanner and a conical RF coil was developed. ULF MR images of the left breast of ten healthy women were acquired in prone and seated positions using a 3D balanced steady-state free precession sequence without the use of contrast agents. The visibility of the breast outline, chest wall, and cardiac silhouette in prone and seated position ULF breast MR images was evaluated by two radiation oncologists (ROs) and two radiation therapists (RTTs), respectively. Results ULF breast MRI obtained at 6.5 mT can show breast outline, chest wall, and cardiac silhouette in prone and seated positions. ULF prone/seated images were found to be acceptable by the ROs (RTTs) for treatment planning (setup) purposes in 100%/95% (95%/85%) of cases for breast outline visibility, in 70%/50% (75%/70%) of cases for chest wall visibility, and in 65%/65% (0%/10%) of cases for cardiac silhouette visibility. Conclusions This proof-of-concept study demonstrated that breast imaging is feasible in prone and seated positions utilizing ULF MRI and partially suitable for treatment planning and setup in proton therapy. Yet an increased spatio-temporal resolution is required for applications to MRI-guided proton therapy. ULF MRI may enable position monitoring and adaptive treatment procedures in radiation therapy.
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Affiliation(s)
- Friderike K. Longarino
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, USA
- Clinical Cooperation Unit Translational Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany
- Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Sheng Shen
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, USA
- Harvard Medical School, Boston, USA
| | - Neha Koonjoo
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, USA
- Harvard Medical School, Boston, USA
| | - Torben P.P. Hornung
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, USA
- Department of Physics, ETH Zürich, Zürich, Switzerland
| | - Rachel B. Jimenez
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, USA
- Harvard Medical School, Boston, USA
| | - Elie K. Mehanna
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, USA
| | - John T. Burge
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, USA
| | - Zoelle Wilson
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, USA
| | | | - Thomas R. Bortfeld
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, USA
- Harvard Medical School, Boston, USA
| | - Matthew S. Rosen
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, USA
- Harvard Medical School, Boston, USA
| | - Susu Yan
- Department of Radiation Oncology, Massachusetts General Hospital, Boston, USA
- Harvard Medical School, Boston, USA
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Chen YA, Mathur S, Lin A, Knopp E, Rosen MS, Bharatha A. Tips and challenges for clinical use and interpretation of low field portable MRI in neuroimaging. Emerg Radiol 2025; 32:279-289. [PMID: 39976637 DOI: 10.1007/s10140-025-02323-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2024] [Accepted: 02/07/2025] [Indexed: 04/08/2025]
Abstract
Low field portable MRI (LF pMRI) is a new imaging tool that holds promise in offering a safe, cost-effective, point-of-care imaging solution in neuroimaging. There are however unique interpretive challenges and operational factors and limitations in its implementation in clinical practice. This paper aims to provide a comprehensive guide on the tips and tricks of interpreting LF pMRI, specifically the Hyperfine Swoop® MRI system, which operates at 0.064 T and is currently the only FDA and Health Canada approved LF pMRI system. This paper explores the operational aspects and interpretation challenges of low-field MRI, such as patient positioning, protocol selection, and the appearance of artifacts and common pathologies. Using illustrative examples, we aim to guide current and future operators of LF pMRI to optimize performance, provide accurate diagnoses, and avoid common pitfalls.
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Affiliation(s)
- Yingming Amy Chen
- Division of Neuroradiology, Department of Medical Imaging, St. Michael's Hospital, Unity Health, University of Toronto, 3rd Floor Cardinal Carter South, 30 Bond Street, Toronto, ON, M5B 1W8, Canada.
| | - Shobhit Mathur
- Division of Neuroradiology, Department of Medical Imaging, St. Michael's Hospital, Unity Health, University of Toronto, 3rd Floor Cardinal Carter South, 30 Bond Street, Toronto, ON, M5B 1W8, Canada
| | - Amy Lin
- Division of Neuroradiology, Department of Medical Imaging, St. Michael's Hospital, Unity Health, University of Toronto, 3rd Floor Cardinal Carter South, 30 Bond Street, Toronto, ON, M5B 1W8, Canada
| | | | - Matthew S Rosen
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Aditya Bharatha
- Division of Neuroradiology, Department of Medical Imaging, St. Michael's Hospital, Unity Health, University of Toronto, 3rd Floor Cardinal Carter South, 30 Bond Street, Toronto, ON, M5B 1W8, Canada
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Groteklaes A, Dresbach T, Born M, Mueller A, Sabir H. Case Report: Ultralow-field portable MRI improves the diagnosis of congenital hydrocephalus. Front Pediatr 2025; 13:1463314. [PMID: 40083429 PMCID: PMC11903728 DOI: 10.3389/fped.2025.1463314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2024] [Accepted: 02/13/2025] [Indexed: 03/16/2025] Open
Abstract
Introduction Congenital hydrocephalus is an increasing condition both in high as in low and middle income countries. Main causes include aqueductal stenosis, neonatal central nervous system infections, intracranial hemorrhage, malformations and tumors. Investigation of its etiology should include magnetic resonance imaging (MRI) to detect especially pathologies of the fossa cranii posterior. However, MRI is not available to every infant presenting with congenital hydrocephalus especially in those countries with the highest prevalence. New portable ultralow-field MRI (ULF) allows low resource and bedside imaging and thus widens the access to MRI for those infants. This study presents two cases of newborns with congenital hydrocephalus who underwent ULF scanning revealing a tumor of the fossa cranii posterior as cause of hydrocephalus. This study shows that ULF scanning allows to detect and characterize brain tumors as well as metastases. Setting and patients In this case report, we present two cases of newborns antenatally diagnosed with hydrocephalus with no further pathology detected in repeated cranial ultrasound and, in one case, fetal MRI. We performed ULF imaging using a portable 0.064T MRI during natural sleep and high-field 3T MRI to investigate the etiology of congenital hydrocephalus in these infants. Main results ULF imaging revealed a tumor of the fossa cranii posterior in both cases. MRI signalling detected in ULF imaging was specific for each tumor (ATRT, low grade glioma). In one case, ULF imaging also detected intracerebral metastasis. Conclusions We demonstrated that ULF imaging is able to detect tumors of the fossa cranii posterior that are not detected on ultrasound and shows their specific MR-signalling as well as detect metastasis. Additionally, compared to 3T MRI, ULF MRI was able to reveal significant findings while requiring fewer resources and being easier to perform. Therefore, we propose that children with congenital hydrocephalus not showing any abnormalities on cranial ultrasound should undergo ULF MRI. This imaging modality holds potential for monitoring neonatal tumors and detecting metastasis.
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Affiliation(s)
- Anne Groteklaes
- Department of Neonatology and Pediatric Intensive Care, Children’s Hospital, University Hospital Bonn, Bonn, Germany
| | - Till Dresbach
- Department of Neonatology and Pediatric Intensive Care, Children’s Hospital, University Hospital Bonn, Bonn, Germany
| | - Markus Born
- Division of Pediatric Radiology, Department of Radiology, University Hospital Bonn, Bonn, Germany
| | - Andreas Mueller
- Department of Neonatology and Pediatric Intensive Care, Children’s Hospital, University Hospital Bonn, Bonn, Germany
| | - Hemmen Sabir
- Department of Neonatology and Pediatric Intensive Care, Children’s Hospital, University Hospital Bonn, Bonn, Germany
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Okar SV, Kawatra KD, Thommana AA, Vultorius DC, Nair G, Gaitán MI, Norato G, Mina Y, Fletcher A, Reich DS, Cortese I. Portable ultra-low-field MRI for progressive multifocal leukoencephalopathy: Case studies, sensitivity, and potential applications. J Neurol 2025; 272:193. [PMID: 39932567 PMCID: PMC11814002 DOI: 10.1007/s00415-025-12938-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2024] [Revised: 01/10/2025] [Accepted: 01/12/2025] [Indexed: 02/14/2025]
Abstract
BACKGROUND AND OBJECTIVE Progressive multifocal leukoencephalopathy (PML) is a severe, disabling infection caused by JC virus reactivation. PML-related disability complicates the MRI monitoring needed to assess treatment interventions in clinical trial or compassionate use settings. Portable ultra-low-field MRI (pULF-MRI) offers a convenient approach when such frequent imaging is needed. We evaluated the potential utility of pULF-MRI as an adjunctive tool for decreasing the burden of clinical study participation and clinical management in PML. METHODS We examined paired high-field (HF) and pULF-MRI scans from 11 patients, aged 49 ± 15 years. pULF-MRI images with corresponding HF-MRI were coupled to depict key imaging findings of PML, including three patients with longitudinal evaluations, one with bedside pULF-MRI. The images were then independently assessed by two blinded raters, not involved in image acquisition or initial evaluations, who sequentially rated diagnostic accuracy of pULF-MRI scans compared to the HF-MRI. Longitudinal evaluations were performed for three patients, one with bedside pULF-MRI. RESULTS T2-FLAIR lesions were detected with pULF-ULF in all cases when present on HF-MRI. Median sensitivity and specificity were 62% and 100%, respectively. T1WI hypointense areas showed similar performance. Focal volume loss was present in 8/11 HF-MRI scans, with sensitivity and specificity of detection by pULF-MRI of 100% and 94%, respectively. Contrast enhancement was seen in a single case on both pULF- and HF-MRI. Follow-up pULF-MRI showed lesion changes in two cases, and stable findings in one case, consistent with HF-MRI. DISCUSSION pULF-MRI shows promise in evaluation and monitoring of PML, showing moderate-to-high accuracy even when evaluations were unaided by HF-MRI. Our results highlight a potential application of pULF-MRI for facilitating participation in PML clinical research and more generally as a way to reduce burden of clinical management for this disabled patient population.
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Affiliation(s)
- Serhat V Okar
- Translational Neuroradiology Section, National Institute of Neurological Disorders and Stroke, National Institute of Health, Bethesda, MD, USA
| | - Karan D Kawatra
- Neuroimmunology Clinic, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Ashley A Thommana
- Translational Neuroradiology Section, National Institute of Neurological Disorders and Stroke, National Institute of Health, Bethesda, MD, USA
| | - Daniela C Vultorius
- Experimental Immunotherapeutics Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Building 10, Room 5C103, 10 Center Drive, Bethesda, MD, 20814, USA
| | - Govind Nair
- qMRI Core Facility, National Institute of Neurological Disorders and Stroke, National Institute of Health, Bethesda, MD, USA
| | - María I Gaitán
- Translational Neuroradiology Section, National Institute of Neurological Disorders and Stroke, National Institute of Health, Bethesda, MD, USA
| | - Gina Norato
- Office of Biostatistics, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Yair Mina
- Neuroimmunology Clinic, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Anita Fletcher
- Neuroimmunology Clinic, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Daniel S Reich
- Translational Neuroradiology Section, National Institute of Neurological Disorders and Stroke, National Institute of Health, Bethesda, MD, USA
| | - Irene Cortese
- Experimental Immunotherapeutics Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Building 10, Room 5C103, 10 Center Drive, Bethesda, MD, 20814, USA.
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Zabinska J, de Havenon A, Sheth KN. Recent advances in portable, low-field magnetic resonance imaging in cerebrovascular disease. Curr Opin Neurol 2025; 38:35-39. [PMID: 39624032 DOI: 10.1097/wco.0000000000001338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2025]
Abstract
PURPOSE OF REVIEW This review aims to describe recent advances in low-field (0.064 T) magnetic resonance imaging (LF-MRI) of cerebrovascular disease, including ischemic and hemorrhagic stroke and white matter hyperintensities. RECENT FINDINGS Since 2023, several studies have highlighted the rapidly changing landscape of portable, low-field MRI (LF-MRI) and its applications in stroke and cerebrovascular disease. The advantages of using LF-MRI in these settings are multifold: cheaper and dynamic imaging of this patient population confers closer observation during the acute and chronic stages of cerebrovascular disease. Initial deployments of the device span a variety of acute and emergency settings, including imaging around thrombolytic administration, endovascular reperfusion, intracerebral hemorrhage management, and cardiovascular intensive care. LF-MRI also has an important role in cerebrovascular disease monitoring and prevention, namely white matter hyperintensity (WMH) progression and vascular and Alzheimer's dementia. Early studies suggest reliable sensitivity and specificity for these pathologies. With further improvements to LF-MRI hardware, software and postprocessing on the horizon, we anticipate the device's ability to provide inexpensive and flexible neuroimaging to a wide array of healthcare settings that treat, prevent, and manage cerebrovascular disease. SUMMARY Recent studies indicate that LF-MRI promotes rapid, cost-effective, and clinically useful neuroimaging at various clinical timepoints throughout stroke and cerebrovascular disease progression and management.
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Affiliation(s)
- Julia Zabinska
- Department of Neurology, Yale Center for Brain & Mind Health, Yale School of Medicine, New Haven, Connecticut, USA
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Sarty GE, Vidarsson L, Hansen C, Corrigal K, Sutherland L, Jamieson M, Hogue M, Kassahun H, Greyeyes W, Teixeira D, Goertzen L, McEvoy J, Pollard M. Learning to build low-field MRIs for remote northern communities. FRONTIERS IN NEUROIMAGING 2025; 3:1521517. [PMID: 39898014 PMCID: PMC11782269 DOI: 10.3389/fnimg.2024.1521517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2024] [Accepted: 12/24/2024] [Indexed: 02/04/2025]
Abstract
Low-field Magnetic Resonance Imaging (MRI) has the potential to provide autonomous accessible neuroimaging in remote communities, particularly in the Canadian north. Remoteness necessitates that these MRIs be built and maintained within the communities. This approach not only ensures that the MRIs remain operational but will also allow the youth from the communities to pursue technical careers at home. The first step in this vision is to establish that the technical resources needed for building MRIs are available in remote communities and to establish an educational program that will give students the required technical skills. Over the summer of 2024, a team of students working within an Aircraft Maintenance Engineering (AME) program built the hardware for a wrist-sized prototype MRI. The student team included a high school student, AME students, engineering students and a post doctoral fellow. The skills required to maintain aircraft, namely 3D printing, sheet metal work and electrical harness building, were sufficient to build a low-field MRI. The prototype built was a radio frequency (RF) encoding MRI, whose design was optimized for eventual use in space, but the techniques and procedures developed are applicable to other MRI designs. Furthermore the breadth of students from high school to the post doctoral fellow level facilitated an extremely rich learning environment for the students while they focused on the task of designing and building the prototype MRI. Educational programs around building low-field MRIs can be created at all levels.
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Affiliation(s)
- Gordon E. Sarty
- Space MRI Lab, quanTA Centre, University of Saskatchewan, Saskatoon, SK, Canada
| | | | - Christopher Hansen
- Space MRI Lab, quanTA Centre, University of Saskatchewan, Saskatoon, SK, Canada
- Aircraft Maintenance Engineering Program, Saskatchewan Indian Institute of Technology, Saskatoon, SK, Canada
| | - Keifer Corrigal
- Aircraft Maintenance Engineering Program, Saskatchewan Indian Institute of Technology, Saskatoon, SK, Canada
| | - Lionel Sutherland
- Aircraft Maintenance Engineering Program, Saskatchewan Indian Institute of Technology, Saskatoon, SK, Canada
| | - Millie Jamieson
- Space MRI Lab, quanTA Centre, University of Saskatchewan, Saskatoon, SK, Canada
| | - Micheal Hogue
- Space MRI Lab, quanTA Centre, University of Saskatchewan, Saskatoon, SK, Canada
| | - Haile Kassahun
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - William Greyeyes
- Aircraft Maintenance Engineering Program, Saskatchewan Indian Institute of Technology, Saskatoon, SK, Canada
| | - David Teixeira
- Aircraft Maintenance Engineering Program, Saskatchewan Indian Institute of Technology, Saskatoon, SK, Canada
| | - Lawrence Goertzen
- Aircraft Maintenance Engineering Program, Saskatchewan Indian Institute of Technology, Saskatoon, SK, Canada
| | - Jonathan McEvoy
- Aircraft Maintenance Engineering Program, Saskatchewan Indian Institute of Technology, Saskatoon, SK, Canada
| | - Mark Pollard
- Aircraft Maintenance Engineering Program, Saskatchewan Indian Institute of Technology, Saskatoon, SK, Canada
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Okar SV, Nair G, Kawatra KD, Thommana AA, Donnay CA, Gaitán MI, Stein JM, Reich DS. High-Field-Blinded Assessment of Portable Ultra-Low-Field Brain MRI for Multiple Sclerosis. J Neuroimaging 2025; 35:e70005. [PMID: 39815369 PMCID: PMC11735652 DOI: 10.1111/jon.70005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2024] [Revised: 12/17/2024] [Accepted: 12/23/2024] [Indexed: 01/18/2025] Open
Abstract
BACKGROUND AND PURPOSE MRI is crucial for multiple sclerosis (MS), but the relative value of portable ultra-low field MRI (pULF-MRI), a technology that holds promise for extending access to MRI, is unknown. We assessed white matter lesion (WML) detection on pULF-MRI compared to high-field MRI (HF-MRI), focusing on blinded assessments, assessor self-training, and multiplanar acquisitions. METHODS Fifty-five adults with MS underwent pULF-MRI following their HF-MRI. Two neuroradiologists independently assessed pULF-MRI images in an evaluation process, including initial assessment blinded to HF-MRI, self-training with reference to HF-MRI and evaluation of 20 cases with additional T2-fluid-attenuated inversion recovery in an additional plane. A third rater conducted cross-referenced analysis with HF-MRI data to determine true-positive lesions, false-positive areas, and case-level sensitivity and positive predictive value. RESULTS The mean age of participants was 50 years (standard deviation: 11; 74% women). Initially, Rater 2 marked more false-positive areas than Rater 1 (p = 0.003). After self-training, both raters embraced a conservative approach, with Rater 2 marking fewer false-positive areas (p = 0.01). Both raters maintained 100% case-level sensitivity and positive predictive value for detecting at least one WML, particularly in periventricular areas. Multiplanar acquisitions reduced both false-positive areas and true-positive lesions. True-positive lesions and false-positive areas had similar contrast-to-noise ratios in the juxtacortical region (p = 0.73) but not in periventricular, deep parenchymal regions (p = 0.004, p = 0.01). CONCLUSION With adequate training, radiological interpretation of pULF-MRI has high sensitivity and positive predictive value for MS lesions but should be approached conservatively. These results suggest utility for patient triage, potentially reducing diagnostic delay, and screening high-risk individuals.
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Affiliation(s)
- Serhat V. Okar
- Translational Neuroradiology Section, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMarylandUSA
| | - Govind Nair
- qMRI Core FacilityNational Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMarylandUSA
| | - Karan D. Kawatra
- Neuroimmunology Clinic, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMarylandUSA
| | - Ashley A. Thommana
- Translational Neuroradiology Section, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMarylandUSA
| | - Corinne A. Donnay
- Translational Neuroradiology Section, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMarylandUSA
| | - María I. Gaitán
- Translational Neuroradiology Section, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMarylandUSA
| | - Joel M. Stein
- Center for Neuroengineering and TherapeuticsUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
- Department of RadiologyPerelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Daniel S. Reich
- Translational Neuroradiology Section, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMarylandUSA
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12
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Cho SM, Khanduja S, Wilcox C, Dinh K, Kim J, Kang JK, Chinedozi ID, Darby Z, Acton M, Rando H, Briscoe J, Bush EL, Sair HI, Pitts J, Arlinghaus LR, Wandji ACN, Moreno E, Torres G, Akkanti B, Gavito-Higuera J, Keller S, Choi HA, Kim BS, Gusdon A, Whitman GJ. Clinical Use of Bedside Portable Ultra-Low-Field Brain Magnetic Resonance Imaging in Patients on Extracorporeal Membrane Oxygenation: Results From the Multicenter SAFE MRI ECMO Study. Circulation 2024; 150:1955-1965. [PMID: 39342513 PMCID: PMC11627327 DOI: 10.1161/circulationaha.124.069187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Accepted: 09/03/2024] [Indexed: 10/01/2024]
Abstract
BACKGROUND Early detection of acute brain injury (ABI) at the bedside is critical in improving survival for patients with extracorporeal membrane oxygenation (ECMO) support. We aimed to examine the safety of ultra-low-field (ULF; 0.064-T) portable magnetic resonance imaging (pMRI) in patients undergoing ECMO and to investigate the ABI frequency and types with ULF-pMRI. METHODS This was a multicenter prospective observational study (SAFE MRI ECMO study [Assessing the Safety and Feasibility of Bedside Portable Low-Field Brain Magnetic Resonance Imaging in Patients on ECMO]; NCT05469139) from 2 tertiary centers (Johns Hopkins, Baltimore, MD and University of Texas-Houston) with specially trained intensive care units. Primary outcomes were safety of ULF-pMRI during ECMO support, defined as completion of ULF-pMRI without significant adverse events. RESULTS Of 53 eligible patients, 3 were not scanned because of a large head size that did not fit within the head coil. ULF-pMRI was performed in 50 patients (median age, 58 years; 52% male), with 34 patients (68%) on venoarterial ECMO and 16 patients (32%) on venovenous ECMO. Of 34 patients on venoarterial ECMO, 11 (22%) were centrally cannulated and 23 (46%) were peripherally cannulated. In venovenous ECMO, 9 (18%) had single-lumen cannulation and 7 (14%) had double-lumen cannulation. Of 50 patients, adverse events occurred in 3 patients (6%), with 2 minor adverse events (ECMO suction event; transient low ECMO flow) and one serious adverse event (intra-aortic balloon pump malfunction attributable to electrocardiographic artifacts). All images demonstrated discernible intracranial pathologies with good quality. ABI was observed in 22 patients (44%). Ischemic stroke (36%) was the most common type of ABI, followed by intracranial hemorrhage (6%) and hypoxic-ischemic brain injury (4%). Of 18 patients (36%) with both ULF-pMRI and head computed tomography within 24 hours, ABI was observed in 9 patients with a total of 10 events (8 ischemic, 2 hemorrhagic events). Of the 8 ischemic events, pMRI observed all 8, and head computed tomography observed only 4 events. For intracranial hemorrhage, pMRI observed only 1 of them, and head computed tomography observed both (2 events). CONCLUSIONS Our study demonstrates that ULF-pMRI can be performed in patients on ECMO across different ECMO cannulation strategies in specially trained intensive care units. The incidence of ABI was high, seen in 44% of ULF-pMRI studies. ULF-pMRI imaging appears to be more sensitive to ABI, particularly ischemic stroke, compared with head computed tomography.
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Affiliation(s)
- Sung-Min Cho
- Department of Surgery, Division of Cardiac Surgery (S.-M.C., S.K., C.W., J.K.K., I.D.C., Z.D., M.A., H.R., J.B., S.K., B.S.K., G.J.W.), Johns Hopkins University School of Medicine, Baltimore, MD
- Departments of Neurology, Neurosurgery, and Anesthesiology and Critical Care Medicine, Neuroscience Critical Care Division (S.-M.C., J.K.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Shivalika Khanduja
- Department of Surgery, Division of Cardiac Surgery (S.-M.C., S.K., C.W., J.K.K., I.D.C., Z.D., M.A., H.R., J.B., S.K., B.S.K., G.J.W.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Christopher Wilcox
- Department of Surgery, Division of Cardiac Surgery (S.-M.C., S.K., C.W., J.K.K., I.D.C., Z.D., M.A., H.R., J.B., S.K., B.S.K., G.J.W.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Kha Dinh
- Divisions of Pulmonary, Critical Care, and Sleep Medicine (K.D., B.A.), University of Texas Health Science Center at Houston
| | - Jiah Kim
- Departments of Neurology, Neurosurgery, and Anesthesiology and Critical Care Medicine, Neuroscience Critical Care Division (S.-M.C., J.K.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Jin Kook Kang
- Department of Surgery, Division of Cardiac Surgery (S.-M.C., S.K., C.W., J.K.K., I.D.C., Z.D., M.A., H.R., J.B., S.K., B.S.K., G.J.W.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Ifeanyi David Chinedozi
- Department of Surgery, Division of Cardiac Surgery (S.-M.C., S.K., C.W., J.K.K., I.D.C., Z.D., M.A., H.R., J.B., S.K., B.S.K., G.J.W.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Zachary Darby
- Department of Surgery, Division of Cardiac Surgery (S.-M.C., S.K., C.W., J.K.K., I.D.C., Z.D., M.A., H.R., J.B., S.K., B.S.K., G.J.W.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Matthew Acton
- Department of Surgery, Division of Cardiac Surgery (S.-M.C., S.K., C.W., J.K.K., I.D.C., Z.D., M.A., H.R., J.B., S.K., B.S.K., G.J.W.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Hannah Rando
- Department of Surgery, Division of Cardiac Surgery (S.-M.C., S.K., C.W., J.K.K., I.D.C., Z.D., M.A., H.R., J.B., S.K., B.S.K., G.J.W.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Jessica Briscoe
- Department of Surgery, Division of Cardiac Surgery (S.-M.C., S.K., C.W., J.K.K., I.D.C., Z.D., M.A., H.R., J.B., S.K., B.S.K., G.J.W.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Errol L. Bush
- Department of Surgery, Division of Thoracic Surgery (E.L.B.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Haris I. Sair
- Department of Radiology and Radiological Science, Division of Neuroradiology (H.I.S.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - John Pitts
- Hyperfine, Inc, Guilford, CT (J.P., L.R.A.)
| | | | - Audrey-Carelle N. Wandji
- Department of Neurosurgery, Division of Neurocritical Care, McGovern School of Medicine (A.-C.N.W., E.M., G.T., J.G.-H., H.A.C., A.G.), University of Texas Health Science Center at Houston
| | - Elena Moreno
- Department of Neurosurgery, Division of Neurocritical Care, McGovern School of Medicine (A.-C.N.W., E.M., G.T., J.G.-H., H.A.C., A.G.), University of Texas Health Science Center at Houston
| | - Glenda Torres
- Department of Neurosurgery, Division of Neurocritical Care, McGovern School of Medicine (A.-C.N.W., E.M., G.T., J.G.-H., H.A.C., A.G.), University of Texas Health Science Center at Houston
| | - Bindu Akkanti
- Divisions of Pulmonary, Critical Care, and Sleep Medicine (K.D., B.A.), University of Texas Health Science Center at Houston
| | - Jose Gavito-Higuera
- Department of Neurosurgery, Division of Neurocritical Care, McGovern School of Medicine (A.-C.N.W., E.M., G.T., J.G.-H., H.A.C., A.G.), University of Texas Health Science Center at Houston
| | - Steven Keller
- Department of Surgery, Division of Cardiac Surgery (S.-M.C., S.K., C.W., J.K.K., I.D.C., Z.D., M.A., H.R., J.B., S.K., B.S.K., G.J.W.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - HuiMahn A. Choi
- Department of Neurosurgery, Division of Neurocritical Care, McGovern School of Medicine (A.-C.N.W., E.M., G.T., J.G.-H., H.A.C., A.G.), University of Texas Health Science Center at Houston
| | - Bo Soo Kim
- Department of Surgery, Division of Cardiac Surgery (S.-M.C., S.K., C.W., J.K.K., I.D.C., Z.D., M.A., H.R., J.B., S.K., B.S.K., G.J.W.), Johns Hopkins University School of Medicine, Baltimore, MD
| | - Aaron Gusdon
- Department of Neurosurgery, Division of Neurocritical Care, McGovern School of Medicine (A.-C.N.W., E.M., G.T., J.G.-H., H.A.C., A.G.), University of Texas Health Science Center at Houston
| | - Glenn J. Whitman
- Department of Surgery, Division of Cardiac Surgery (S.-M.C., S.K., C.W., J.K.K., I.D.C., Z.D., M.A., H.R., J.B., S.K., B.S.K., G.J.W.), Johns Hopkins University School of Medicine, Baltimore, MD
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13
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Sorby-Adams AJ, Guo J, Laso P, Kirsch JE, Zabinska J, Garcia Guarniz AL, Schaefer PW, Payabvash S, de Havenon A, Rosen MS, Sheth KN, Gomez-Isla T, Iglesias JE, Kimberly WT. Portable, low-field magnetic resonance imaging for evaluation of Alzheimer's disease. Nat Commun 2024; 15:10488. [PMID: 39622805 PMCID: PMC11612292 DOI: 10.1038/s41467-024-54972-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2024] [Accepted: 11/21/2024] [Indexed: 12/06/2024] Open
Abstract
Portable, low-field magnetic resonance imaging (LF-MRI) of the brain may facilitate point-of-care assessment of patients with Alzheimer's disease (AD) in settings where conventional MRI cannot. However, image quality is limited by a lower signal-to-noise ratio. Here, we optimize LF-MRI acquisition and develop a freely available machine learning pipeline to quantify brain morphometry and white matter hyperintensities (WMH). We validate the pipeline and apply it to outpatients presenting with mild cognitive impairment or dementia due to AD. We find hippocampal volumes from ≤ 3 mm isotropic LF-MRI scans have agreement with conventional MRI and are more accurate than anisotropic counterparts. We also show WMH volume has agreement between manual segmentation and the automated pipeline. The increased availability and reduced cost of LF-MRI, in combination with our machine learning pipeline, has the potential to increase access to neuroimaging for dementia.
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Affiliation(s)
- Annabel J Sorby-Adams
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Jennifer Guo
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Pablo Laso
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - John E Kirsch
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Julia Zabinska
- Department of Neurology, Center for Brain & Mind Health, Yale New Haven Hospital and Yale School of Medicine, New Haven, CT, USA
| | - Ana-Lucia Garcia Guarniz
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Pamela W Schaefer
- Division of Neuroradiology, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Seyedmehdi Payabvash
- Division of Neuroradiology, Department of Radiology and Biomedical Imaging, Yale New Haven Hospital and Yale University School of Medicine, New Haven, CT, USA
| | - Adam de Havenon
- Department of Neurology, Center for Brain & Mind Health, Yale New Haven Hospital and Yale School of Medicine, New Haven, CT, USA
| | - Matthew S Rosen
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Kevin N Sheth
- Department of Neurology, Center for Brain & Mind Health, Yale New Haven Hospital and Yale School of Medicine, New Haven, CT, USA
| | - Teresa Gomez-Isla
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - J Eugenio Iglesias
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - W Taylor Kimberly
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA.
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14
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Su S, Zhao Y, Ding Y, Lau V, Xiao L, Leung GKK, Lau GKK, Huang F, Vardhanabhuti V, Leong ATL, Wu EX. Ultra-low-field magnetization transfer imaging at 0.055T with low specific absorption rate. Magn Reson Med 2024; 92:2420-2432. [PMID: 39044654 DOI: 10.1002/mrm.30231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 06/14/2024] [Accepted: 07/09/2024] [Indexed: 07/25/2024]
Abstract
PURPOSE To demonstrate magnetization transfer (MT) effects with low specific absorption rate (SAR) on ultra-low-field (ULF) MRI. METHODS MT imaging was implemented by using sinc-modulated RF pulse train (SPT) modules to provide bilateral off-resonance irradiation. They were incorporated into 3D gradient echo (GRE) and fast spin echo (FSE) protocols on a shielding-free 0.055T head scanner. MT effects were first verified using phantoms. Brain MT imaging was conducted in both healthy subjects and patients. RESULTS MT effects were clearly observed in phantoms using six SPT modules with total flip angle 3600° at central primary saturation bands of approximate offset ±786 Hz, even in the presence of large relative B0 inhomogeneity. For brain, strong MT effects were observed in gray matter, white matter, and muscle in 3D GRE and FSE imaging using six and sixteen SPT modules with total flip angle 3600° and 9600°, respectively. Fat, cerebrospinal fluid, and blood exhibited relatively weak MT effects. MT preparation enhanced tissue contrasts in T2-weighted and FLAIR-like images, and improved brain lesion delineation. The estimated MT SAR was 0.0024 and 0.0008 W/kg for two protocols, respectively, which is far below the US Food and Drug Administration (FDA) limit of 3.0 W/kg. CONCLUSION Robust MT effects can be readily obtained at ULF with extremely low SAR, despite poor relative B0 homogeneity in ppm. This unique advantage enables flexible MT pulse design and implementation on low-cost ULF MRI platforms to achieve strong MT effects in brain and beyond, potentially augmenting their clinical utility in the future.
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Affiliation(s)
- Shi Su
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, China
| | - Yujiao Zhao
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, China
| | - Ye Ding
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, China
| | - Vick Lau
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, China
| | - Linfang Xiao
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, China
| | - Gilberto K K Leung
- Department of Surgery, The University of Hong Kong, Hong Kong SAR, China
| | - Gary K K Lau
- Department of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Fan Huang
- Department of Diagnostic Radiology, The University of Hong Kong, Hong Kong SAR, China
| | - Vince Vardhanabhuti
- Department of Diagnostic Radiology, The University of Hong Kong, Hong Kong SAR, China
| | - Alex T L Leong
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, China
| | - Ed X Wu
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, China
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15
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Lim TR, Suthiphosuwan S, Micieli J, Vosoughi R, Schneider R, Lin AW, Chen YA, Muccilli A, Marriott JJ, Selchen D, Mathur S, Oh J, Bharatha A. Low-Field (64 mT) Portable MRI for Rapid Point-of-Care Diagnosis of Dissemination in Space in Patients Presenting with Optic Neuritis. AJNR Am J Neuroradiol 2024; 45:1819-1825. [PMID: 38926091 PMCID: PMC11543069 DOI: 10.3174/ajnr.a8395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Accepted: 06/22/2024] [Indexed: 06/28/2024]
Abstract
BACKGROUND AND PURPOSE Low-field 64 mT portable brain MRI has recently shown diagnostic promise for MS. This study aimed to evaluate the utility of portable MRI (pMRI) in assessing dissemination in space (DIS) in patients presenting with optic neuritis and determine whether deploying pMRI in the MS clinic can shorten the time from symptom onset to MRI. MATERIALS AND METHODS Newly diagnosed patients with optic neuritis referred to a tertiary academic MS center from July 2022 to January 2024 underwent both point-of-care pMRI and subsequent 3T conventional MRI (cMRI). Images were evaluated for periventricular (PV), juxtacortical (JC), and infratentorial (IT) lesions. DIS was determined on brain MRI per 2017 McDonald criteria. Test characteristics were computed by using cMRI as the reference. Interrater and intermodality agreement between pMRI and cMRI were evaluated by using the Cohen κ. Time from symptom onset to pMRI and cMRI during the study period was compared with the preceding 1.5 years before pMRI implementation by using Kruskal-Wallis with post hoc Dunn tests. RESULTS Twenty patients (median age: 32.5 years [interquartile range {IQR}, 28-40]; 80% women) were included, of whom 9 (45%) and 5 (25%) had DIS on cMRI and pMRI, respectively. Median time interval between pMRI and cMRI was 7 days (IQR, 3.5-12.5). Interrater agreement was very good for PV (95%, κ = 0.89), and good for JC and IT lesions (90%, κ = 0.69 for both). Intermodality agreement was good for PV (90%, κ = 0.80) and JC (85%, κ = 0.63), and moderate for IT lesions (75%, κ = 0.42) and DIS (80%, κ = 0.58). pMRI had a sensitivity of 56% and specificity of 100% for DIS. The median time from symptom onset to pMRI was significantly shorter (8.5 days [IQR 7-12]) compared with the interval to cMRI before pMRI deployment (21 days [IQR 8-49], n = 50) and after pMRI deployment (15 days [IQR 12-29], n = 30) (both P < .01). Time from symptom onset to cMRI in those periods was not significantly different (P = .29). CONCLUSIONS In patients with optic neuritis, pMRI exhibited moderate concordance, moderate sensitivity, and high specificity for DIS compared with cMRI. Its integration into the MS clinic reduced the time from symptom onset to MRI. Further studies are warranted to evaluate the role of pMRI in expediting early MS diagnosis and as an imaging tool in resource-limited settings.
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Affiliation(s)
- Timothy Reynold Lim
- From the Division of Neuroradiology, Department of Medical Imaging (T.R.L., S.S., A.W.L., Y.A.C., S.M. A.B.), St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Suradech Suthiphosuwan
- From the Division of Neuroradiology, Department of Medical Imaging (T.R.L., S.S., A.W.L., Y.A.C., S.M. A.B.), St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Jonathan Micieli
- Department of Ophthalmology and Vision Sciences (J.M.), University of Toronto, Toronto, Ontario, Canada
- Kensington Vision and Research Center (J.M.), Toronto, Ontario, Canada
- Department of Ophthalmology (J.M.), St. Michael's Hospital, Unity Health, Toronto, Ontario, Canada
| | - Reza Vosoughi
- Division of Neurology, Department of Medicine (R.V., R.S., A.M., J.J.M., D.S., J.O.), St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Raphael Schneider
- Division of Neurology, Department of Medicine (R.V., R.S., A.M., J.J.M., D.S., J.O.), St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
- Li Ka Shing Knowledge Institute and Keenan Research Centre for Biomedical Science (R.S. D.S., S.M.), Toronto, Ontario, Canada
| | - Amy W Lin
- From the Division of Neuroradiology, Department of Medical Imaging (T.R.L., S.S., A.W.L., Y.A.C., S.M. A.B.), St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Yingming Amy Chen
- From the Division of Neuroradiology, Department of Medical Imaging (T.R.L., S.S., A.W.L., Y.A.C., S.M. A.B.), St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Alexandra Muccilli
- Division of Neurology, Department of Medicine (R.V., R.S., A.M., J.J.M., D.S., J.O.), St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - James J Marriott
- Division of Neurology, Department of Medicine (R.V., R.S., A.M., J.J.M., D.S., J.O.), St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Daniel Selchen
- Division of Neurology, Department of Medicine (R.V., R.S., A.M., J.J.M., D.S., J.O.), St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
- Li Ka Shing Knowledge Institute and Keenan Research Centre for Biomedical Science (R.S. D.S., S.M.), Toronto, Ontario, Canada
| | - Shobhit Mathur
- From the Division of Neuroradiology, Department of Medical Imaging (T.R.L., S.S., A.W.L., Y.A.C., S.M. A.B.), St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
- Li Ka Shing Knowledge Institute and Keenan Research Centre for Biomedical Science (R.S. D.S., S.M.), Toronto, Ontario, Canada
| | - Jiwon Oh
- Division of Neurology, Department of Medicine (R.V., R.S., A.M., J.J.M., D.S., J.O.), St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
- Department of Neurology (J.O.), Johns Hopkins University, Baltimore, Maryland
| | - Aditya Bharatha
- From the Division of Neuroradiology, Department of Medical Imaging (T.R.L., S.S., A.W.L., Y.A.C., S.M. A.B.), St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
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16
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Su S, Hu J, Ding Y, Zhang J, Lau V, Zhao Y, Wu EX. Ultra-low-field magnetic resonance angiography at 0.05 T: A preliminary study. NMR IN BIOMEDICINE 2024; 37:e5213. [PMID: 39032076 DOI: 10.1002/nbm.5213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Revised: 05/24/2024] [Accepted: 06/18/2024] [Indexed: 07/22/2024]
Abstract
We aim to explore the feasibility of head and neck time-of-flight (TOF) magnetic resonance angiography (MRA) at ultra-low-field (ULF). TOF MRA was conducted on a highly simplified 0.05 T MRI scanner with no radiofrequency (RF) and magnetic shielding. A flow-compensated three-dimensional (3D) gradient echo (GRE) sequence with a tilt-optimized nonsaturated excitation RF pulse, and a flow-compensated multislice two-dimensional (2D) GRE sequence, were implemented for cerebral artery and vein imaging, respectively. For carotid artery and jugular vein imaging, flow-compensated 2D GRE sequences were utilized with venous and arterial blood presaturation, respectively. MRA was performed on young healthy subjects. Vessel-to-background contrast was experimentally observed with strong blood inflow effect and background tissue suppression. The large primary cerebral arteries and veins, carotid arteries, jugular veins, and artery bifurcations could be identified in both raw GRE images and maximum intensity projections. The primary brain and neck arteries were found to be reproducible among multiple examination sessions. These preliminary experimental results demonstrated the possibility of artery TOF MRA on low-cost 0.05 T scanners for the first time, despite the extremely low MR signal. We expect to improve the quality of ULF TOF MRA in the near future through sequence development and optimization, ongoing advances in ULF hardware and image formation, and the use of vascular T1 contrast agents.
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Affiliation(s)
- Shi Su
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, People's Republic of China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, People's Republic of China
| | - Jiahao Hu
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, People's Republic of China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, People's Republic of China
| | - Ye Ding
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, People's Republic of China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, People's Republic of China
| | - Junhao Zhang
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, People's Republic of China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, People's Republic of China
| | - Vick Lau
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, People's Republic of China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, People's Republic of China
| | - Yujiao Zhao
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, People's Republic of China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, People's Republic of China
| | - Ed X Wu
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, People's Republic of China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, People's Republic of China
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Ariyasingha NM, Samoilenko A, Chowdhury MRH, Nantogma S, Oladun C, Birchall JR, Bawardi T, Salnikov OG, Kovtunova LM, Bukhtiyarov VI, Shi Z, Luo K, Tan S, Koptyug IV, Goodson BM, Chekmenev EY. Developing Hyperpolarized Butane Gas for Ventilation Lung Imaging. CHEMICAL & BIOMEDICAL IMAGING 2024; 2:698-710. [PMID: 39483636 PMCID: PMC11523004 DOI: 10.1021/cbmi.4c00041] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2024] [Revised: 07/03/2024] [Accepted: 07/05/2024] [Indexed: 11/03/2024]
Abstract
NMR hyperpolarization dramatically improves the detection sensitivity of magnetic resonance through the increase in nuclear spin polarization. Because of the sensitivity increase by several orders of magnitude, additional applications have been unlocked, including imaging of gases in physiologically relevant conditions. Hyperpolarized 129Xe gas recently received FDA approval as the first inhalable gaseous MRI contrast agent for clinical functional lung imaging of a wide range of pulmonary diseases. However, production and utilization of hyperpolarized 129Xe gas faces a number of translational challenges including the high cost and complexity of contrast agent production and imaging using proton-only (i.e., conventional) clinical MRI scanners, which are typically not suited to scan 129Xe nuclei. As a solution to circumvent the translational challenges of hyperpolarized 129Xe, we have recently demonstrated the feasibility of a simple and cheap process for production of proton-hyperpolarized propane gas contrast agent using ultralow-cost disposable production equipment and demonstrated the feasibility of lung ventilation imaging using hyperpolarized propane gas in excised pig lungs. However, previous pilot studies have concluded that the hyperpolarized state of propane gas decays very fast with an exponential decay T 1 constant of ∼0.8 s at 1 bar (physiologically relevant pressure); moreover, the previously reported production rates were too slow for potential clinical utilization. Here, we investigate the feasibility of high-capacity production of hyperpolarized butane gas via heterogeneous parahydrogen-induced polarization using Rh nanoparticle-based catalyst utilizing butene gas as a precursor for parahydrogen pairwise addition. We demonstrate a remarkable result: the lifetime of the hyperpolarized state can be nearly doubled compared to that of propane (T 1 of ∼1.6 s and long-lived spin-state T S of ∼3.8 s at clinically relevant 1 bar pressure). Moreover, we demonstrate a production speed of up to 0.7 standard liters of hyperpolarized gas per second. These two synergistic developments pave the way to biomedical utilization of proton-hyperpolarized gas media for ventilation imaging. Indeed, here we demonstrate the feasibility of phantom imaging of hyperpolarized butane gas in Tedlar bags and also the feasibility of subsecond 2D ventilation gas imaging in excised rabbit lungs with 1.6 × 1.6 mm2 in-plane resolution using a clinical MRI scanner. The demonstrated results have the potential to revolutionize functional pulmonary imaging with a simple and inexpensive on-demand production of proton-hyperpolarized gas contrast media, followed by visualization on virtually any MRI scanner, including emerging bedside low-field MRI scanner technology.
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Affiliation(s)
- Nuwandi M. Ariyasingha
- Department
of Chemistry, Karmanos Cancer Institute (KCI), Integrative Biosciences
(Ibio), Wayne State University, Detroit, Michigan 48202, United States
| | - Anna Samoilenko
- Department
of Chemistry, Karmanos Cancer Institute (KCI), Integrative Biosciences
(Ibio), Wayne State University, Detroit, Michigan 48202, United States
| | - Md Raduanul H. Chowdhury
- Department
of Chemistry, Karmanos Cancer Institute (KCI), Integrative Biosciences
(Ibio), Wayne State University, Detroit, Michigan 48202, United States
| | - Shiraz Nantogma
- Department
of Chemistry, Karmanos Cancer Institute (KCI), Integrative Biosciences
(Ibio), Wayne State University, Detroit, Michigan 48202, United States
| | - Clementinah Oladun
- Department
of Chemistry, Karmanos Cancer Institute (KCI), Integrative Biosciences
(Ibio), Wayne State University, Detroit, Michigan 48202, United States
| | - Jonathan R. Birchall
- Department
of Chemistry, Karmanos Cancer Institute (KCI), Integrative Biosciences
(Ibio), Wayne State University, Detroit, Michigan 48202, United States
| | - Tarek Bawardi
- Department
of Chemistry, Karmanos Cancer Institute (KCI), Integrative Biosciences
(Ibio), Wayne State University, Detroit, Michigan 48202, United States
| | - Oleg G. Salnikov
- International
Tomography Center SB RAS, 3A Institutskaya St., Novosibirsk 630090, Russia
| | - Larisa M. Kovtunova
- International
Tomography Center SB RAS, 3A Institutskaya St., Novosibirsk 630090, Russia
- Boreskov
Institute of Catalysis SB RAS, 5 Acad, Lavrentiev Pr., Novosibirsk 630090, Russia
| | - Valerii I. Bukhtiyarov
- Boreskov
Institute of Catalysis SB RAS, 5 Acad, Lavrentiev Pr., Novosibirsk 630090, Russia
| | - Zhongjie Shi
- Department
of Pediatrics, Wayne State University, Detroit, Michigan 48202, United States
| | - Kehuan Luo
- Department
of Pediatrics, Wayne State University, Detroit, Michigan 48202, United States
| | - Sidhartha Tan
- Department
of Pediatrics, Wayne State University, Detroit, Michigan 48202, United States
| | - Igor V. Koptyug
- International
Tomography Center SB RAS, 3A Institutskaya St., Novosibirsk 630090, Russia
| | - Boyd M. Goodson
- School
of Chemical & Biomolecular Sciences, Materials Technology Center, Southern Illinois University, Carbondale, Illinois 62901, United States
| | - Eduard Y. Chekmenev
- Department
of Chemistry, Karmanos Cancer Institute (KCI), Integrative Biosciences
(Ibio), Wayne State University, Detroit, Michigan 48202, United States
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Tapp A, Zhao C, Roth HR, Tanedo J, Anwar SM, Bourke NJ, Hajnal J, Nankabirwa V, Deoni S, Lepore N, Linguraru MG. Super-Field MRI Synthesis for Infant Brains Enhanced by Dual Channel Latent Diffusion. MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION : MICCAI ... INTERNATIONAL CONFERENCE ON MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION 2024; 15003:444-454. [PMID: 40297805 PMCID: PMC12033166 DOI: 10.1007/978-3-031-72384-1_42] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/30/2025]
Abstract
In resource-limited settings, portable ultra-low-field (uLF, i.e., 0.064T) magnetic resonance imaging (MRI) systems expand accessibility of radiological scanning, particularly for low-income areas as well as underserved populations like neonates and infants. However, compared to high-field (HF, e.g., ≥ 1.5T) systems, inferior image quality in uLF scanning poses challenges for research and clinical use. To address this, we introduce Super-Field Network (SFNet), a custom swinUNETRv2 with generative adversarial network components that uses uLF MRIs to generate super-field (SF) images comparable to HF MRIs. We acquired a cohort of infant data (n=30, aged 0-2 years) with paired uLF-HF MRI data from a resource-limited setting with an underrepresented population in research. To enhance the small dataset, we present a novel use of latent diffusion to create dual-channel (uLF-HF) paired MRIs. We compare SFNet with state-of-the-art synthesis methods by HF-SF image similarity perceptual scores and by automated HF and SF segmentations of white matter (WM), gray matter (GM), and cerebrospinal fluid (CSF). The best performance was achieved by SFNet trained on the latent diffusion enhanced dataset yielding state-of-the-art results in Fréchet inception distance at 9.08 ± 1.21, perceptual similarity at 0.11 ± 0.01, and PSNR at 22.64 ± 1.31. True HF and SF segmentations had a strong overlap with Dice similarity coefficients of 0.71 ± 0.1, 0.79 ± 0.2, and 0.73 ± 0.08 for WM, GM, and CSF, respectively, in the developing infant brain with incomplete myelination, and displayed 166%, 107%, and 106% improvement over respective uLF-based segmentation metrics. SF MRI supports health equity by enhancing the clinical use of uLF imaging systems and improving the diagnostic capabilities of low-cost portable MRI systems in resource-limited settings and for underserved populations. Our code is made openly available at https://github.com/AustinTapp/SFnet.
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Affiliation(s)
- Austin Tapp
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, DC 20010
| | - Can Zhao
- NVIDIA Corporation, 2788 San Tomas Expressway Santa Clara, CA 95051, USA
| | - Holger R Roth
- NVIDIA Corporation, 2788 San Tomas Expressway Santa Clara, CA 95051, USA
| | - Jeffrey Tanedo
- CIBORG Lab, Department of Radiology, Children's Hospital Los Angeles and University of Southern California, Los Angeles, CA 90027, USA
| | - Syed Muhammad Anwar
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, DC 20010
- School of Medicine and Health Sciences, George Washington University, Washington, DC 20052, USA
| | - Niall J Bourke
- Centre for Neuroimaging Sciences, King's College London, United Kingdom
| | - Joseph Hajnal
- Centre for the Developing Brain, School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | | | - Sean Deoni
- Bill and Melinda Gates Foundation, PO Box 23350, Seattle, WA, 98102, USA
| | - Natasha Lepore
- CIBORG Lab, Department of Radiology, Children's Hospital Los Angeles and University of Southern California, Los Angeles, CA 90027, USA
| | - Marius George Linguraru
- Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Hospital, Washington, DC 20010
- School of Medicine and Health Sciences, George Washington University, Washington, DC 20052, USA
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Tu LH, Tegtmeyer K, de Oliveira Santo ID, Venkatesh AK, Forman HP, Mahajan A, Melnick ER. Abbreviated MRI in the evaluation of dizziness: report turnaround times and impact on length of stay compared to CT, CTA, and conventional MRI. Emerg Radiol 2024; 31:705-711. [PMID: 39034381 DOI: 10.1007/s10140-024-02273-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2024] [Accepted: 07/16/2024] [Indexed: 07/23/2024]
Abstract
PURPOSE Neuroimaging is often used in the emergency department (ED) to evaluate for posterior circulation strokes in patients with dizziness, commonly with CT/CTA due to speed and availability. Although MRI offers more sensitive evaluation, it is less commonly used, in part due to slower turnaround times. We assess the potential for abbreviated MRI to improve reporting times and impact on length of stay (LOS) compared to conventional MRI (as well as CT/CTA) in the evaluation of acute dizziness. MATERIALS AND METHODS We performed a retrospective analysis of length of stay via LASSO regression for patients presenting to the ED with dizziness and discharged directly from the ED over 4 years (1/1/2018-12/31/2021), controlling for numerous patient-level and logistical factors. We additionally assessed turnaround time between order and final report for various imaging modalities. RESULTS 14,204 patients were included in our analysis. Turnaround time for abbreviated MRI was significantly lower than for conventional MRI (4.40 h vs. 6.14 h, p < 0.001) with decreased impact on LOS (0.58 h vs. 2.02 h). Abbreviated MRI studies had longer turnaround time (4.40 h vs. 1.41 h, p < 0.001) and was associated with greater impact on ED LOS than non-contrast CT head (0.58 h vs. 0.00 h), however there was no significant difference in turnaround time compared to CTA head and neck (4.40 h vs. 3.86 h, p = 0.06) with similar effect on LOS (0.58 h vs. 0.53 h). Ordering both CTA and conventional MRI was associated with a greater-than-linear increase in LOS (additional 0.37 h); the same trend was not seen combining CTA and abbreviated MRI (additional 0.00 h). CONCLUSIONS In the acute settings where MRI is available, abbreviated MRI protocols may improve turnaround times and LOS compared to conventional MRI protocols. Since recent guidelines recommend MRI over CT in the evaluation of dizziness, implementation of abbreviated MRI protocols has the potential to facilitate rapid access to preferred imaging, while minimizing impact on ED workflows.
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Affiliation(s)
- Long H Tu
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, Tompkins East 2, New Haven, CT 06520, USA.
| | - Kyle Tegtmeyer
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, Tompkins East 2, New Haven, CT 06520, USA
| | - Irene Dixe de Oliveira Santo
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, Tompkins East 2, New Haven, CT 06520, USA
| | - Arjun K Venkatesh
- Department of Emergency Medicine, Yale School of Medicine, 464 Congress Ave # 260, New Haven, CT 06519, USA
| | - Howard P Forman
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, Tompkins East 2, New Haven, CT 06520, USA
| | - Amit Mahajan
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, Tompkins East 2, New Haven, CT 06520, USA
| | - Edward R Melnick
- Department of Emergency Medicine, Yale School of Medicine, 464 Congress Ave # 260, New Haven, CT 06519, USA
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20
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Kung HT, Cui SX, Kaplan JT, Joshi AA, Leahy RM, Nayak KS, Haldar JP. Diffusion tensor brain imaging at 0.55T: A feasibility study. Magn Reson Med 2024; 92:1649-1657. [PMID: 38725132 DOI: 10.1002/mrm.30156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 04/09/2024] [Accepted: 04/28/2024] [Indexed: 07/23/2024]
Abstract
PURPOSE To investigate the feasibility of diffusion tensor brain imaging at 0.55T with comparisons against 3T. METHODS Diffusion tensor imaging data with 2 mm isotropic resolution was acquired on a cohort of five healthy subjects using both 0.55T and 3T scanners. The signal-to-noise ratio (SNR) of the 0.55T data was improved using a previous SNR-enhancing joint reconstruction method that jointly reconstructs the entire set of diffusion weighted images from k-space using shared-edge constraints. Quantitative diffusion tensor parameters were estimated and compared across field strengths. We also performed a test-retest assessment of repeatability at each field strength. RESULTS After applying SNR-enhancing joint reconstruction, the diffusion tensor parameters obtained from 0.55T data were strongly correlated (R 2 ≥ 0 . 70 $$ {R}^2\ge 0.70 $$ ) with those obtained from 3T data. Test-retest analysis showed that SNR-enhancing reconstruction improved the repeatability of the 0.55T diffusion tensor parameters. CONCLUSION High-resolution in vivo diffusion MRI of the human brain is feasible at 0.55T when appropriate noise-mitigation strategies are applied.
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Affiliation(s)
- Hao-Ting Kung
- Signal and Image Processing Institute, Ming Hsieh Department of Electrical and Computer Engineering, University of Southern California, Los Angeles, California, USA
| | - Sophia X Cui
- Siemens Medical Solutions USA, Los Angeles, California, USA
| | - Jonas T Kaplan
- Brain and Creativity Institute, University of Southern California, Los Angeles, California, USA
| | - Anand A Joshi
- Signal and Image Processing Institute, Ming Hsieh Department of Electrical and Computer Engineering, University of Southern California, Los Angeles, California, USA
| | - Richard M Leahy
- Signal and Image Processing Institute, Ming Hsieh Department of Electrical and Computer Engineering, University of Southern California, Los Angeles, California, USA
| | - Krishna S Nayak
- Signal and Image Processing Institute, Ming Hsieh Department of Electrical and Computer Engineering, University of Southern California, Los Angeles, California, USA
| | - Justin P Haldar
- Signal and Image Processing Institute, Ming Hsieh Department of Electrical and Computer Engineering, University of Southern California, Los Angeles, California, USA
- Brain and Creativity Institute, University of Southern California, Los Angeles, California, USA
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21
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Suo Y, Xie X, Zhang Z, Gong X, Xu Y, Wei N, Zhu W, Qi N, Wang N, Xue B, Wang Y, Dong K, Meng X, Li Z, Zhao X, Wang Y, Jing J. Mobile 0.23 T MRI Detects Cerebral Infarction in Patients With Minor Ischemic Stroke or TIA. Stroke 2024; 55:e249-e251. [PMID: 39082136 DOI: 10.1161/strokeaha.124.047981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/28/2024]
Affiliation(s)
- Yue Suo
- Department of Neurology, Beijing Tiantan Hospital (Y.S., X.X., X.G., Y.X., K.D., X.M., Z.L., X.Z., Yongjun Wang, J.J.) Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China (Y.S., X.X., Z.Z., X.G., Y.X., N. Wei, W.Z., N.Q., K.D., X.M., Yongjun Wang, J.J.)
- Tiantan Neuroimaging Center of Excellence, Beijing, China (Y.S., Z.Z., Y.X., N. Wei, W.Z., N.Q., J.J.)
| | - Xuewei Xie
- Department of Neurology, Beijing Tiantan Hospital (Y.S., X.X., X.G., Y.X., K.D., X.M., Z.L., X.Z., Yongjun Wang, J.J.) Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China (Y.S., X.X., Z.Z., X.G., Y.X., N. Wei, W.Z., N.Q., K.D., X.M., Yongjun Wang, J.J.)
| | - Zhe Zhang
- China National Clinical Research Center for Neurological Diseases, Beijing, China (Y.S., X.X., Z.Z., X.G., Y.X., N. Wei, W.Z., N.Q., K.D., X.M., Yongjun Wang, J.J.)
- Tiantan Neuroimaging Center of Excellence, Beijing, China (Y.S., Z.Z., Y.X., N. Wei, W.Z., N.Q., J.J.)
| | - Xiping Gong
- Department of Neurology, Beijing Tiantan Hospital (Y.S., X.X., X.G., Y.X., K.D., X.M., Z.L., X.Z., Yongjun Wang, J.J.) Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China (Y.S., X.X., Z.Z., X.G., Y.X., N. Wei, W.Z., N.Q., K.D., X.M., Yongjun Wang, J.J.)
| | - Yuyuan Xu
- Department of Neurology, Beijing Tiantan Hospital (Y.S., X.X., X.G., Y.X., K.D., X.M., Z.L., X.Z., Yongjun Wang, J.J.) Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China (Y.S., X.X., Z.Z., X.G., Y.X., N. Wei, W.Z., N.Q., K.D., X.M., Yongjun Wang, J.J.)
- Tiantan Neuroimaging Center of Excellence, Beijing, China (Y.S., Z.Z., Y.X., N. Wei, W.Z., N.Q., J.J.)
| | - Ning Wei
- China National Clinical Research Center for Neurological Diseases, Beijing, China (Y.S., X.X., Z.Z., X.G., Y.X., N. Wei, W.Z., N.Q., K.D., X.M., Yongjun Wang, J.J.)
- Tiantan Neuroimaging Center of Excellence, Beijing, China (Y.S., Z.Z., Y.X., N. Wei, W.Z., N.Q., J.J.)
| | - Wanlin Zhu
- China National Clinical Research Center for Neurological Diseases, Beijing, China (Y.S., X.X., Z.Z., X.G., Y.X., N. Wei, W.Z., N.Q., K.D., X.M., Yongjun Wang, J.J.)
- Tiantan Neuroimaging Center of Excellence, Beijing, China (Y.S., Z.Z., Y.X., N. Wei, W.Z., N.Q., J.J.)
| | - Nan Qi
- China National Clinical Research Center for Neurological Diseases, Beijing, China (Y.S., X.X., Z.Z., X.G., Y.X., N. Wei, W.Z., N.Q., K.D., X.M., Yongjun Wang, J.J.)
- Tiantan Neuroimaging Center of Excellence, Beijing, China (Y.S., Z.Z., Y.X., N. Wei, W.Z., N.Q., J.J.)
| | - Ning Wang
- Department of Neurosurgery, Xuanwu Hospital (N. Wang) Capital Medical University, Beijing, China
| | - Bingshan Xue
- Ray Plus Medical Technology, Beijing, China (B.X., Yihuai Wang)
| | - Yihuai Wang
- Ray Plus Medical Technology, Beijing, China (B.X., Yihuai Wang)
| | - Kehui Dong
- Department of Neurology, Beijing Tiantan Hospital (Y.S., X.X., X.G., Y.X., K.D., X.M., Z.L., X.Z., Yongjun Wang, J.J.) Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China (Y.S., X.X., Z.Z., X.G., Y.X., N. Wei, W.Z., N.Q., K.D., X.M., Yongjun Wang, J.J.)
| | - Xia Meng
- Department of Neurology, Beijing Tiantan Hospital (Y.S., X.X., X.G., Y.X., K.D., X.M., Z.L., X.Z., Yongjun Wang, J.J.) Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China (Y.S., X.X., Z.Z., X.G., Y.X., N. Wei, W.Z., N.Q., K.D., X.M., Yongjun Wang, J.J.)
| | - Zixiao Li
- Department of Neurology, Beijing Tiantan Hospital (Y.S., X.X., X.G., Y.X., K.D., X.M., Z.L., X.Z., Yongjun Wang, J.J.) Capital Medical University, Beijing, China
| | - Xingquan Zhao
- Department of Neurology, Beijing Tiantan Hospital (Y.S., X.X., X.G., Y.X., K.D., X.M., Z.L., X.Z., Yongjun Wang, J.J.) Capital Medical University, Beijing, China
| | - Yongjun Wang
- Department of Neurology, Beijing Tiantan Hospital (Y.S., X.X., X.G., Y.X., K.D., X.M., Z.L., X.Z., Yongjun Wang, J.J.) Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China (Y.S., X.X., Z.Z., X.G., Y.X., N. Wei, W.Z., N.Q., K.D., X.M., Yongjun Wang, J.J.)
| | - Jing Jing
- Department of Neurology, Beijing Tiantan Hospital (Y.S., X.X., X.G., Y.X., K.D., X.M., Z.L., X.Z., Yongjun Wang, J.J.) Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China (Y.S., X.X., Z.Z., X.G., Y.X., N. Wei, W.Z., N.Q., K.D., X.M., Yongjun Wang, J.J.)
- Tiantan Neuroimaging Center of Excellence, Beijing, China (Y.S., Z.Z., Y.X., N. Wei, W.Z., N.Q., J.J.)
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22
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Zhao Y, Bhosale AA, Zhang X. Coupled stack-up volume RF coils for low-field open MR imaging. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.08.30.24312851. [PMID: 39252906 PMCID: PMC11383509 DOI: 10.1101/2024.08.30.24312851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/11/2024]
Abstract
Background Low-field open magnetic resonance imaging (MRI) systems, typically operating at magnetic field strengths below 1 Tesla, has greatly expanded the accessibility of MRI technology to meet a wide range of patient needs. However, the inherent challenges of low-field MRI, such as limited signal-to-noise ratios and limited availability of dedicated radiofrequency (RF) coils, have prompted the need for innovative coil designs that can improve imaging quality and diagnostic capabilities. Purpose In response to these challenges, we introduce the coupled stack-up volume coil, a novel RF coil design that addresses the shortcomings of conventional birdcage in the context of low-field open MRI. Methods The proposed coupled stack-up volume coil design utilizes a unique architecture that optimizes both transmit/receive efficiency and RF field homogeneity and offers the advantage of a simple design and construction, making it a practical and feasible solution for low-field MRI applications. This paper presents a comprehensive exploration of the theoretical framework, design considerations, and experimental validation of this innovative coil design. Results We demonstrate the superior performance of the coupled stack-up volume coil in achieving 47.7% higher transmit/receive efficiency and 68% more uniform magnetic field distribution compared to traditional birdcage coils in electromagnetic simulations. Bench tests results show that the B1 field efficiency of coupled stack-up volume coil is 57.3% higher compared with that of conventional birdcage coil. Conclusions The proposed coupled stack-up volume coil outperforms the conventional birdcage coil in terms of B1 efficiency, imaging coverage, and low-frequency operation capability. This design provides a robust and simple solution to low-field MR RF coil design.
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Affiliation(s)
- Yunkun Zhao
- Department of Biomedical Engineering, State University of New York at Buffalo, Buffalo, NY, United States
| | - Aditya A Bhosale
- Department of Biomedical Engineering, State University of New York at Buffalo, Buffalo, NY, United States
| | - Xiaoliang Zhang
- Department of Biomedical Engineering, State University of New York at Buffalo, Buffalo, NY, United States
- Department of Electrical Engineering, State University of New York at Buffalo, Buffalo, NY, United States
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23
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Balaji S, Wiley N, Poorman ME, Kolind SH. Low-field MRI for use in neurological diseases. Curr Opin Neurol 2024; 37:381-391. [PMID: 38813835 DOI: 10.1097/wco.0000000000001282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
PURPOSE OF REVIEW To review recent clinical uses of low-field magnetic resonance imaging (MRI) to guide incorporation into neurological practice. RECENT FINDINGS Use of low-field MRI has been demonstrated in applications including tumours, vascular pathologies, multiple sclerosis, brain injury, and paediatrics. Safety, workflow, and image quality have also been evaluated. SUMMARY Low-field MRI has the potential to increase access to critical brain imaging for patients who otherwise may not obtain imaging in a timely manner. This includes areas such as the intensive care unit and emergency room, where patients could be imaged at the point of care rather than be transported to the MRI scanner. Such systems are often more affordable than conventional systems, allowing them to be more easily deployed in resource constrained settings. A variety of systems are available on the market or in a research setting and are currently being used to determine clinical uses for these devices. The utility of such devices must be fully evaluated in clinical scenarios before adoption into standard practice can be achieved. This review summarizes recent clinical uses of low-field MR as well as safety, workflows, and image quality to aid practitioners in assessing this new technology.
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Affiliation(s)
- Sharada Balaji
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Neale Wiley
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada
| | | | - Shannon H Kolind
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Medicine (Neurology)
- Department of Radiology
- International Collaboration on Repair Discoveries, Blusson Spinal Cord Centre, University of British Columbia, Vancouver, British Columbia, Canada
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24
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Sorby-Adams A, Guo J, de Havenon A, Payabvash S, Sze G, Pinter NK, Jaikumar V, Siddiqui A, Baldassano S, Garcia-Guarniz AL, Zabinska J, Lalwani D, Peasley E, Goldstein JN, Nelson OK, Schaefer PW, Wira CR, Pitts J, Lee V, Muir KW, Nimjee SM, Kirsch J, Eugenio Iglesias J, Rosen MS, Sheth KN, Kimberly WT. Diffusion-Weighted Imaging Fluid-Attenuated Inversion Recovery Mismatch on Portable, Low-Field Magnetic Resonance Imaging Among Acute Stroke Patients. Ann Neurol 2024; 96:321-331. [PMID: 38738750 PMCID: PMC11293843 DOI: 10.1002/ana.26954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 04/26/2024] [Accepted: 04/28/2024] [Indexed: 05/14/2024]
Abstract
OBJECTIVE For stroke patients with unknown time of onset, mismatch between diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI) can guide thrombolytic intervention. However, access to MRI for hyperacute stroke is limited. Here, we sought to evaluate whether a portable, low-field (LF)-MRI scanner can identify DWI-FLAIR mismatch in acute ischemic stroke. METHODS Eligible patients with a diagnosis of acute ischemic stroke underwent LF-MRI acquisition on a 0.064-T scanner within 24 h of last known well. Qualitative and quantitative metrics were evaluated. Two trained assessors determined the visibility of stroke lesions on LF-FLAIR. An image coregistration pipeline was developed, and the LF-FLAIR signal intensity ratio (SIR) was derived. RESULTS The study included 71 patients aged 71 ± 14 years and a National Institutes of Health Stroke Scale of 6 (interquartile range 3-14). The interobserver agreement for identifying visible FLAIR hyperintensities was high (κ = 0.85, 95% CI 0.70-0.99). Visual DWI-FLAIR mismatch had a 60% sensitivity and 82% specificity for stroke patients <4.5 h, with a negative predictive value of 93%. LF-FLAIR SIR had a mean value of 1.18 ± 0.18 <4.5 h, 1.24 ± 0.39 4.5-6 h, and 1.40 ± 0.23 >6 h of stroke onset. The optimal cut-point for LF-FLAIR SIR was 1.15, with 85% sensitivity and 70% specificity. A cut-point of 6.6 h was established for a FLAIR SIR <1.15, with an 89% sensitivity and 62% specificity. INTERPRETATION A 0.064-T portable LF-MRI can identify DWI-FLAIR mismatch among patients with acute ischemic stroke. Future research is needed to prospectively validate thresholds and evaluate a role of LF-MRI in guiding thrombolysis among stroke patients with uncertain time of onset. ANN NEUROL 2024;96:321-331.
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Affiliation(s)
- Annabel Sorby-Adams
- Department of Neurology and the Center for Genomic Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Jennifer Guo
- Department of Neurology and the Center for Genomic Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Adam de Havenon
- Department of Neurology, Yale Center for Brain & Mind Health, Yale School of Medicine, New Haven, CT, USA
| | - Seyedmehdi Payabvash
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA
| | - Gordon Sze
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA
| | - Nandor K. Pinter
- Department of Radiology, Jacobs School of Medicine & Biomedical Sciences, University of Buffalo, Buffalo, New York, USA
- Department of Neurosurgery, Jacobs School of Medicine & Biomedical Sciences, University of Buffalo, Buffalo, New York, USA
| | - Vinay Jaikumar
- Department of Neurosurgery, Jacobs School of Medicine & Biomedical Sciences, University of Buffalo, Buffalo, New York, USA
| | - Adnan Siddiqui
- Department of Neurosurgery, Jacobs School of Medicine & Biomedical Sciences, University of Buffalo, Buffalo, New York, USA
| | - Steven Baldassano
- Division of Neuroradiology, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Ana-Lucia Garcia-Guarniz
- Department of Neurology and the Center for Genomic Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Julia Zabinska
- Department of Neurology, Yale Center for Brain & Mind Health, Yale School of Medicine, New Haven, CT, USA
| | - Dheeraj Lalwani
- Department of Neurology, Yale Center for Brain & Mind Health, Yale School of Medicine, New Haven, CT, USA
| | - Emma Peasley
- Department of Neurology, Yale Center for Brain & Mind Health, Yale School of Medicine, New Haven, CT, USA
| | - Joshua N. Goldstein
- Department of Emergency Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Olivia K. Nelson
- Department of Emergency Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Pamela W. Schaefer
- Division of Neuroradiology, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Charles R. Wira
- Department of Emergency Medicine, Yale New Haven Hospital and Yale School of Medicine, New Haven, Connecticut, USA
| | - John Pitts
- Hyperfine Incorporated, Guilford, Connecticut, USA
| | - Vivien Lee
- Wexner Medical Center, Ohio State University, Columbus, Ohio, USA
| | - Keith W. Muir
- School of Psychology and Neuroscience, University of Glasgow, Glasgow, UK
| | - Shahid M. Nimjee
- Wexner Medical Center, Ohio State University, Columbus, Ohio, USA
| | - John Kirsch
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Juan Eugenio Iglesias
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
- Centre for Medical Image Computing, University College London, London, UK
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Matthew S. Rosen
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Kevin N. Sheth
- Department of Neurology, Yale Center for Brain & Mind Health, Yale School of Medicine, New Haven, CT, USA
| | - W. Taylor Kimberly
- Department of Neurology and the Center for Genomic Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
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Lee H, Lee J, Jung D, Oh H, Shin H, Choi B. Neuroprotection of Transcranial Cortical and Peripheral Somatosensory Electrical Stimulation by Modulating a Common Neuronal Death Pathway in Mice with Ischemic Stroke. Int J Mol Sci 2024; 25:7546. [PMID: 39062789 PMCID: PMC11277498 DOI: 10.3390/ijms25147546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2024] [Revised: 07/05/2024] [Accepted: 07/08/2024] [Indexed: 07/28/2024] Open
Abstract
Therapeutic electrical stimulation, such as transcranial cortical stimulation and peripheral somatosensory stimulation, is used to improve motor function in patients with stroke. We hypothesized that these stimulations exert neuroprotective effects during the subacute phase of ischemic stroke by regulating novel common signaling pathways. Male C57BL/6J mouse models of ischemic stroke were treated with high-definition (HD)-transcranial alternating current stimulation (tACS; 20 Hz, 89.1 A/mm2), HD-transcranial direct current stimulation (tDCS; intensity, 55 A/mm2; charge density, 66,000 C/m2), or electroacupuncture (EA, 2 Hz, 1 mA) in the early stages of stroke. The therapeutic effects were assessed using behavioral motor function tests. The underlying mechanisms were determined using transcriptomic and other biomedical analyses. All therapeutic electrical tools alleviated the motor dysfunction caused by ischemic stroke insults. We focused on electrically stimulating common genes involved in apoptosis and cell death using transcriptome analysis and chose 11 of the most potent targets (Trem2, S100a9, Lgals3, Tlr4, Myd88, NF-kB, STAT1, IL-6, IL-1β, TNF-α, and Iba1). Subsequent investigations revealed that electrical stimulation modulated inflammatory cytokines, including IL-1β and TNF-α, by regulating STAT1 and NF-kB activation, especially in amoeboid microglia; moreover, electrical stimulation enhanced neuronal survival by activating neurotrophic factors, including BDNF and FGF9. Therapeutic electrical stimulation applied to the transcranial cortical- or periphery-nerve level to promote functional recovery may improve neuroprotection by modulating a common neuronal death pathway and upregulating neurotrophic factors. Therefore, combining transcranial cortical and peripheral somatosensory stimulation may exert a synergistic neuroprotective effect, further enhancing the beneficial effects on motor deficits in patients with ischemic stroke.
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Affiliation(s)
- Hongju Lee
- Department of Korean Medical Science, School of Korean Medicine, Pusan National University, Yangsan 50612, Republic of Korea; (H.L.); (J.L.); (D.J.); (H.O.); (H.S.)
| | - Juyeon Lee
- Department of Korean Medical Science, School of Korean Medicine, Pusan National University, Yangsan 50612, Republic of Korea; (H.L.); (J.L.); (D.J.); (H.O.); (H.S.)
- Graduate Training Program of Korean Medical Therapeutics for Healthy Aging, Pusan National University, Yangsan 50612, Republic of Korea
| | - Dahee Jung
- Department of Korean Medical Science, School of Korean Medicine, Pusan National University, Yangsan 50612, Republic of Korea; (H.L.); (J.L.); (D.J.); (H.O.); (H.S.)
- Graduate Training Program of Korean Medical Therapeutics for Healthy Aging, Pusan National University, Yangsan 50612, Republic of Korea
| | - Harim Oh
- Department of Korean Medical Science, School of Korean Medicine, Pusan National University, Yangsan 50612, Republic of Korea; (H.L.); (J.L.); (D.J.); (H.O.); (H.S.)
- Graduate Training Program of Korean Medical Therapeutics for Healthy Aging, Pusan National University, Yangsan 50612, Republic of Korea
| | - Hwakyoung Shin
- Department of Korean Medical Science, School of Korean Medicine, Pusan National University, Yangsan 50612, Republic of Korea; (H.L.); (J.L.); (D.J.); (H.O.); (H.S.)
- Graduate Training Program of Korean Medical Therapeutics for Healthy Aging, Pusan National University, Yangsan 50612, Republic of Korea
| | - Byungtae Choi
- Department of Korean Medical Science, School of Korean Medicine, Pusan National University, Yangsan 50612, Republic of Korea; (H.L.); (J.L.); (D.J.); (H.O.); (H.S.)
- Graduate Training Program of Korean Medical Therapeutics for Healthy Aging, Pusan National University, Yangsan 50612, Republic of Korea
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Murali S, Ding H, Adedeji F, Qin C, Obungoloch J, Asllani I, Anazodo U, Ntusi NAB, Mammen R, Niendorf T, Adeleke S. Bringing MRI to low- and middle-income countries: Directions, challenges and potential solutions. NMR IN BIOMEDICINE 2024; 37:e4992. [PMID: 37401341 DOI: 10.1002/nbm.4992] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 05/27/2023] [Accepted: 05/30/2023] [Indexed: 07/05/2023]
Abstract
The global disparity of magnetic resonance imaging (MRI) is a major challenge, with many low- and middle-income countries (LMICs) experiencing limited access to MRI. The reasons for limited access are technological, economic and social. With the advancement of MRI technology, we explore why these challenges still prevail, highlighting the importance of MRI as the epidemiology of disease changes in LMICs. In this paper, we establish a framework to develop MRI with these challenges in mind and discuss the different aspects of MRI development, including maximising image quality using cost-effective components, integrating local technology and infrastructure and implementing sustainable practices. We also highlight the current solutions-including teleradiology, artificial intelligence and doctor and patient education strategies-and how these might be further improved to achieve greater access to MRI.
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Affiliation(s)
- Sanjana Murali
- School of Medicine, Faculty of Medicine, Imperial College London, London, UK
| | - Hao Ding
- School of Medicine, Faculty of Medicine, Imperial College London, London, UK
| | - Fope Adedeji
- School of Medicine, Faculty of Medicine, University College London, London, UK
| | - Cathy Qin
- Department of Imaging, Imperial College Healthcare NHS Trust, London, UK
| | - Johnes Obungoloch
- Department of Biomedical Engineering, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Iris Asllani
- Department of Biomedical Engineering, Rochester Institute of Technology, Rochester, New York, USA
| | - Udunna Anazodo
- Department of Medical Biophysics, Western University, London, Ontario, Canada
- The Research Institute of London Health Sciences Centre and St. Joseph's Health Care, London, Ontario, Canada
| | - Ntobeko A B Ntusi
- Department of Medicine, University of Cape Town and Groote Schuur Hospital, Cape Town, South Africa
- South African Medical Research Council Extramural Unit on Intersection of Noncommunicable Diseases and Infectious Diseases, Cape Town, South Africa
| | - Regina Mammen
- Department of Cardiology, The Essex Cardiothoracic Centre, Basildon, UK
| | - Thoralf Niendorf
- Berlin Ultrahigh Field Facility (BUFF), Max-Delbrück Centre for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Sola Adeleke
- School of Cancer & Pharmaceutical Sciences, King's College London, London, UK
- High Dimensional Neuro-oncology, University College London Queen Square Institute of Neurology, Faculty of Brain Sciences, University College London, London, UK
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27
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Zhao Y, Xiao L, Hu J, Wu EX. Robust EMI elimination for RF shielding-free MRI through deep learning direct MR signal prediction. Magn Reson Med 2024; 92:112-127. [PMID: 38376455 DOI: 10.1002/mrm.30046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 01/23/2024] [Accepted: 01/23/2024] [Indexed: 02/21/2024]
Abstract
PURPOSE To develop a new electromagnetic interference (EMI) elimination strategy for RF shielding-free MRI via active EMI sensing and deep learning direct MR signal prediction (Deep-DSP). METHODS Deep-DSP is proposed to directly predict EMI-free MR signals. During scanning, MRI receive coil and EMI sensing coils simultaneously sample data within two windows (i.e., for MR data and EMI characterization data acquisition, respectively). Afterward, a residual U-Net model is trained using synthetic MRI receive coil data and EMI sensing coil data acquired during EMI signal characterization window, to predict EMI-free MR signals from signals acquired by MRI receive and EMI sensing coils. The trained model is then used to directly predict EMI-free MR signals from data acquired by MRI receive and sensing coils during the MR signal-acquisition window. This strategy was evaluated on an ultralow-field 0.055T brain MRI scanner without any RF shielding and a 1.5T whole-body scanner with incomplete RF shielding. RESULTS Deep-DSP accurately predicted EMI-free MR signals in presence of strong EMI. It outperformed recently developed EDITER and convolutional neural network methods, yielding better EMI elimination and enabling use of few EMI sensing coils. Furthermore, it could work well without dedicated EMI characterization data. CONCLUSION Deep-DSP presents an effective EMI elimination strategy that outperforms existing methods, advancing toward truly portable and patient-friendly MRI. It exploits electromagnetic coupling between MRI receive and EMI sensing coils as well as typical MR signal characteristics. Despite its deep learning nature, Deep-DSP framework is computationally simple and efficient.
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Affiliation(s)
- Yujiao Zhao
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, People's Republic of China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, People's Republic of China
| | - Linfang Xiao
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, People's Republic of China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, People's Republic of China
| | - Jiahao Hu
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, People's Republic of China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, People's Republic of China
| | - Ed X Wu
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, People's Republic of China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, People's Republic of China
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28
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Samardzija A, Selvaganesan K, Zhang HZ, Sun H, Sun C, Ha Y, Galiana G, Constable RT. Low-Field, Low-Cost, Point-of-Care Magnetic Resonance Imaging. Annu Rev Biomed Eng 2024; 26:67-91. [PMID: 38211326 DOI: 10.1146/annurev-bioeng-110122-022903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2024]
Abstract
Low-field magnetic resonance imaging (MRI) has recently experienced a renaissance that is largely attributable to the numerous technological advancements made in MRI, including optimized pulse sequences, parallel receive and compressed sensing, improved calibrations and reconstruction algorithms, and the adoption of machine learning for image postprocessing. This new attention on low-field MRI originates from a lack of accessibility to traditional MRI and the need for affordable imaging. Low-field MRI provides a viable option due to its lack of reliance on radio-frequency shielding rooms, expensive liquid helium, and cryogen quench pipes. Moreover, its relatively small size and weight allow for easy and affordable installation in most settings. Rather than replacing conventional MRI, low-field MRI will provide new opportunities for imaging both in developing and developed countries. This article discusses the history of low-field MRI, low-field MRI hardware and software, current devices on the market, advantages and disadvantages, and low-field MRI's global potential.
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Affiliation(s)
- Anja Samardzija
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut, USA;
| | - Kartiga Selvaganesan
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut, USA;
| | - Horace Z Zhang
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut, USA;
| | - Heng Sun
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut, USA;
| | - Chenhao Sun
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA
| | - Yonghyun Ha
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA
| | - Gigi Galiana
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut, USA;
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA
| | - R Todd Constable
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut, USA;
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, Connecticut, USA
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29
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Zhao Y, Xiao L, Liu Y, Leong AT, Wu EX. Electromagnetic interference elimination via active sensing and deep learning prediction for radiofrequency shielding-free MRI. NMR IN BIOMEDICINE 2024; 37:e4956. [PMID: 37088894 DOI: 10.1002/nbm.4956] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 04/12/2023] [Accepted: 04/19/2023] [Indexed: 05/03/2023]
Abstract
At present, MRI scans are typically performed inside fully enclosed radiofrequency (RF) shielding rooms, posing stringent installation requirements and causing patient discomfort. We aim to eliminate electromagnetic interference (EMI) for MRI with no or incomplete RF shielding. In this study, a method of active sensing and deep learning EMI prediction is presented to model, predict, and remove EMI signal components from acquired MRI signals. Specifically, during each MRI scan, separate EMI-sensing coils placed in various locations are utilized to simultaneously sample external and internal EMI signals within two windows (for both conventional MRI signal acquisition and EMI characterization acquisition). A convolution neural network model is trained using the EMI characterization data to relate EMI signals detected by EMI-sensing coils to EMI signals in the MRI receive coil. This model is then used to retrospectively predict and remove EMI signal components detected by the MRI receive coil during the MRI signal acquisition window. This strategy was implemented on a low-cost ultralow-field 0.055 T permanent magnet MRI scanner without RF shielding. It produced final image signal-to-noise ratios that were comparable with those obtained using a fully enclosed RF shielding cage, and outperformed existing analytical EMI elimination methods (i.e., spectral domain transfer function and external dynamic interference estimation and removal [EDITER] methods). A preliminary experiment also demonstrated its applicability on a 1.5 T superconducting magnet MRI scanner with incomplete RF shielding. Altogether, the results demonstrated that the proposed method was highly effective in predicting and removing various EMI signals from both external environments and internal scanner electronics at both 0.055 T (2.3 MHz) and 1.5 T (63.9 MHz). The proposed strategy enables shielding-free MRI. The concept is relatively simple and is potentially applicable to other RF signal detection scenarios in the presence of external and/or internal EMI.
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Affiliation(s)
- Yujiao Zhao
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, SAR, China
| | - Linfang Xiao
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, SAR, China
| | - Yilong Liu
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, SAR, China
| | - Alex T Leong
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, SAR, China
| | - Ed X Wu
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, SAR, China
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30
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Altaf A, Shakir M, Irshad HA, Atif S, Kumari U, Islam O, Kimberly WT, Knopp E, Truwit C, Siddiqui K, Enam SA. Applications, limitations and advancements of ultra-low-field magnetic resonance imaging: A scoping review. Surg Neurol Int 2024; 15:218. [PMID: 38974534 PMCID: PMC11225429 DOI: 10.25259/sni_162_2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Accepted: 05/17/2024] [Indexed: 07/09/2024] Open
Abstract
BACKGROUND Ultra-low-field magnetic resonance imaging (ULF-MRI) has emerged as an alternative with several portable clinical applications. This review aims to comprehensively explore its applications, potential limitations, technological advancements, and expert recommendations. METHODS A review of the literature was conducted across medical databases to identify relevant studies. Articles on clinical usage of ULF-MRI were included, and data regarding applications, limitations, and advancements were extracted. A total of 25 articles were included for qualitative analysis. RESULTS The review reveals ULF-MRI efficacy in intensive care settings and intraoperatively. Technological strides are evident through innovative reconstruction techniques and integration with machine learning approaches. Additional advantages include features such as portability, cost-effectiveness, reduced power requirements, and improved patient comfort. However, alongside these strengths, certain limitations of ULF-MRI were identified, including low signal-to-noise ratio, limited resolution and length of scanning sequences, as well as variety and absence of regulatory-approved contrast-enhanced imaging. Recommendations from experts emphasize optimizing imaging quality, including addressing signal-to-noise ratio (SNR) and resolution, decreasing the length of scan time, and expanding point-of-care magnetic resonance imaging availability. CONCLUSION This review summarizes the potential of ULF-MRI. The technology's adaptability in intensive care unit settings and its diverse clinical and surgical applications, while accounting for SNR and resolution limitations, highlight its significance, especially in resource-limited settings. Technological advancements, alongside expert recommendations, pave the way for refining and expanding ULF-MRI's utility. However, adequate training is crucial for widespread utilization.
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Affiliation(s)
- Ahmed Altaf
- Department of Surgery, Section of Neurosurgery, Aga Khan University Hospital, Karachi, Sindh, Pakistan
| | - Muhammad Shakir
- Department of Surgery, Section of Neurosurgery, Aga Khan University Hospital, Karachi, Sindh, Pakistan
| | | | - Shiza Atif
- Medical College, Aga Khan University Hospital, Karachi, Sindh, Pakistan
| | - Usha Kumari
- Medical College, Peoples University of Medical and Health Sciences for Women, Karachi, Sindh, Pakistan
| | - Omar Islam
- Department of Diagnostic Radiology, Queen’s University, Kingston General Hospital, Kingston, Canada
| | - W. Taylor Kimberly
- Department of Neurology, Massachusetts General Hospital, Boston, United States
| | | | | | | | - S. Ather Enam
- Department of Surgery, Section of Neurosurgery, Aga Khan University Hospital, Karachi, Sindh, Pakistan
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Iqbal N, Brittin DO, Daluwathumullagamage PJ, Alam MS, Senanayake IM, Gafar AT, Siraj Z, Petrilla A, Pugh M, Tonazzi B, Ragunathan S, Poorman ME, Sacolick L, Theis T, Rosen MS, Chekmenev EY, Goodson BM. Toward Next-Generation Molecular Imaging with a Clinical Low-Field (0.064 T) Point-of-Care MRI Scanner. Anal Chem 2024; 96:10348-10355. [PMID: 38857182 DOI: 10.1021/acs.analchem.4c01299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2024]
Abstract
Low-field (LF) MRI promises soft-tissue imaging without the expensive, immobile magnets of clinical scanners but generally suffers from limited detection sensitivity and contrast. The sensitivity boost provided by hyperpolarization can thus be highly synergistic with LF MRI. Initial efforts to integrate a continuous-bubbling SABRE (signal amplification by reversible exchange) hyperpolarization setup with a portable, point-of-care 64 mT clinical MRI scanner are reported. Results from 1H SABRE MRI of pyrazine and nicotinamide are compared with those of benchtop NMR spectroscopy. Comparison with MRI signals from samples with known H2O/D2O ratios allowed quantification of the SABRE enhancements of imaged samples with various substrate concentrations (down to 3 mM). Respective limits of detection and quantification of 3.3 and 10.1 mM were determined with pyrazine 1H polarization (PH) enhancements of ∼1900 (PH ∼0.04%), supporting ongoing and envisioned efforts to realize SABRE-enabled MRI-based molecular imaging.
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Affiliation(s)
- Nadiya Iqbal
- School of Chemical and Biomolecular Sciences, Southern Illinois University, Carbondale, Illinois 62901, United States
| | - Drew O Brittin
- School of Chemical and Biomolecular Sciences, Southern Illinois University, Carbondale, Illinois 62901, United States
| | | | - Md Shahabuddin Alam
- School of Chemical and Biomolecular Sciences, Southern Illinois University, Carbondale, Illinois 62901, United States
| | - Ishani M Senanayake
- School of Chemical and Biomolecular Sciences, Southern Illinois University, Carbondale, Illinois 62901, United States
| | - A Tobi Gafar
- School of Chemical and Biomolecular Sciences, Southern Illinois University, Carbondale, Illinois 62901, United States
| | - Zahid Siraj
- School of Chemical and Biomolecular Sciences, Southern Illinois University, Carbondale, Illinois 62901, United States
| | - Anthony Petrilla
- School of Chemical and Biomolecular Sciences, Southern Illinois University, Carbondale, Illinois 62901, United States
| | - Margaret Pugh
- School of Chemical and Biomolecular Sciences, Southern Illinois University, Carbondale, Illinois 62901, United States
| | - Brockton Tonazzi
- School of Medicine, Southern Illinois University, Carbondale, Illinois 62901, United States
| | | | | | - Laura Sacolick
- Hyperfine Inc., Guilford, Connecticut 06437, United States
| | - Thomas Theis
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Matthew S Rosen
- A.A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02129, United States
| | - Eduard Y Chekmenev
- Department of Chemistry, Integrative Biosciences (IBio), Karmanos Cancer Institute (KCI), Wayne State University, Detroit, Michigan 48202, United States
| | - Boyd M Goodson
- School of Chemical and Biomolecular Sciences, Southern Illinois University, Carbondale, Illinois 62901, United States
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32
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Chen Q, Zhang S, Liu W, Sun X, Luo Y, Sun X. Application of emerging technologies in ischemic stroke: from clinical study to basic research. Front Neurol 2024; 15:1400469. [PMID: 38915803 PMCID: PMC11194379 DOI: 10.3389/fneur.2024.1400469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Accepted: 05/24/2024] [Indexed: 06/26/2024] Open
Abstract
Stroke is a primary cause of noncommunicable disease-related death and disability worldwide. The most common form, ischemic stroke, is increasing in incidence resulting in a significant burden on patients and society. Urgent action is thus needed to address preventable risk factors and improve treatment methods. This review examines emerging technologies used in the management of ischemic stroke, including neuroimaging, regenerative medicine, biology, and nanomedicine, highlighting their benefits, clinical applications, and limitations. Additionally, we suggest strategies for technological development for the prevention, diagnosis, and treatment of ischemic stroke.
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Affiliation(s)
- Qiuyan Chen
- Institute of Medicinal Plant Development, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
- Beijing Key Laboratory of Innovative Drug Discovery of Traditional Chinese Medicine (Natural Medicine) and Translational Medicine, Beijing, China
- Key Laboratory of Bioactive Substances and Resource Utilization of Chinese Herbal Medicine, Ministry of Education, Beijing, China
| | - Shuxia Zhang
- Institute of Medicinal Plant Development, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
- Beijing Key Laboratory of Innovative Drug Discovery of Traditional Chinese Medicine (Natural Medicine) and Translational Medicine, Beijing, China
- Key Laboratory of Bioactive Substances and Resource Utilization of Chinese Herbal Medicine, Ministry of Education, Beijing, China
| | - Wenxiu Liu
- Institute of Medicinal Plant Development, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
- Beijing Key Laboratory of Innovative Drug Discovery of Traditional Chinese Medicine (Natural Medicine) and Translational Medicine, Beijing, China
- Key Laboratory of Bioactive Substances and Resource Utilization of Chinese Herbal Medicine, Ministry of Education, Beijing, China
| | - Xiao Sun
- Institute of Medicinal Plant Development, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
- Beijing Key Laboratory of Innovative Drug Discovery of Traditional Chinese Medicine (Natural Medicine) and Translational Medicine, Beijing, China
- Key Laboratory of Bioactive Substances and Resource Utilization of Chinese Herbal Medicine, Ministry of Education, Beijing, China
| | - Yun Luo
- Institute of Medicinal Plant Development, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
- Beijing Key Laboratory of Innovative Drug Discovery of Traditional Chinese Medicine (Natural Medicine) and Translational Medicine, Beijing, China
- Key Laboratory of Bioactive Substances and Resource Utilization of Chinese Herbal Medicine, Ministry of Education, Beijing, China
| | - Xiaobo Sun
- Institute of Medicinal Plant Development, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
- Beijing Key Laboratory of Innovative Drug Discovery of Traditional Chinese Medicine (Natural Medicine) and Translational Medicine, Beijing, China
- Key Laboratory of Bioactive Substances and Resource Utilization of Chinese Herbal Medicine, Ministry of Education, Beijing, China
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33
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Sarraj A, Pujara DK, Campbell BC. Current State of Evidence for Neuroimaging Paradigms in Management of Acute Ischemic Stroke. Ann Neurol 2024; 95:1017-1034. [PMID: 38606939 DOI: 10.1002/ana.26925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 03/08/2024] [Accepted: 03/11/2024] [Indexed: 04/13/2024]
Abstract
Stroke is the chief differential diagnosis in patient presenting to the emergency room with abrupt onset focal neurological deficits. Neuroimaging, including non-contrast computed tomography (CT), magnetic resonance imaging (MRI), vascular and perfusion imaging, is a cornerstone in the diagnosis and treatment decision-making. This review examines the current state of evidence behind the different imaging paradigms for acute ischemic stroke diagnosis and treatment, including current recommendations from the guidelines. Non-contrast CT brain, or in some centers MRI, can help differentiate ischemic stroke and intracerebral hemorrhage (ICH), a pivotal juncture in stroke diagnosis and treatment algorithm, especially for early window thrombolytics. Advanced imaging such as MRI or perfusion imaging can also assist making a diagnosis of ischemic stroke versus mimics such as migraine, Todd's paresis, or functional disorders. Identification of medium-large vessel occlusions with CT or MR angiography triggers consideration of endovascular thrombectomy (EVT), with additional perfusion imaging help identify salvageable brain tissue in patients who are likely to benefit from reperfusion therapies, particularly in the ≥6 h window. We also review recent advances in neuroimaging and ongoing trials in key therapeutic areas and their imaging selection criteria to inform the readers on potential future transitions into use of neuroimaging for stroke diagnosis and treatment decision making. ANN NEUROL 2024;95:1017-1034.
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Affiliation(s)
- Amrou Sarraj
- University Hospital Cleveland Medical Center-Case Western Reserve University, Neurology, Cleveland, Ohio, USA
| | - Deep K Pujara
- University Hospital Cleveland Medical Center-Case Western Reserve University, Neurology, Cleveland, Ohio, USA
| | - Bruce Cv Campbell
- The Royal Melbourne Hospital-The Florey Institute for Neuroscience and Mental Health, Medicine and Neurology, Parkville, Australia
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Zhao Y, Ding Y, Lau V, Man C, Su S, Xiao L, Leong ATL, Wu EX. Whole-body magnetic resonance imaging at 0.05 Tesla. Science 2024; 384:eadm7168. [PMID: 38723062 DOI: 10.1126/science.adm7168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 03/19/2024] [Indexed: 05/31/2024]
Abstract
Despite a half-century of advancements, global magnetic resonance imaging (MRI) accessibility remains limited and uneven, hindering its full potential in health care. Initially, MRI development focused on low fields around 0.05 Tesla, but progress halted after the introduction of the 1.5 Tesla whole-body superconducting scanner in 1983. Using a permanent 0.05 Tesla magnet and deep learning for electromagnetic interference elimination, we developed a whole-body scanner that operates using a standard wall power outlet and without radiofrequency and magnetic shielding. We demonstrated its wide-ranging applicability for imaging various anatomical structures. Furthermore, we developed three-dimensional deep learning reconstruction to boost image quality by harnessing extensive high-field MRI data. These advances pave the way for affordable deep learning-powered ultra-low-field MRI scanners, addressing unmet clinical needs in diverse health care settings worldwide.
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Affiliation(s)
- Yujiao Zhao
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Ye Ding
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Vick Lau
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Christopher Man
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Shi Su
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Linfang Xiao
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Alex T L Leong
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Ed X Wu
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
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35
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Anazodo UC, Plessis SD. Imaging without barriers. Science 2024; 384:623-624. [PMID: 38723100 DOI: 10.1126/science.adp0670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
Low-field magnetic resonance imaging can be engineered for widespread point-of-care diagnostics.
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Affiliation(s)
- Udunna C Anazodo
- McConnell Brain Imaging Centre, Department of Neurology and Neurosurgery, Montreal Neurological Insitute, McGill University, Montreal, QC, Canada
- Medical Artificial Intelligence Laboratory, Crestview Radiology Ltd., Lagos, Nigeria
| | - Stefan du Plessis
- Department of Psychiatry, Stellenbosch University, Cape Town, South Africa
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Nieboer KH. Rethinking the shoe: is CT perfusion the optimal screening tool for acute stroke patients? Eur Radiol 2024; 34:3059-3060. [PMID: 37851121 PMCID: PMC11126433 DOI: 10.1007/s00330-023-10336-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 08/10/2023] [Accepted: 08/18/2023] [Indexed: 10/19/2023]
Affiliation(s)
- Koenraad H Nieboer
- Department of Radiology and Medical Imaging, Vrije Universiteit Brussel (VUB), Universitair Ziekenhuis Brussel, Laarbeeklaan 101, 1090, Brussels, Belgium.
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37
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Ham AS, Hacker CT, Guo J, Sorby-Adams A, Kimberly WT, Mateen FJ. Feasibility and tolerability of portable, low-field brain MRI for patients with multiple sclerosis. Mult Scler Relat Disord 2024; 85:105515. [PMID: 38489947 DOI: 10.1016/j.msard.2024.105515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 01/22/2024] [Accepted: 02/24/2024] [Indexed: 03/17/2024]
Abstract
Low-field, portable MRI (LF-MRI) promises to expand neuroimaging access for patients with multiple sclerosis (MS). We aimed to measure the feasibility and tolerability of LF-MRI for clinical use in 50 people with MS (mean age 46.5 ± 15.3 years; 72 % female; median disease duration 5.9 years), 38 % of whom reported barriers to undergoing MRI, and 34 % of whom were low-income or unemployed. Experience ratings of LF-MRI were strongly positive (mean rating of 9.2 on a ten-point scale). Seventy percent of participants were willing to receive future LF-MRI scans, and 46 % preferred LF-MRI to standard MRI (35 % undecided). The overall feasibility and tolerability of LF-MRI support its integration into a one-stop, patient-centered model of outpatient MS care.
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Affiliation(s)
- Andrew Siyoon Ham
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
| | | | - Jennifer Guo
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA; Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Annabel Sorby-Adams
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA; Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - W Taylor Kimberly
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA; Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Farrah J Mateen
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA.
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38
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Shen S, Koonjoo N, Longarino FK, Lamb LR, Villa Camacho JC, Hornung TPP, Ogier SE, Yan S, Bortfeld TR, Saksena MA, Keenan KE, Rosen MS. Breast imaging with an ultra-low field MRI scanner: a pilot study. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.04.01.24305081. [PMID: 38633799 PMCID: PMC11023648 DOI: 10.1101/2024.04.01.24305081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/19/2024]
Abstract
Breast cancer screening is necessary to reduce mortality due to undetected breast cancer. Current methods have limitations, and as a result many women forego regular screening. Magnetic resonance imaging (MRI) can overcome most of these limitations, but access to conventional MRI is not widely available for routine annual screening. Here, we used an MRI scanner operating at ultra-low field (ULF) to image the left breasts of 11 women (mean age, 35 years ±13 years) in the prone position. Three breast radiologists reviewed the imaging and were able to discern the breast outline and distinguish fibroglandular tissue (FGT) from intramammary adipose tissue. Additionally, the expert readers agreed on their assessment of the breast tissue pattern including fatty, scattered FGT, heterogeneous FGT, and extreme FGT. This preliminary work demonstrates that ULF breast MRI is feasible and may be a potential option for comfortable, widely deployable, and low-cost breast cancer diagnosis and screening.
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Xuan L, Zhang Y, Wu J, He Y, Xu Z. Quantitative brain mapping using magnetic resonance fingerprinting on a 50-mT portable MRI scanner. NMR IN BIOMEDICINE 2024; 37:e5077. [PMID: 38057971 DOI: 10.1002/nbm.5077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 10/17/2023] [Accepted: 11/02/2023] [Indexed: 12/08/2023]
Abstract
Ultralow-field magnetic resonance imaging (ULF-MRI) has broad application prospects because of its portable hardware system and low cost. However, the low B0 magnitude of ULF-MRI results in a reduced signal-to-noise ratio in qualitative images compared with that of commercial high-field MRI, which can affect the visibility and delineation of tissues and lesions. In this work, a magnetic resonance fingerprinting (MRF) approach is applied to a homemade 50-mT ULF-MRI scanner to achieve efficient quantitative brain imaging, which is an original and promising disease-diagnosis approach for portable MRI systems. An inversion recovery fast imaging with steady-state precession-based sequence is utilized for MRF through Cartesian acquisition. A microdictionary analysis method is proposed to select the optimal repetition time and flip angle variation schedule and ensure the best possible tissue discriminative ability of MRF. The T1 and T2 relaxation properties and the B1 + distribution are considered for estimation, and the results are compared with those of gold standard (GS) quantitative imaging or qualitative imaging methods. The phantom experiment indicates that the quantitative values obtained by schedule-optimized MRF show good agreement, and the bias from the GS results is acceptable. The in vivo experiment shows that the relaxation times of white and gray matter estimated by MRF are slightly lower than the reference data, and the relaxation times of lipid are within the range of the reference data. Compared with qualitative MRI under ULF, MRF can intuitively reflect various items of brain tissue information in a single scan, so it is a valuable addition to point-of-care imaging approaches.
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Affiliation(s)
- Liang Xuan
- School of Electrical Engineering, Chongqing University, Chongqing, China
| | - Yuxiang Zhang
- School of Electrical Engineering, Chongqing University, Chongqing, China
| | - Jiamin Wu
- Shenzhen Academy of Aerospace Technology, Shenzhen, China
| | - Yucheng He
- Shenzhen Academy of Aerospace Technology, Shenzhen, China
| | - Zheng Xu
- School of Electrical Engineering, Chongqing University, Chongqing, China
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40
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Cho SM, Khanduja S, Kim J, Kang JK, Briscoe J, Arlinghaus LR, Dinh K, Kim BS, Sair HI, Wandji ACN, Moreno E, Torres G, Gavito-Higuera J, Choi HA, Pitts J, Gusdon AM, Whitman GJ. Detection of Acute Brain Injury in Intensive Care Unit Patients on ECMO Support Using Ultra-Low-Field Portable MRI: A Retrospective Analysis Compared to Head CT. Diagnostics (Basel) 2024; 14:606. [PMID: 38535027 PMCID: PMC10968816 DOI: 10.3390/diagnostics14060606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 03/04/2024] [Accepted: 03/09/2024] [Indexed: 09/05/2024] Open
Abstract
Early detection of acute brain injury (ABI) is critical to intensive care unit (ICU) patient management and intervention to decrease major complications. Head CT (HCT) is the standard of care for the assessment of ABI in ICU patients; however, it has limited sensitivity compared to MRI. We retrospectively compared the ability of ultra-low-field portable MR (ULF-pMR) and head HCT, acquired within 24 h of each other, to detect ABI in ICU patients supported on extracorporeal membrane oxygenation (ECMO). A total of 17 adult patients (median age 55 years; 47% male) were included in the analysis. Of the 17 patients assessed, ABI was not observed on either ULF-pMR or HCT in eight patients (47%). ABI was observed in the remaining nine patients with a total of 10 events (8 ischemic, 2 hemorrhagic). Of the eight ischemic events, ULF-pMR observed all eight, while HCT only observed four events. Regarding hemorrhagic stroke, ULF-pMR observed only one of them, while HCT observed both. ULF-pMR outperformed HCT for the detection of ABI, especially ischemic injury, and may offer diagnostic advantages for ICU patients. The lack of sensitivity to hemorrhage may improve with modification of the imaging acquisition program.
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Affiliation(s)
- Sung-Min Cho
- Division of Cardiac Surgery, Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Division of Neuroscience Critical Care, Departments of Neurosurgery, Anesthesiology, Critical Care Medicine, The Johns Hopkins Hospital, Baltimore, MD 21287, USA
| | - Shivalika Khanduja
- Division of Cardiac Surgery, Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Jiah Kim
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jin Kook Kang
- Division of Cardiac Surgery, Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Jessica Briscoe
- Division of Cardiac Surgery, Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | | | - Kha Dinh
- Divisions of Pulmonary, Critical Care and Sleep Medicine, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
- Department of Advanced Cardiopulmonary Therapies and Transplantation, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Bo Soo Kim
- Division of Cardiac Surgery, Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins Medicine, Baltimore, MD 21205, USA
| | - Haris I Sair
- Division of Neuroradiology, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
- The Malone Center for Engineering in Healthcare, The Whiting School of Engineering, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Audrey-Carelle N Wandji
- Division of Neurocritical Care, Department of Neurosurgery, McGovern School of Medicine, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Elena Moreno
- Division of Neurocritical Care, Department of Neurosurgery, McGovern School of Medicine, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Glenda Torres
- Division of Neurocritical Care, Department of Neurosurgery, McGovern School of Medicine, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Jose Gavito-Higuera
- Department of Diagnostic and Interventional Imaging, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Huimahn A Choi
- Division of Neurocritical Care, Department of Neurosurgery, McGovern School of Medicine, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - John Pitts
- Hyperfine, Inc., Guilford, CT 06437, USA
| | - Aaron M Gusdon
- Division of Neurocritical Care, Department of Neurosurgery, McGovern School of Medicine, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Glenn J Whitman
- Division of Cardiac Surgery, Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
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Meng F, Guo Y, Wei H, Xu Z. Development of a Helmet-Shape Dual-Channel RF coil for brain imaging at 54 mT using inverse boundary element method. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2024; 360:107636. [PMID: 38377783 DOI: 10.1016/j.jmr.2024.107636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 02/04/2024] [Accepted: 02/08/2024] [Indexed: 02/22/2024]
Abstract
Very-low field (VLF) magnetic resonance imaging (MRI) offers advantages in term of size, weight, cost, and the absence of robust shielding requirements. However, it encounters challenges in maintaining a high signal-to-noise ratio (SNR) due to low magnetic fields (below 100 mT). Developing a close-fitting radio frequency (RF) receive coil is crucial to improve the SNR. In this study, we devised and optimized a helmet-shaped dual-channel RF receive coil tailored for brain imaging at a magnetic field strength of 54 mT (2.32 MHz). The methodology integrates the inverse boundary element method (IBEM) to formulate initial coil structures and wiring patterns, followed by optimization through introducing regularization terms. This approach frames the design process as an inverse problem, ensuring a close fit to the head contour. Combining theoretical optimization with physical measurements of the coil's AC resistance, we identified the optimal loop count for both axial and radial coils as nine and eight loops, respectively. The effectiveness of the designed dual-channel coil was verified through the imaging of a CuSO4 phantom and a healthy volunteer's brain. Notably, the in-vivo images exhibited an approximate 16-25 % increase in SNR with poorer B1 homogeneity compared to those obtained using single-channel coils. The high-quality images achieved by T1, T2-weighted, and fluid-attenuated inversion-recovery (FLAIR) protocols enhance the diagnostic potential of VLF MRI, particularly in cases of cerebral stroke and trauma patients. This study underscores the adaptability of the design methodology for the customization of RF coil structures in alignment with individual imaging requirements.
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Affiliation(s)
- Fanqin Meng
- School of Electrical Engineering, Chongqing University, Chongqing 400044, China
| | - Yi Guo
- Central Hospital, Chongqing University, Chongqing 400014, China
| | - He Wei
- School of Electrical Engineering, Chongqing University, Chongqing 400044, China
| | - Zheng Xu
- School of Electrical Engineering, Chongqing University, Chongqing 400044, China.
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Cooper R, Hayes RA, Corcoran M, Sheth KN, Arnold TC, Stein JM, Glahn DC, Jalbrzikowski M. Bridging the gap: improving correspondence between low-field and high-field magnetic resonance images in young people. Front Neurol 2024; 15:1339223. [PMID: 38585353 PMCID: PMC10995930 DOI: 10.3389/fneur.2024.1339223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Accepted: 01/19/2024] [Indexed: 04/09/2024] Open
Abstract
Background Portable low-field-strength magnetic resonance imaging (MRI) systems represent a promising alternative to traditional high-field-strength systems with the potential to make MR technology available at scale in low-resource settings. However, lower image quality and resolution may limit the research and clinical potential of these devices. We tested two super-resolution methods to enhance image quality in a low-field MR system and compared their correspondence with images acquired from a high-field system in a sample of young people. Methods T1- and T2-weighted structural MR images were obtained from a low-field (64mT) Hyperfine and high-field (3T) Siemens system in N = 70 individuals (mean age = 20.39 years, range 9-26 years). We tested two super-resolution approaches to improve image correspondence between images acquired at high- and low-field: (1) processing via a convolutional neural network ('SynthSR'), and (2) multi-orientation image averaging. We extracted brain region volumes, cortical thickness, and cortical surface area estimates. We used Pearson correlations to test the correspondence between these measures, and Steiger Z tests to compare the difference in correspondence between standard imaging and super-resolution approaches. Results Single pairs of T1- and T2-weighted images acquired at low field showed high correspondence to high-field-strength images for estimates of total intracranial volume, surface area cortical volume, subcortical volume, and total brain volume (r range = 0.60-0.88). Correspondence was lower for cerebral white matter volume (r = 0.32, p = 0.007, q = 0.009) and non-significant for mean cortical thickness (r = -0.05, p = 0.664, q = 0.664). Processing images with SynthSR yielded significant improvements in correspondence for total brain volume, white matter volume, total surface area, subcortical volume, cortical volume, and total intracranial volume (r range = 0.85-0.97), with the exception of global mean cortical thickness (r = 0.14). An alternative multi-orientation image averaging approach improved correspondence for cerebral white matter and total brain volume. Processing with SynthSR also significantly improved correspondence across widespread regions for estimates of cortical volume, surface area and subcortical volume, as well as within isolated prefrontal and temporal regions for estimates of cortical thickness. Conclusion Applying super-resolution approaches to low-field imaging improves regional brain volume and surface area accuracy in young people. Finer-scale brain measurements, such as cortical thickness, remain challenging with the limited resolution of low-field systems.
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Affiliation(s)
- Rebecca Cooper
- Department of Psychiatry and Behavioral Sciences, Boston Children’s Hospital, Boston, MA, United States
- Department of Psychiatry, Harvard Medical School, Boston, MA, United States
| | - Rebecca A. Hayes
- Department of Psychiatry and Behavioral Sciences, Boston Children’s Hospital, Boston, MA, United States
| | - Mary Corcoran
- Department of Psychiatry and Behavioral Sciences, Boston Children’s Hospital, Boston, MA, United States
| | - Kevin N. Sheth
- Center for Brain and Mind Health, Yale School of Medicine, New Haven, CT, United States
| | - Thomas Campbell Arnold
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA, United States
| | - Joel M. Stein
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA, United States
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - David C. Glahn
- Department of Psychiatry and Behavioral Sciences, Boston Children’s Hospital, Boston, MA, United States
- Department of Psychiatry, Harvard Medical School, Boston, MA, United States
- Olin Neuropsychiatry Research Center, Institute of Living, Hartford, CT, United States
| | - Maria Jalbrzikowski
- Department of Psychiatry and Behavioral Sciences, Boston Children’s Hospital, Boston, MA, United States
- Department of Psychiatry, Harvard Medical School, Boston, MA, United States
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43
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Tarui T, Gimovsky AC, Madan N. Fetal neuroimaging applications for diagnosis and counseling of brain anomalies: Current practice and future diagnostic strategies. Semin Fetal Neonatal Med 2024; 29:101525. [PMID: 38632010 PMCID: PMC11156536 DOI: 10.1016/j.siny.2024.101525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2024]
Abstract
Advances in fetal brain neuroimaging, especially fetal neurosonography and brain magnetic resonance imaging (MRI), allow safe and accurate anatomical assessments of fetal brain structures that serve as a foundation for prenatal diagnosis and counseling regarding fetal brain anomalies. Fetal neurosonography strategically assesses fetal brain anomalies suspected by screening ultrasound. Fetal brain MRI has unique technological features that overcome the anatomical limits of smaller fetal brain size and the unpredictable variable of intrauterine motion artifact. Recent studies of fetal brain MRI provide evidence of improved diagnostic and prognostic accuracy, beginning with prenatal diagnosis. Despite technological advances over the last several decades, the combined use of different qualitative structural biomarkers has limitations in providing an accurate prognosis. Quantitative analyses of fetal brain MRIs offer measurable imaging biomarkers that will more accurately associate with clinical outcomes. First-trimester ultrasound opens new opportunities for risk assessment and fetal brain anomaly diagnosis at the earliest time in pregnancy. This review includes a case vignette to illustrate how fetal brain MRI results interpreted by the fetal neurologist can improve diagnostic perspectives. The strength and limitations of conventional ultrasound and fetal brain MRI will be compared with recent research advances in quantitative methods to better correlate fetal neuroimaging biomarkers of neuropathology to predict functional childhood deficits. Discussion of these fetal sonogram and brain MRI advances will highlight the need for further interdisciplinary collaboration using complementary skills to continue improving clinical decision-making following precision medicine principles.
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Affiliation(s)
- Tomo Tarui
- Pediatric Neurology, Pediatrics, Hasbro Children's Hospital, The Warren Alpert Medical School of Brown University, Providence, RI, USA.
| | - Alexis C Gimovsky
- Maternal Fetal Medicine, Obstetrics and Gynecology, Women & Infants Hospital of Rhode Island, The Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Neel Madan
- Neuroradiology, Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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44
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Foschi M, Galante A, Ornello R, Necozione S, Marini C, Muselli M, Achard PO, Fratocchi L, Vinci SL, Cavallaro M, Silvestrini M, Polonara G, Marcheselli S, Straffi L, Colasurdo M, Sorrentino L, Franconi E, Alecci M, Caulo M, Sacco S. Point-Of-Care low-field MRI in acute Stroke (POCS): protocol for a multicentric prospective open-label study evaluating diagnostic accuracy. BMJ Open 2024; 14:e075614. [PMID: 38296269 PMCID: PMC10831427 DOI: 10.1136/bmjopen-2023-075614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Accepted: 01/16/2024] [Indexed: 02/03/2024] Open
Abstract
INTRODUCTION Fast and accurate diagnosis of acute stroke is crucial to timely initiate reperfusion therapies. Conventional high-field (HF) MRI yields the highest accuracy in discriminating early ischaemia from haemorrhages and mimics. Rapid access to HF-MRI is often limited by contraindications or unavailability. Low-field (LF) MRI (<0.5T) can detect several types of brain injury, including ischaemic and haemorrhagic stroke. Implementing LF-MRI in acute stroke care may offer several advantages, including extended applicability, increased safety, faster administration, reduced staffing and costs. This multicentric prospective open-label trial aims to evaluate the diagnostic accuracy of LF-MRI, as a tool to guide treatment decision in acute stroke. METHODS AND ANALYSIS Consecutive patients accessing the emergency department with suspected stroke dispatch will be recruited at three Italian study units: Azienda Sanitaria Locale (ASL) Abruzzo 1 and 2, Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Humanitas Research Hospital. The estimated sample size is 300 patients. Anonymised clinical and LF-MRI data, along with conventional neuroimaging data, will be independently assessed by two external units: Marche Polytechnic University and 'G. Martino' Polyclinic University Hospital. Both units will independently adjudicate the best treatment option, while the latter will provide historical HF-MRI data to develop artificial intelligence algorithms for LF-MRI images interpretation (Free University of Bozen-Bolzano). Agreement with conventional neuroimaging will be evaluated at different time points: hyperacute, acute (24 hours), subacute (72 hours), at discharge and chronic (4 weeks). Further investigations will include feasibility study to develop a mobile stroke unit equipped with LF-MRI and cost-effectiveness analysis. This trial will provide necessary data to validate the use of LF-MRI in acute stroke care. ETHICS AND DISSEMINATION The study was approved by the Research Ethics Committee of the Abruzzo Region (CEtRA) on 11 May 2023 (approval code: richyvgrg). Results will be disseminated in peer-reviewed journals and presented in academic conferences. TRIAL REGISTRATION NUMBER NCT05816213; Pre-Results.
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Affiliation(s)
- Matteo Foschi
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, L'Aquila, Italy
| | - Angelo Galante
- Department of Life, Health & Environmental Sciences, University of L'Aquila, L'Aquila, Italy
- National Institute for Nuclear Physics, Gran Sasso National Laboratory, L'Aquila, Italy
- SPIN-CNR, c/o Department of Physical and Chemical Science, University of L'Aquila, L'Aquila, Italy
| | - Raffaele Ornello
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, L'Aquila, Italy
| | - Stefano Necozione
- Department of Life, Health & Environmental Sciences, University of L'Aquila, L'Aquila, Italy
| | - Carmine Marini
- Department of Life, Health & Environmental Sciences, University of L'Aquila, L'Aquila, Italy
| | - Mario Muselli
- Department of Life, Health & Environmental Sciences, University of L'Aquila, L'Aquila, Italy
| | - Paola Olimpia Achard
- Department of Industrial and Information Engineering and Economics, University of L'Aquila, L'Aquila, Italy
| | - Luciano Fratocchi
- Department of Industrial and Information Engineering and Economics, University of L'Aquila, L'Aquila, Italy
| | - Sergio Lucio Vinci
- Department of Biomorf, University of Messina, UOC Neuroradiology, Messina, Italy
| | - Marco Cavallaro
- Department of Biomorf, University of Messina, UOC Neuroradiology, Messina, Italy
| | - Mauro Silvestrini
- Department of Experimental and Clinical Medicine, Neurological Clinic, Marche Polytechnic University, Ancona, Italy
| | - Gabriele Polonara
- Department of Odontostomatological and Specialized Clinical Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Simona Marcheselli
- Emergency Neurology and Stroke Unit, IRCCS Humanitas Research Hospital, Rozzano, Italy
| | - Laura Straffi
- Emergency Neurology and Stroke Unit, IRCCS Humanitas Research Hospital, Rozzano, Italy
| | - Marco Colasurdo
- Department of Neuroscience and Clinical Sciences, University of Chieti, Chieti, Italy
| | - Luca Sorrentino
- Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino, Italy
| | - Enrico Franconi
- Faculty of Computer Science, Free University of Bozen-Bolzano, Bolzano, Italy
| | - Marcello Alecci
- Department of Life, Health & Environmental Sciences, University of L'Aquila, L'Aquila, Italy
- National Institute for Nuclear Physics, Gran Sasso National Laboratory, L'Aquila, Italy
- SPIN-CNR, c/o Department of Physical and Chemical Science, University of L'Aquila, L'Aquila, Italy
| | - Massimo Caulo
- Department of Neuroscience and Clinical Sciences, University of Chieti, Chieti, Italy
| | - Simona Sacco
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, L'Aquila, Italy
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45
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Cho SM, Khanduja S, Wilcox C, Dinh K, Kim J, Kang JK, Chinedozi ID, Darby Z, Acton M, Rando H, Briscoe J, Bush E, Sair HI, Pitts J, Arlinghaus LR, Wandji ACN, Moreno E, Torres G, Akkanti B, Gavito-Higuera J, Keller S, Choi HA, Kim BS, Gusdon A, Whitman GJ. Clinical Use of Bedside Portable Low-field Brain Magnetic Resonance Imaging in Patients on ECMO: The Results from Multicenter SAFE MRI ECMO Study. RESEARCH SQUARE 2024:rs.3.rs-3858221. [PMID: 38313271 PMCID: PMC10836091 DOI: 10.21203/rs.3.rs-3858221/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2024]
Abstract
Purpose Early detection of acute brain injury (ABI) is critical for improving survival for patients with extracorporeal membrane oxygenation (ECMO) support. We aimed to evaluate the safety of ultra-low-field portable MRI (ULF-pMRI) and the frequency and types of ABI observed during ECMO support. Methods We conducted a multicenter prospective observational study (NCT05469139) at two academic tertiary centers (August 2022-November 2023). Primary outcomes were safety and validation of ULF-pMRI in ECMO, defined as exam completion without adverse events (AEs); secondary outcomes were ABI frequency and type. Results ULF-pMRI was performed in 50 patients with 34 (68%) on venoarterial (VA)-ECMO (11 central; 23 peripheral) and 16 (32%) with venovenous (VV)-ECMO (9 single lumen; 7 double lumen). All patients were imaged successfully with ULF-pMRI, demonstrating discernible intracranial pathologies with good quality. AEs occurred in 3 (6%) patients (2 minor; 1 serious) without causing significant clinical issues.ABI was observed in ULF-pMRI scans for 22 patients (44%): ischemic stroke (36%), intracranial hemorrhage (6%), and hypoxic-ischemic brain injury (4%). Of 18 patients with both ULF-pMRI and head CT (HCT) within 24 hours, ABI was observed in 9 patients with 10 events: 8 ischemic (8 observed on ULF-oMRI, 4 on HCT) and 2 hemorrhagic (1 observed on ULF-pMRI, 2 on HCT). Conclusions ULF-pMRI was shown to be safe and valid in ECMO patients across different ECMO cannulation strategies. The incidence of ABI was high, and ULF-pMRI may more sensitive to ischemic ABI than HCT. ULF-pMRI may benefit both clinical care and future studies of ECMO-associated ABI.
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Affiliation(s)
| | | | | | - Kha Dinh
- UTHSC: The University of Texas Health Science Center at Houston
| | - Jiah Kim
- Johns Hopkins Hospital: Johns Hopkins Medicine
| | | | | | | | | | | | | | - Errol Bush
- Johns Hopkins Hospital: Johns Hopkins Medicine
| | | | | | | | | | - Elena Moreno
- UTHSC: The University of Texas Health Science Center at Houston
| | - Glenda Torres
- UTHSC: The University of Texas Health Science Center at Houston
| | - Bindu Akkanti
- UTHSC: The University of Texas Health Science Center at Houston
| | | | | | - HuiMahn A Choi
- UTHSC: The University of Texas Health Science Center at Houston
| | - Bo Soo Kim
- Johns Hopkins Hospital: Johns Hopkins Medicine
| | - Aaron Gusdon
- UTHSC: The University of Texas Health Science Center at Houston
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46
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Sherman SE, Zammit AS, Heo WS, Rosen MS, Cima MJ. Single-sided magnetic resonance-based sensor for point-of-care evaluation of muscle. Nat Commun 2024; 15:440. [PMID: 38199994 PMCID: PMC10782019 DOI: 10.1038/s41467-023-44561-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 12/19/2023] [Indexed: 01/12/2024] Open
Abstract
Magnetic resonance imaging is a widespread clinical tool for the detection of soft tissue morphology and pathology. However, the clinical deployment of magnetic resonance imaging scanners is ultimately limited by size, cost, and space constraints. Here, we discuss the design and performance of a low-field single-sided magnetic resonance sensor intended for point-of-care evaluation of skeletal muscle in vivo. The 11 kg sensor has a penetration depth of >8 mm, which allows for an accurate analysis of muscle tissue and can avoid signal from more proximal layers, including subcutaneous adipose tissue. Low operational power and shielding requirements are achieved through the design of a permanent magnet array and surface transceiver coil. The sensor can acquire high signal-to-noise measurements in minutes, making it practical as a point-of-care tool for many quantitative diagnostic measurements, including T2 relaxometry. In this work, we present the in vitro and human in vivo performance of the device for muscle tissue evaluation.
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Affiliation(s)
- Sydney E Sherman
- Harvard-MIT Program in Health Science and Technology, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Alexa S Zammit
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Won-Seok Heo
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Matthew S Rosen
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, 02129, USA
- Harvard Medical School, Boston, MA, 02115, USA
- Department of Physics, Harvard University, Cambridge, MA, 02138, USA
| | - Michael J Cima
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
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47
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Jalloul M, Miranda-Schaeubinger M, Noor AM, Stein JM, Amiruddin R, Derbew HM, Mango VL, Akinola A, Hart K, Weygand J, Pollack E, Mohammed S, Scheel JR, Shell J, Dako F, Mhatre P, Kulinski L, Otero HJ, Mollura DJ. MRI scarcity in low- and middle-income countries. NMR IN BIOMEDICINE 2023; 36:e5022. [PMID: 37574441 DOI: 10.1002/nbm.5022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 07/19/2023] [Accepted: 07/21/2023] [Indexed: 08/15/2023]
Abstract
Since the introduction of MRI as a sustainable diagnostic modality, global accessibility to its services has revealed a wide discrepancy between populations-leaving most of the population in LMICs without access to this important imaging modality. Several factors lead to the scarcity of MRI in LMICs; for example, inadequate infrastructure and the absence of a dedicated workforce are key factors in the scarcity observed. RAD-AID has contributed to the advancement of radiology globally by collaborating with our partners to make radiology more accessible for medically underserved communities. However, progress is slow and further investment is needed to ensure improved global access to MRI.
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Affiliation(s)
- Mohammad Jalloul
- Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | | | - Abass M Noor
- Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- RAD-AID International, Chevy Chase, Maryland, USA
- Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Joel M Stein
- Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Raisa Amiruddin
- Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Hermon Miliard Derbew
- Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- College of Health Science, Addis Ababa University, Addis Ababa, Ethiopia
| | - Victoria L Mango
- RAD-AID International, Chevy Chase, Maryland, USA
- Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | | | - Kelly Hart
- Tufts Medical Center, Boston, Massachusetts, USA
| | | | - Erica Pollack
- RAD-AID International, Chevy Chase, Maryland, USA
- University of Colorado Anschutz Medical Center, Aurora, Colorado, USA
| | - Sharon Mohammed
- RAD-AID International, Chevy Chase, Maryland, USA
- Bellevue Hospital Center NYCHHC, New York, New York, USA
| | - John R Scheel
- RAD-AID International, Chevy Chase, Maryland, USA
- Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Jessica Shell
- RAD-AID International, Chevy Chase, Maryland, USA
- Siemens Medical Solutions USA, Inc., Cary, North Carolina, USA
| | - Farouk Dako
- RAD-AID International, Chevy Chase, Maryland, USA
- Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Pradnya Mhatre
- RAD-AID International, Chevy Chase, Maryland, USA
- Emory University School of Medicine, Atlanta, Georgia, USA
| | | | - Hansel J Otero
- Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
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48
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Islam KT, Zhong S, Zakavi P, Chen Z, Kavnoudias H, Farquharson S, Durbridge G, Barth M, McMahon KL, Parizel PM, Dwyer A, Egan GF, Law M, Chen Z. Improving portable low-field MRI image quality through image-to-image translation using paired low- and high-field images. Sci Rep 2023; 13:21183. [PMID: 38040835 PMCID: PMC10692211 DOI: 10.1038/s41598-023-48438-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 11/27/2023] [Indexed: 12/03/2023] Open
Abstract
Low-field portable magnetic resonance imaging (MRI) scanners are more accessible, cost-effective, sustainable with lower carbon emissions than superconducting high-field MRI scanners. However, the images produced have relatively poor image quality, lower signal-to-noise ratio, and limited spatial resolution. This study develops and investigates an image-to-image translation deep learning model, LoHiResGAN, to enhance the quality of low-field (64mT) MRI scans and generate synthetic high-field (3T) MRI scans. We employed a paired dataset comprising T1- and T2-weighted MRI sequences from the 64mT and 3T and compared the performance of the LoHiResGAN model with other state-of-the-art models, including GANs, CycleGAN, U-Net, and cGAN. Our proposed method demonstrates superior performance in terms of image quality metrics, such as normalized root-mean-squared error, structural similarity index measure, peak signal-to-noise ratio, and perception-based image quality evaluator. Additionally, we evaluated the accuracy of brain morphometry measurements for 33 brain regions across the original 3T, 64mT, and synthetic 3T images. The results indicate that the synthetic 3T images created using our proposed LoHiResGAN model significantly improve the image quality of low-field MRI data compared to other methods (GANs, CycleGAN, U-Net, cGAN) and provide more consistent brain morphometry measurements across various brain regions in reference to 3T. Synthetic images generated by our method demonstrated high quality both quantitatively and qualitatively. However, additional research, involving diverse datasets and clinical validation, is necessary to fully understand its applicability for clinical diagnostics, especially in settings where high-field MRI scanners are less accessible.
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Affiliation(s)
- Kh Tohidul Islam
- Monash Biomedical Imaging, Monash University, Melbourne, VIC, Australia.
| | - Shenjun Zhong
- Monash Biomedical Imaging, Monash University, Melbourne, VIC, Australia
- Australian National Imaging Facility, Brisbane, QLD, Australia
| | - Parisa Zakavi
- Monash Biomedical Imaging, Monash University, Melbourne, VIC, Australia
| | - Zhifeng Chen
- Monash Biomedical Imaging, Monash University, Melbourne, VIC, Australia
- Department of Data Science and AI, Faculty of Information Technology, Monash University, Melbourne, VIC, Australia
| | - Helen Kavnoudias
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Radiology, Alfred Hospital, Melbourne, VIC, Australia
| | | | - Gail Durbridge
- Herston Imaging Research Facility, University of Queensland, Brisbane, QLD, Australia
| | - Markus Barth
- School of Information Technology and Electrical Engineering and Centre for Advanced Imaging, University of Queensland, Brisbane, QLD, Australia
| | - Katie L McMahon
- School of Clinical Science, Herston Imaging Research Facility, Queensland University of Technology, Brisbane, QLD, Australia
| | - Paul M Parizel
- David Hartley Chair of Radiology, Department of Radiology, Royal Perth Hospital, Perth, WA, Australia
- Medical School, University of Western Australia, Perth, WA, Australia
| | - Andrew Dwyer
- South Australian Health and Medical Research Institute, Adelaide, SA, Australia
| | - Gary F Egan
- Monash Biomedical Imaging, Monash University, Melbourne, VIC, Australia
| | - Meng Law
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Radiology, Alfred Hospital, Melbourne, VIC, Australia
| | - Zhaolin Chen
- Monash Biomedical Imaging, Monash University, Melbourne, VIC, Australia
- Department of Data Science and AI, Faculty of Information Technology, Monash University, Melbourne, VIC, Australia
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49
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Samaniego EA, Boltze J, Lyden PD, Hill MD, Campbell BCV, Silva GS, Sheth KN, Fisher M, Hillis AE, Nguyen TN, Carone D, Favilla CG, Deljkich E, Albers GW, Heit JJ, Lansberg MG. Priorities for Advancements in Neuroimaging in the Diagnostic Workup of Acute Stroke. Stroke 2023; 54:3190-3201. [PMID: 37942645 PMCID: PMC10841844 DOI: 10.1161/strokeaha.123.044985] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Accepted: 10/03/2023] [Indexed: 11/10/2023]
Abstract
STAIR XII (12th Stroke Treatment Academy Industry Roundtable) included a workshop to discuss the priorities for advancements in neuroimaging in the diagnostic workup of acute ischemic stroke. The workshop brought together representatives from academia, industry, and government. The participants identified 10 critical areas of priority for the advancement of acute stroke imaging. These include enhancing imaging capabilities at primary and comprehensive stroke centers, refining the analysis and characterization of clots, establishing imaging criteria that can predict the response to reperfusion, optimizing the Thrombolysis in Cerebral Infarction scale, predicting first-pass reperfusion outcomes, improving imaging techniques post-reperfusion therapy, detecting early ischemia on noncontrast computed tomography, enhancing cone beam computed tomography, advancing mobile stroke units, and leveraging high-resolution vessel wall imaging to gain deeper insights into pathology. Imaging in acute ischemic stroke treatment has advanced significantly, but important challenges remain that need to be addressed. A combined effort from academic investigators, industry, and regulators is needed to improve imaging technologies and, ultimately, patient outcomes.
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Affiliation(s)
- Edgar A. Samaniego
- Department of Neurology, Radiology and Neurosurgery, University of Iowa Carver College of Medicine, Iowa City, Iowa, United States
| | - Johannes Boltze
- School of Life Sciences, The University of Warwick, Coventry, United Kingdom
| | - Patrick D. Lyden
- Zilkha Neurogenetic Institute of the Keck School of Medicine at USC, Los Angeles, California, United States
| | - Michael D. Hill
- Department of Clinical Neuroscience & Hotchkiss Brain Institute, University of Calgary & Foothills Medical Centre, Calgary, Canada
| | - Bruce CV Campbell
- Department of Medicine and Neurology, Royal Melbourne Hospital, University of Melbourne, Parkville, Victoria, Australia
| | - Gisele Sampaio Silva
- Department of Neurology and Neurosurgery, Federal University of São Paulo, São Paulo, Brazil
| | - Kevin N Sheth
- Department of Neurology, Division of Neurocritical Care and Emergency Neurology, Yale School of Medicine, New Haven, United States
| | - Marc Fisher
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States
| | - Argye E. Hillis
- Department of Neurology, School of Medicine, Johns Hopkins University, Baltimore, Maryland, United Stated
| | - Thanh N. Nguyen
- Department of Neurology, Boston Medical Center, Massachusetts, United States
| | - Davide Carone
- Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Christopher G. Favilla
- Department of Neurology, University of Pennsylvania Philadelphia, Pennsylvania, Unites States
| | | | - Gregory W. Albers
- Department of Neurology, Stanford University, Stanford, California, United States
| | - Jeremy J. Heit
- Department of Radiology and Neurosurgery, Stanford University, Stanford, California, United States
| | - Maarten G Lansberg
- Department of Neurology, Stanford University, Stanford, California, United States
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50
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Johnson PM, Lui YW. The deep route to low-field MRI with high potential. Nature 2023; 623:700-701. [PMID: 37964114 DOI: 10.1038/d41586-023-03531-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2023]
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