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Ebrahimi S, Lundström E, Batasin SJ, Hedlund E, Stålberg K, Ehman EC, Sheth VR, Iranpour N, Loubrie S, Schlein A, Rakow-Penner R. Application of PET/MRI in Gynecologic Malignancies. Cancers (Basel) 2024; 16:1478. [PMID: 38672560 PMCID: PMC11048306 DOI: 10.3390/cancers16081478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2024] [Revised: 03/23/2024] [Accepted: 03/27/2024] [Indexed: 04/28/2024] Open
Abstract
The diagnosis, treatment, and management of gynecologic malignancies benefit from both positron emission tomography/computed tomography (PET/CT) and MRI. PET/CT provides important information on the local extent of disease as well as diffuse metastatic involvement. MRI offers soft tissue delineation and loco-regional disease involvement. The combination of these two technologies is key in diagnosis, treatment planning, and evaluating treatment response in gynecological malignancies. This review aims to assess the performance of PET/MRI in gynecologic cancer patients and outlines the technical challenges and clinical advantages of PET/MR systems when specifically applied to gynecologic malignancies.
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Affiliation(s)
- Sheida Ebrahimi
- Department of Radiology, University of California San Diego, La Jolla, CA 92093, USA
| | - Elin Lundström
- Department of Radiology, University of California San Diego, La Jolla, CA 92093, USA
- Department of Surgical Sciences, Radiology, Uppsala University, 751 85 Uppsala, Sweden
- Center for Medical Imaging, Uppsala University Hospital, 751 85 Uppsala, Sweden
| | - Summer J. Batasin
- Department of Radiology, University of California San Diego, La Jolla, CA 92093, USA
| | - Elisabeth Hedlund
- Department of Surgical Sciences, Radiology, Uppsala University, 751 85 Uppsala, Sweden
| | - Karin Stålberg
- Department of Women’s and Children’s Health, Uppsala University, 751 85 Uppsala, Sweden
| | - Eric C. Ehman
- Department of Radiology, Mayo Clinic, Rochester, MN 55905, USA
| | - Vipul R. Sheth
- Department of Radiology, Stanford University, Palo Alto, CA 94305, USA; (V.R.S.)
| | - Negaur Iranpour
- Department of Radiology, Stanford University, Palo Alto, CA 94305, USA; (V.R.S.)
| | - Stephane Loubrie
- Department of Radiology, University of California San Diego, La Jolla, CA 92093, USA
| | - Alexandra Schlein
- Department of Radiology, University of California San Diego, La Jolla, CA 92093, USA
| | - Rebecca Rakow-Penner
- Department of Radiology, University of California San Diego, La Jolla, CA 92093, USA
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA
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Prakken NHJ, Besson FL, Borra RJH, Büther F, Buechel RR, Catana C, Chiti A, Dierckx RAJO, Dweck MR, Erba PA, Glaudemans AWJM, Gormsen LC, Hristova I, Koole M, Kwee TC, Mottaghy FM, Polycarpou I, Prokop M, Stegger L, Tsoumpas C, Slart RHJA. PET/MRI in practice: a clinical centre survey endorsed by the European Association of Nuclear Medicine (EANM) and the EANM Forschungs GmbH (EARL). Eur J Nucl Med Mol Imaging 2023; 50:2927-2934. [PMID: 37378857 DOI: 10.1007/s00259-023-06308-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/29/2023]
Affiliation(s)
- Niek H J Prakken
- Medical Imaging Centre, Departments of Nuclear Medicine and Molecular Imaging, Radiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Florent L Besson
- Commissariat À L'énergie Atomique Et Aux Énergies Alternatives (CEA), Centre National de La Recherche Scientifique (CNRS), InsermBioMaps, Orsay, France
- Department of Nuclear Medicine-Molecular Imaging, Hôpitaux Universitaires Paris-Saclay, Assistance Publique-Hôpitaux de Paris, Le Kremlin-Bicêtre, France
- School of Medicine, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Ronald J H Borra
- Medical Imaging Centre, Departments of Nuclear Medicine and Molecular Imaging, Radiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Florian Büther
- Department of Nuclear Medicine, University Hospital Münster, Munster, Germany
| | - Ronny R Buechel
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Zurich, Switzerland
| | - Ciprian Catana
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and , Harvard Medical School, Boston, MA, USA
| | - Arturo Chiti
- Department of Nuclear Medicine, IRCCS San Raffaele Scientific Institute, Milan, Italy
- Vita-Salute San Raffaele University, Milan, Italy
| | - Rudi A J O Dierckx
- Medical Imaging Centre, Departments of Nuclear Medicine and Molecular Imaging, Radiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Marc R Dweck
- British Heart Foundation Centre for Cardiovascular Science, Edinburgh Heart Centre, University of Edinburgh, Chancellors Building, Little France Crescent, Edinburgh, UK
| | - Paola A Erba
- Medical Imaging Centre, Departments of Nuclear Medicine and Molecular Imaging, Radiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
- Department of Medicine and Surgery, University of Milan Bicocca, and Nuclear Medicine Unit ASST Ospedale Papa Giovanni XXIII, Bergamo, Italy
| | - Andor W J M Glaudemans
- Medical Imaging Centre, Departments of Nuclear Medicine and Molecular Imaging, Radiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Lars C Gormsen
- Department of Nuclear Medicine & PET Centre, Aarhus University Hospital, Aarhus N, Denmark
| | - Ivalina Hristova
- European Association of Nuclear Medicine Research Ltd. (EARL), Vienna, Austria
| | - Michel Koole
- Department of Imaging and Pathology, Nuclear Medicine and Molecular Imaging, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Thomas C Kwee
- Medical Imaging Centre, Departments of Nuclear Medicine and Molecular Imaging, Radiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Felix M Mottaghy
- Department of Nuclear Medicine, University Hospital Aachen, RWTH Aachen University, Aachen, Germany
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, MUMC+), Maastricht, The Netherlands
| | - Irene Polycarpou
- Department of Health Sciences, European University Cyprus, Nicosia, Cyprus
| | - Mathias Prokop
- Medical Imaging Centre, Departments of Nuclear Medicine and Molecular Imaging, Radiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Lars Stegger
- Department of Nuclear Medicine, University Hospital Münster, Munster, Germany
| | - Charalampos Tsoumpas
- Medical Imaging Centre, Departments of Nuclear Medicine and Molecular Imaging, Radiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Riemer H J A Slart
- Medical Imaging Centre, Departments of Nuclear Medicine and Molecular Imaging, Radiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
- Biomedical Photonic Imaging Group, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands.
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Mukherjee S, Fischbein NJ, Baugnon KL, Policeni BA, Raghavan P. Contemporary Imaging and Reporting Strategies for Head and Neck Cancer: MRI, FDG PET/MRI, NI-RADS, and Carcinoma of Unknown Primary-AJR Expert Panel Narrative Review. AJR Am J Roentgenol 2023; 220:160-72. [PMID: 36069482 DOI: 10.2214/AJR.22.28120] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
CT, MRI, and FDG PET/CT play major roles in the diagnosis, staging, treatment planning, and surveillance of head and neck cancers. Nonetheless, an evolving understanding of head and neck cancer pathogenesis, advances in imaging techniques, changing treatment regimens, and a lack of standardized guidelines have led to areas of uncertainty in the imaging of head and neck cancer. This narrative review aims to address four issues in the contemporary imaging of head and neck cancer. The first issue relates to the standard and advanced sequences that should be included in MRI protocols for head and neck cancer imaging. The second issue relates to approaches to surveillance imaging after treatment of head and neck cancer, including the choice of imaging modality, the frequency of surveillance imaging, and the role of standardized reporting through the Neck Imaging Reporting and Data System. The third issue relates to the role of imaging in the setting of neck carcinoma of unknown primary. The fourth issue relates to the role of simultaneous PET/MRI in head and neck cancer evaluation. The authors of this review provide consensus opinions for each issue.
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Nakajima S, Fushimi Y, Hinoda T, Sakata A, Okuchi S, Arakawa Y, Ishimori T, Nakamoto Y. Brain imaging of sequential acquisition using a flexible PET scanner and 3-T MRI: quantitative and qualitative assessment. Ann Nucl Med 2022; 37:209-218. [PMID: 36585566 DOI: 10.1007/s12149-022-01817-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 12/23/2022] [Indexed: 01/01/2023]
Abstract
OBJECTIVE A mobile PET scanner termed flexible PET (fxPET) has been designed to fit existing MRI systems. The purpose of this study was to assess brain imaging with fxPET combined with 3-T MRI in comparison with conventional PET (cPET)/CT. METHODS In this prospective study, 29 subjects with no visible lesions except for mild leukoaraiosis on whole brain imaging underwent 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) cPET/CT followed by fxPET and MRI. The registration differences between fxPET and MRI and between cPET and CT were compared by measuring spatial coordinates. Three-dimensional magnetization-prepared rapid acquisition gradient-echo T1-weighted imaging (T1WI) was acquired. We applied two methods of attenuation correction to the fxPET images: MR-based attenuation correction, which yielded fxPETMRAC; and CT-based attenuation correction, which yielded fxPETCTAC. The three PET datasets were co-registered to the T1WI. Following subcortical segmentation and cortical parcellation, volumes of interest were placed in each PET image to assess physiological accumulation in the brain. SUVmean was obtained and compared between the three datasets. We also visually evaluated image distortion and clarity of fxPETMRAC. RESULTS Mean misregistration of fxPET/MRI was < 3 mm for each margin. Mean registration differences were significantly larger for fxPET/MRI than for cPET/CT except for the superior margin. There were high correlations between the three PET datasets regarding SUVmean. On visual evaluation of image quality, the grade of distortion was comparable between fxPETMRAC and cPET, and the grade of clarity was acceptable but inferior for fxPETMRAC compared with cPET. CONCLUSIONS fxPET could successfully determine physiological [18F]FDG uptake; however, improved image clarity is desirable. In this study, fxPET/MRI at 3-T was feasible for brain imaging.
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Affiliation(s)
- Satoshi Nakajima
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Yasutaka Fushimi
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan.
| | - Takuya Hinoda
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Akihiko Sakata
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Sachi Okuchi
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Yoshiki Arakawa
- Department of Neurosurgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Takayoshi Ishimori
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Yuji Nakamoto
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
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Disselhorst JA, Newport DF, Schmid AM, Schmidt FP, Parl C, Liu CC, Pichler BJ, Mannheim JG. NEMA NU 4-2008 performance evaluation and MR compatibility tests of an APD-based small animal PET-insert for simultaneous PET/MR imaging. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac499d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 01/10/2022] [Indexed: 11/11/2022]
Abstract
Abstract
An avalanche photodiode (APD)-based small animal positron emission tomography (PET)-insert was fully evaluated for its PET performance, as well as potential influences on magnetic resonance imaging (MRI) performance. This PET-insert has an extended axial field of view (FOV) compared with the previous design to increase system sensitivity, as well as an updated cooling and temperature regulation to enable stable and reproducible PET acquisitions. The PET performance was evaluated according to the National Electrical Manufacturers Association NU4-2008 protocol. The energy and timing resolution’s full width at half maximum were 16.1% and 4.7 ns, respectively. The reconstructed radial spatial resolution of the PET-insert was 1.8 mm full width at half maximum at the center FOV using filtered back projection for reconstruction and sensitivity was 3.68%. The peak noise equivalent count rates were 70 kcps for a rat-like and 350 kcps for a mouse-like phantom, respectively. Image quality phantom values and contrast recovery were comparable to state-of-the art PET-inserts and standalone systems. Regarding MR compatibility, changes in the mean signal-to-noise ratio for turbo spin echo and echo-planar imaging sequences were below 8.6%, for gradient echo sequences below 1%. Degradation of the mean homogeneity was below 2.3% for all tested sequences. The influence of the PET-insert on the B
0 maps was negligible and no influence on functional MRI sequences was detected. A mouse and rat imaging study demonstrated the feasibility of in vivo simultaneous PET/MRI.
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Min LA, Castagnoli F, Vogel WV, Vellenga JP, van Griethuysen JJM, Lahaye MJ, Maas M, Beets Tan RGH, Lambregts DMJ. A decade of multi-modality PET and MR imaging in abdominal oncology. Br J Radiol 2021; 94:20201351. [PMID: 34387508 PMCID: PMC9328040 DOI: 10.1259/bjr.20201351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES To investigate trends observed in a decade of published research on multimodality PET(/CT)+MR imaging in abdominal oncology, and to explore how these trends are reflected by the use of multimodality imaging performed at our institution. METHODS First, we performed a literature search (2009-2018) including all papers published on the multimodality combination of PET(/CT) and MRI in abdominal oncology. Retrieved papers were categorized according to a structured labelling system, including study design and outcome, cancer and lesion type under investigation and PET-tracer type. Results were analysed using descriptive statistics and evolutions over time were plotted graphically. Second, we performed a descriptive analysis of the numbers of MRI, PET/CT and multimodality PET/CT+MRI combinations (performed within a ≤14 days interval) performed during a similar time span at our institution. RESULTS Published research papers involving multimodality PET(/CT)+MRI combinations showed an impressive increase in numbers, both for retrospective combinations of PET/CT and MRI, as well as hybrid PET/MRI. Main areas of research included new PET-tracers, visual PET(/CT)+MRI assessment for staging, and (semi-)quantitative analysis of PET-parameters compared to or combined with MRI-parameters as predictive biomarkers. In line with literature, we also observed a vast increase in numbers of multimodality PET/CT+MRI imaging in our institutional data. CONCLUSIONS The tremendous increase in published literature on multimodality imaging, reflected by our institutional data, shows the continuously growing interest in comprehensive multivariable imaging evaluations to guide oncological practice. ADVANCES IN KNOWLEDGE The role of multimodality imaging in oncology is rapidly evolving. This paper summarizes the main applications and recent developments in multimodality imaging, with a specific focus on the combination of PET+MRI in abdominal oncology.
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Affiliation(s)
- Lisa A Min
- Department of Radiology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.,GROW School for Oncology and Developmental Biology, University of Maastricht, Maastricht, The Netherlands
| | | | - Wouter V Vogel
- Department of Nuclear Medicine, The Netherlands Cancer Institute, Amsterdam, The Netherlands.,Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Jisk P Vellenga
- Department of Radiology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.,Department of Nuclear Medicine, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Joost J M van Griethuysen
- Department of Radiology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.,GROW School for Oncology and Developmental Biology, University of Maastricht, Maastricht, The Netherlands
| | - Max J Lahaye
- Department of Radiology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Monique Maas
- Department of Radiology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Regina G H Beets Tan
- Department of Radiology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.,GROW School for Oncology and Developmental Biology, University of Maastricht, Maastricht, The Netherlands.,Faculty or Health Sciences, University of Southern Denmark, Odense, Denmark
| | - Doenja M J Lambregts
- Department of Radiology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
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Ur Rahman H, Wang G, Alam Bhuiyan MZ, Chen J. In-network generalized trustworthy data collection for event detection in cyber-physical systems. PeerJ Comput Sci 2021; 7:e504. [PMID: 34013032 PMCID: PMC8114821 DOI: 10.7717/peerj-cs.504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 04/02/2021] [Indexed: 06/12/2023]
Abstract
Sensors in Cyber-Physical Systems (CPS) are typically used to collect various aspects of the region of interest and transmit the data towards upstream nodes for further processing. However, data collection in CPS is often unreliable due to severe resource constraints (e.g., bandwidth and energy), environmental impacts (e.g., equipment faults and noises), and security concerns. Besides, detecting an event through the aggregation in CPS can be intricate and untrustworthy if the sensor's data is not validated during data acquisition, before transmission, and before aggregation. This paper introduces In-network Generalized Trustworthy Data Collection (IGTDC) framework for event detection in CPS. This framework facilitates reliable data for aggregation at the edge of CPS. The main idea of IGTDC is to enable a sensor's module to examine locally whether the event's acquired data is trustworthy before transmitting towards the upstream nodes. It further validates whether the received data can be trusted or not before data aggregation at the sink node. Additionally, IGTDC helps to identify faulty sensors. For reliable event detection, we use collaborative IoT tactics, gate-level modeling with Verilog User Defined Primitive (UDP), and Programmable Logic Device (PLD) to ensure that the event's acquired data is reliable before transmitting towards the upstream nodes. We employ Gray code in gate-level modeling. It helps to ensure that the received data is reliable. Gray code also helps to distinguish a faulty sensor. Through simulation and extensive performance analysis, we demonstrate that the collected data in the IGTDC framework is reliable and can be used in the majority of CPS applications.
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Affiliation(s)
- Hafiz Ur Rahman
- School of Computer Science, Guangzhou University, Guangzhou, Guangdong Province, China
| | - Guojun Wang
- School of Computer Science, Guangzhou University, Guangzhou, Guangdong Province, China
| | - Md Zakirul Alam Bhuiyan
- Department of Computer and Information Sciences, Fordham University, New York, NY, United States
| | - Jianer Chen
- School of Computer Science, Guangzhou University, Guangzhou, Guangdong Province, China
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Rausch I, Valladares A, Sundar LKS, Beyer T, Hacker M, Meyerspeer M, Unger E. Standard MRI-based attenuation correction for PET/MRI phantoms: a novel concept using MRI-visible polymer. EJNMMI Phys 2021; 8:18. [PMID: 33599876 DOI: 10.1186/s40658-021-00364-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/08/2021] [Indexed: 12/20/2022] Open
Abstract
Background PET/MRI phantom studies are challenged by the need of phantom-specific attenuation templates to account for attenuation properties of the phantom material. We present a PET/MRI phantom built from MRI-visible material for which attenuation correction (AC) can be performed using the standard MRI-based AC. Methods A water-fillable phantom was 3D-printed with a commercially available MRI-visible polymer. The phantom had a cylindrical shape and the fillable compartment consisted of a homogeneous region and a region containing solid rods of different diameters. The phantom was filled with a solution of water and [18F]FDG. A 30 min PET/MRI acquisition including the standard Dixon-based MR-AC method was performed. In addition, a CT scan of the phantom was acquired on a PET/CT system. From the Dixon in-phase, opposed-phase and fat images, a phantom-specific AC map (Phantom MR-AC) was produced by separating the phantom material from the water compartment using a thresholding-based method and assigning fixed attenuation coefficients to the individual compartments. The PET data was reconstructed using the Phantom MR-AC, the original Dixon MR-AC, and an MR-AC just containing the water compartment (NoWall-AC) to estimate the error of ignoring the phantom walls. CT-based AC was employed as the reference standard. Average %-differences in measured activity between the CT corrected PET and the PET corrected with the other AC methods were calculated. Results The phantom housing and the liquid compartment were both visible and distinguishable from each other in the Dixon images and allowed the segmentation of a phantom-specific MR-based AC. Compared to the CT-AC PET, average differences in measured activity in the whole water compartment in the phantom of −0.3%, 9.4%, and −24.1% were found for Dixon phantom MR-AC, MR-AC, and NoWall-AC based PET, respectively. Average differences near the phantom wall in the homogeneous region were −0.3%, 6.6%, and −34.3%, respectively. Around the rods, activity differed from the CT-AC PET by 0.7%, 8.9%, and −45.5%, respectively. Conclusion The presented phantom material is visible using standard MR sequences, and thus, supports the use of standard, phantom-independent MR measurements for MR-AC in PET/MRI phantom studies.
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Lim MS, Beyer T, Babayan A, Bergmann M, Brehme M, Buyx A, Czernin J, Egger G, Elenitoba-Johnson KSJ, Gückel B, Jačan A, Haslacher H, Hicks RJ, Kenner L, Langanke M, Mitterhauser M, Pichler BJ, Salih HR, Schibli R, Schulz S, Simecek J, Simon J, Soares MO, Stelzl U, Wadsak W, Zatloukal K, Zeitlinger M, Hacker M. Advancing Biomarker Development Through Convergent Engagement: Summary Report of the 2nd International Danube Symposium on Biomarker Development, Molecular Imaging and Applied Diagnostics; March 14-16, 2018; Vienna, Austria. Mol Imaging Biol 2020; 22:47-65. [PMID: 31049831 DOI: 10.1007/s11307-019-01361-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Here, we report on the outcome of the 2nd International Danube Symposium on advanced biomarker development that was held in Vienna, Austria, in early 2018. During the meeting, cross-speciality participants assessed critical aspects of non-invasive, quantitative biomarker development in view of the need to expand our understanding of disease mechanisms and the definition of appropriate strategies both for molecular diagnostics and personalised therapies. More specifically, panelists addressed the main topics, including the current status of disease characterisation by means of non-invasive imaging, histopathology and liquid biopsies as well as strategies of gaining new understanding of disease formation, modulation and plasticity to large-scale molecular imaging as well as integrative multi-platform approaches. Highlights of the 2018 meeting included dedicated sessions on non-invasive disease characterisation, development of disease and therapeutic tailored biomarkers, standardisation and quality measures in biospecimens, new therapeutic approaches and socio-economic challenges of biomarker developments. The scientific programme was accompanied by a roundtable discussion on identification and implementation of sustainable strategies to address the educational needs in the rapidly evolving field of molecular diagnostics. The central theme that emanated from the 2nd Donau Symposium was the importance of the conceptualisation and implementation of a convergent approach towards a disease characterisation beyond lesion-counting "lumpology" for a cost-effective and patient-centric diagnosis, therapy planning, guidance and monitoring. This involves a judicious choice of diagnostic means, the adoption of clinical decision support systems and, above all, a new way of communication involving all stakeholders across modalities and specialities. Moreover, complex diseases require a comprehensive diagnosis by converging parameters from different disciplines, which will finally yield to a precise therapeutic guidance and outcome prediction. While it is attractive to focus on technical advances alone, it is important to develop a patient-centric approach, thus asking "What can we do with our expertise to help patients?"
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Chen S, Gu Y, Yu H, Chen X, Cao T, Hu L, Shi H. NEMA NU2-2012 performance measurements of the United Imaging uPMR790: an integrated PET/MR system. Eur J Nucl Med Mol Imaging 2021; 48:1726-1735. [PMID: 33388972 DOI: 10.1007/s00259-020-05135-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 11/24/2020] [Indexed: 12/16/2022]
Abstract
PURPOSE In this paper, we aimed to evaluate the positron emission tomography (PET) performance of, to the best of our knowledge, the third commercially available whole-body integrated PET/magnetic resonance (MR) system. METHODS The PET system performance was measured following the NEMA standards with and without simultaneous MR operation. PET spatial resolution, sensitivity, scatter fraction, count-rate performance, accuracy of count losses and random corrections, image quality, and time-of-flight (TOF) resolution were quantitatively evaluated. Clinical scans were acquired at the PET/MR system and compared with images acquired at a PET/CT with the same digital detector technology. RESULTS Measurement results of essential PET performance were reported in the form of MR idle (MR pulsing). The axial, radial, and tangential spatial resolutions were measured as 2.72 mm (2.73 mm), 2.86 mm (2.85 mm), and 2.81 mm (2.82 mm) FWHM, respectively, at 1 cm radial offset. The NECR peak was measured as 129.2 kcps (129.5 kcps) at 14.7 kBq mL-1 (14.2 kBq mL-1). The scatter fraction at NECR peak was 37.9% (36.5%), and the maximum slice error below NECR was 4.1% (4.5%). Contrast recovery coefficients ranged from 51.8% (52.3%) for 10 mm hot sphere to 87.3% (87.2%) for 37 mm cold sphere. TOF resolution at 5.3 kBq mL-1 was measured at 535 ps (540 ps). With point source, TOF was measured to be 474 ps (485 ps). Clinical scans revealed similar image quality from the PET/MR and the comparative PET/CT system. CONCLUSION The PET performance of the newly introduced integrated PET/MR system is not significantly affected by the simultaneous operation of an MR sequence (2-point DIXON sequence). Measurement results demonstrate comparable performance with other state-of-the-art PET/MR systems. The clinical benefits of high spatial resolution and long axial coverage remain to be further evaluated in specific clinical imaging applications.
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Affiliation(s)
- Shuguang Chen
- Zhongshan Hospital, Fudan University, 1609 Xietu Road, Shanghai, 200032, China.,Institute of Nuclear Medicine, Fudan University, Shanghai, China
| | - Yushen Gu
- Zhongshan Hospital, Fudan University, 1609 Xietu Road, Shanghai, 200032, China.,Institute of Nuclear Medicine, Fudan University, Shanghai, China
| | - Haojun Yu
- Zhongshan Hospital, Fudan University, 1609 Xietu Road, Shanghai, 200032, China.,Institute of Nuclear Medicine, Fudan University, Shanghai, China
| | - Xin Chen
- United Imaging Healthcare Co., Ltd., Shanghai, China
| | - Tuoyu Cao
- United Imaging Healthcare Co., Ltd., Shanghai, China
| | - Lingzhi Hu
- United Imaging Healthcare Co., Ltd., Shanghai, China
| | - Hongcheng Shi
- Zhongshan Hospital, Fudan University, 1609 Xietu Road, Shanghai, 200032, China. .,Institute of Nuclear Medicine, Fudan University, Shanghai, China.
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Reich CM, Sattler B, Jochimsen TH, Unger M, Melzer L, Landgraf L, Barthel H, Sabri O, Melzer A. Practical setting and potential applications of interventions guided by PET/MRI. Q J Nucl Med Mol Imaging 2020; 65:43-50. [PMID: 33300750 DOI: 10.23736/s1824-4785.20.03293-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Multimodality imaging has emerged from a vision thirty years ago to routine clinical use today. Positron emission tomography (PET)/magnetic resonance imaging (MRI) is still relatively new in this arena and particularly suitable for clinical research and technical development. PET/MRI-guidance for interventions opens up opportunities for novel treatments but at the same time demands certain technical and organizational requirements to be fulfilled. In this work, we aimed to demonstrate a practical setting and potential application of PET/MRI guidance of interventional procedures. The superior quantitative physiologic information of PET, the various unique imaging characteristics of MRI, and the reduced radiation exposure are the most relevant advantages of this technique. As a noninvasive interventional tool, focused ultrasound (FUS) ablation of tumor cells would benefit from PET/MRI for diagnostics, treatment planning and intervention. Yet, technical limitations might impeed preclinical research, given that PET/MRI sites are per se not designed as interventional suites. Nonetheless, several approaches have been offered in the past years to upgrade MRI suites for interventional purposes. Taking advantage of state of the art and easy-to-use technology it is possible to create a supporting infrastructure that is suitable for broad preclinical adaption. Several aspects are to be addressed, including remote control of the imaging system, display of the imaging results, communication technology, and implementation of additional devices such as a FUS platform and an MR-compatible robotic system for positioning of the FUS equipment. Feasibility could be demostrated with an examplary experimental setup for interventional PET/MRI. Most PET/MRI sites could allow for interventions with just a few add-ons and modifications, such as comunication, in room image display and sytems control. By unlocking this feature, and driving preclinical research in interventional PET/MRI, translation of the protocol and methodology into clinical settings seems feasible.
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Affiliation(s)
- C Martin Reich
- Innovation Center Computer Assisted Surgery, University of Leipzig, Leipzig, Germany
| | - Bernhard Sattler
- Department of Nuclear Medicine, University Hospital Leipzig, Leipzig, Germany -
| | - Thies H Jochimsen
- Department of Nuclear Medicine, University Hospital Leipzig, Leipzig, Germany
| | - Michael Unger
- Innovation Center Computer Assisted Surgery, University of Leipzig, Leipzig, Germany
| | - Leon Melzer
- Innovation Center Computer Assisted Surgery, University of Leipzig, Leipzig, Germany
| | - Lisa Landgraf
- Innovation Center Computer Assisted Surgery, University of Leipzig, Leipzig, Germany
| | - Henryk Barthel
- Department of Nuclear Medicine, University Hospital Leipzig, Leipzig, Germany
| | - Osama Sabri
- Department of Nuclear Medicine, University Hospital Leipzig, Leipzig, Germany
| | - Andreas Melzer
- Innovation Center Computer Assisted Surgery, University of Leipzig, Leipzig, Germany.,Institute for Medical Science and Technology IMSaT, University Dundee, Scotland, UK
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Soret M, Maisonobe JA, Payen S, Gaubert A, Brunel S, Rozemblum L, Hubert E, Kas A. Radiation dose of nuclear medicine technicians performing PET/MR. J Radiol Prot 2020; 40:861-866. [PMID: 32590378 DOI: 10.1088/1361-6498/aba082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Since october 2015, PET/MR has been used extensively for clinical routine in the nuclear medicine department of the Pitié-Salpêtrière Hospital (Paris, France) with a throughput of 11 to 15 patients each day. While many studies have been conducted to investigate dose reduction strategies to patients with hybrid PET/MR devices, no study has focused on staff radiation safety. Knowing that patient positioning within the scanner takes longer in PET/MR than in PET/CT because of the placement of several local MR receive coils, a retrospective study was carried out to measure the radiation doses to nuclear medicine technologists from the patient. The analysis was conducted during one year on 1332 clinical PET/MR studies performed with the Signa PET/MR system (General Electric Healthcare) in our department. The whole-body exposure of the technologist staff was on average for all PET/MR exams10.3 ± 4 nSv per injected MBq of 18 F. When performing brain PET/MR exams only, the whole-body exposure was on average 8.7 ± 2 nSv per injected MBq of 18 F. Brain PET/MR provides lower radiation dose than whole-body examinations for cancer screening due to a lower injected activity (2 vs. 3 MBq kg-1) and shorter patient positioning (5 vs. 15 min). When starting PET/MR in a nuclear medicine department, an important step is to optimise patient positionning within the scanner to minimise radiation dose received by the technical staff from patients.
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Affiliation(s)
- Marine Soret
- AP-HP, Hôpital Pitié-Salpêtrière, Médecine Nucléaire, Paris F-75013 France. CNRS, INSERM, Laboratoire d'Imagerie Biomédicale, LIB, Sorbonne Université, Paris F-75006 France
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Panda A, Goenka AH, Hope TA, Veit-Haibach P. PET/Magnetic Resonance Imaging Applications in Abdomen and Pelvis. Magn Reson Imaging Clin N Am 2020; 28:369-380. [DOI: 10.1016/j.mric.2020.03.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Abstract
PURPOSE OF REVIEW Hybrid PET- MRI is a technique that has the ability to improve diagnostic accuracy in many applications, whereas PET and MRI performed separately often fail to provide accurate responses to clinical questions. Here, we review recent studies and current developments in PET-MRI, focusing on clinical applications. RECENT FINDINGS The combination of PET and MRI imaging methods aims at increasing the potential of each individual modality. Combined methods of image reconstruction and correction of PET-MRI attenuation are being developed, and a number of applications are being introduced into clinical practice. To date, the value of PET-MRI has been demonstrated for the evaluation of brain tumours in epilepsy and neurodegenerative diseases. Continued advances in data analysis regularly improve the efficiency and the potential application of multimodal biomarkers. SUMMARY PET-MRI provides simultaneous of anatomical, functional, biochemical and metabolic information for the personalized characterization and monitoring of neurological diseases. In this review, we show the advantage of the complementarity of different biomarkers obtained using PET-MRI data. We also present the recent advances made in this hybrid imaging modality and its advantages in clinical practice compared with MRI and PET separately.
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Beyer T, Bidaut L, Dickson J, Kachelriess M, Kiessling F, Leitgeb R, Ma J, Shiyam Sundar LK, Theek B, Mawlawi O. What scans we will read: imaging instrumentation trends in clinical oncology. Cancer Imaging 2020; 20:38. [PMID: 32517801 PMCID: PMC7285725 DOI: 10.1186/s40644-020-00312-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 04/17/2020] [Indexed: 12/16/2022] Open
Abstract
Oncological diseases account for a significant portion of the burden on public healthcare systems with associated costs driven primarily by complex and long-lasting therapies. Through the visualization of patient-specific morphology and functional-molecular pathways, cancerous tissue can be detected and characterized non-invasively, so as to provide referring oncologists with essential information to support therapy management decisions. Following the onset of stand-alone anatomical and functional imaging, we witness a push towards integrating molecular image information through various methods, including anato-metabolic imaging (e.g., PET/CT), advanced MRI, optical or ultrasound imaging. This perspective paper highlights a number of key technological and methodological advances in imaging instrumentation related to anatomical, functional, molecular medicine and hybrid imaging, that is understood as the hardware-based combination of complementary anatomical and molecular imaging. These include novel detector technologies for ionizing radiation used in CT and nuclear medicine imaging, and novel system developments in MRI and optical as well as opto-acoustic imaging. We will also highlight new data processing methods for improved non-invasive tissue characterization. Following a general introduction to the role of imaging in oncology patient management we introduce imaging methods with well-defined clinical applications and potential for clinical translation. For each modality, we report first on the status quo and, then point to perceived technological and methodological advances in a subsequent status go section. Considering the breadth and dynamics of these developments, this perspective ends with a critical reflection on where the authors, with the majority of them being imaging experts with a background in physics and engineering, believe imaging methods will be in a few years from now. Overall, methodological and technological medical imaging advances are geared towards increased image contrast, the derivation of reproducible quantitative parameters, an increase in volume sensitivity and a reduction in overall examination time. To ensure full translation to the clinic, this progress in technologies and instrumentation is complemented by advances in relevant acquisition and image-processing protocols and improved data analysis. To this end, we should accept diagnostic images as “data”, and – through the wider adoption of advanced analysis, including machine learning approaches and a “big data” concept – move to the next stage of non-invasive tumour phenotyping. The scans we will be reading in 10 years from now will likely be composed of highly diverse multi-dimensional data from multiple sources, which mandate the use of advanced and interactive visualization and analysis platforms powered by Artificial Intelligence (AI) for real-time data handling by cross-specialty clinical experts with a domain knowledge that will need to go beyond that of plain imaging.
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Affiliation(s)
- Thomas Beyer
- QIMP Team, Centre for Medical Physics and Biomedical Engineering, Medical University Vienna, Währinger Gürtel 18-20/4L, 1090, Vienna, Austria.
| | - Luc Bidaut
- College of Science, University of Lincoln, Lincoln, UK
| | - John Dickson
- Institute of Nuclear Medicine, University College London Hospital, London, UK
| | - Marc Kachelriess
- Division of X-ray imaging and CT, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120, Heidelberg, DE, Germany
| | - Fabian Kiessling
- Institute for Experimental Molecular Imaging, University Clinic and Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Pauwelsstrasse 20, 52074, Aachen, DE, Germany.,Fraunhofer Institute for Digital Medicine MEVIS, Am Fallturm 1, 28359, Bremen, DE, Germany
| | - Rainer Leitgeb
- Centre for Medical Physics and Biomedical Engineering, Medical University Vienna, Vienna, AT, Austria
| | - Jingfei Ma
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Lalith Kumar Shiyam Sundar
- QIMP Team, Centre for Medical Physics and Biomedical Engineering, Medical University Vienna, Währinger Gürtel 18-20/4L, 1090, Vienna, Austria
| | - Benjamin Theek
- Institute for Experimental Molecular Imaging, University Clinic and Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Pauwelsstrasse 20, 52074, Aachen, DE, Germany.,Fraunhofer Institute for Digital Medicine MEVIS, Am Fallturm 1, 28359, Bremen, DE, Germany
| | - Osama Mawlawi
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
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Sekine T, Buck A, Delso G, Kemp B, Ter Voert EEGW, Huellner M, Veit-Haibach P, Kaushik S, Wiesinger F, Warnock G; Alzheimer’s Disease Neuroimaging Initiative. The impact of atlas-based MR attenuation correction on the diagnosis of FDG-PET/MR for Alzheimer's diseases- A simulation study combining multi-center data and ADNI-data. PLoS One 2020; 15:e0233886. [PMID: 32492074 DOI: 10.1371/journal.pone.0233886] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 05/14/2020] [Indexed: 11/19/2022] Open
Abstract
Background The purpose of this study was to assess the impact of vendor-provided atlas-based MRAC on FDG PET/MR for the evaluation of Alzheimer’s disease (AD) by using simulated images. Methods We recruited 47 patients, from two institutions, who underwent PET/CT and PET/MR (GE SIGNA) examination for oncological staging. From the PET raw data acquired on PET/MR, two FDG-PET series were generated, using vendor-provided MRAC (atlas-based) and CTAC. The following simulation steps were performed in MNI space: After spatial normalization and smoothing of the PET datasets, we calculated the error map for each patient, PETMRAC/PETCTAC. We multiplied each of these 47 error maps with each of the 203 Alzheimer’s Disease Neuroimaging Initiative (ADNI) cases after the identical normalization and smoothing. This resulted in 203*47 = 9541 datasets. To evaluate the probability of AD in each resulting image, a cumulative t-value was calculated automatically using commercially-available software (PMOD PALZ) which has been used in multiple large cohort studies. The diagnostic accuracy for the discrimination of AD and predicting progression from mild cognitive impairment (MCI) to AD were evaluated in simulated images compared with ADNI original images. Results The accuracy and specificity for the discrimination of AD-patients from normal controls were not substantially impaired, but sensitivity was slightly impaired in 5 out of 47 datasets (original vs. error; 83.2% [CI 75.0%-89.0%], 83.3% [CI 74.2%-89.8%] and 83.1% [CI 75.6%-88.3%] vs. 82.7% [range 80.4–85.0%], 78.5% [range 72.9–83.3%,] and 86.1% [range 81.4–89.8%]). The accuracy, sensitivity and specificity for predicting progression from MCI to AD during 2-year follow-up was not impaired (original vs. error; 62.5% [CI 53.3%-69.3%], 78.8% [CI 65.4%-88.6%] and 54.0% [CI 47.0%-69.1%] vs. 64.8% [range 61.5–66.7%], 75.7% [range 66.7–81.8%,] and 59.0% [range 50.8–63.5%]). The worst 3 error maps show a tendency towards underestimation of PET scores. Conclusion FDG-PET/MR based on atlas-based MR attenuation correction showed similar diagnostic accuracy to the CT-based method for the diagnosis of AD and the prediction of progression of MCI to AD using commercially-available software, although with a minor reduction in sensitivity.
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Abstract
Hybrid imaging using PET/MRI has emerged as a platform for elucidating novel neurobiology, molecular and functional changes in disease, and responses to physiological or pharmacological interventions. For the central nervous system, PET/MRI has provided insights into biochemical processes, linking selective molecular targets and distributed brain function. This review highlights several examples that leverage the strengths of simultaneous PET/MRI, which includes measuring the perturbation of multi-modal imaging signals on dynamic timescales during pharmacological challenges, physiological interventions or behavioral tasks. We discuss important considerations for the experimental design of dynamic PET/MRI studies and data analysis approaches for comparing and quantifying simultaneous PET/MRI data. The primary focus of this review is on functional PET/MRI studies of neurotransmitter and receptor systems, with an emphasis on the dopamine, opioid, serotonin and glutamate systems as molecular neuromodulators. In this context, we provide an overview of studies that employ interventions to alter the activity of neuroreceptors or the release of neurotransmitters. Overall, we emphasize how the synergistic use of simultaneous PET/MRI with appropriate study design and interventions has the potential to expand our knowledge about the molecular and functional dynamics of the living human brain. Finally, we give an outlook on the future opportunities for simultaneous PET/MRI.
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Affiliation(s)
- Christin Y Sander
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, MA, USA
| | - Hanne D Hansen
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, MA, USA.,Neurobiology Research Unit and NeuroPharm, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Hsiao-Ying Wey
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, MA, USA
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Mackewn JE, Stirling J, Jeljeli S, Gould SM, Johnstone RI, Merida I, Pike LC, McGinnity CJ, Beck K, Howes O, Hammers A, Marsden PK. Practical issues and limitations of brain attenuation correction on a simultaneous PET-MR scanner. EJNMMI Phys 2020; 7:24. [PMID: 32372135 PMCID: PMC7200964 DOI: 10.1186/s40658-020-00295-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 03/27/2020] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Despite the advent of clinical PET-MR imaging for routine use in 2011 and the development of several methods to address the problem of attenuation correction, some challenges remain. We have identified and investigated several issues that might affect the reliability and accuracy of current attenuation correction methods when these are implemented for clinical and research studies of the brain. These are (1) the accuracy of converting CT Hounsfield units, obtained from an independently acquired CT scan, to 511 keV linear attenuation coefficients; (2) the effect of padding used in the MR head coil; (3) the presence of close-packed hair; (4) the effect of headphones. For each of these, we have examined the effect on reconstructed PET images and evaluated practical mitigating measures. RESULTS Our major findings were (1) for both Siemens and GE PET-MR systems, CT data from either a Siemens or a GE PET-CT scanner may be used, provided the conversion to 511 keV μ-map is performed by the PET-MR vendor's own method, as implemented on their PET-CT scanner; (2) the effect of the head coil pads is minimal; (3) the effect of dense hair in the field of view is marked (> 10% error in reconstructed PET images); and (4) using headphones and not including them in the attenuation map causes significant errors in reconstructed PET images, but the risk of scanning without them may be acceptable following sound level measurements. CONCLUSIONS It is important that the limitations of attenuation correction in PET-MR are considered when designing research and clinical PET-MR protocols in order to enable accurate quantification of brain PET scans. Whilst the effect of pads is not significant, dense hair, the use of headphones and the use of an independently acquired CT-scan can all lead to non-negligible effects on PET quantification. Although seemingly trivial, these effects add complications to setting up protocols for clinical and research PET-MR studies that do not occur with PET-CT. In the absence of more sophisticated PET-MR brain attenuation correction, the effect of all of the issues above can be minimised if the pragmatic approaches presented in this work are followed.
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Affiliation(s)
- J. E. Mackewn
- King’s College London and Guy’s and St Thomas’ PET Centre, School of Biomedical Engineering and Imaging Sciences, King’s College London, London, UK
| | - J. Stirling
- King’s College London and Guy’s and St Thomas’ PET Centre, School of Biomedical Engineering and Imaging Sciences, King’s College London, London, UK
| | - S. Jeljeli
- King’s College London and Guy’s and St Thomas’ PET Centre, School of Biomedical Engineering and Imaging Sciences, King’s College London, London, UK
| | - S-M. Gould
- King’s College London and Guy’s and St Thomas’ PET Centre, School of Biomedical Engineering and Imaging Sciences, King’s College London, London, UK
| | - R. I. Johnstone
- King’s College London and Guy’s and St Thomas’ PET Centre, School of Biomedical Engineering and Imaging Sciences, King’s College London, London, UK
- Guy’s and St. Thomas’ NHS Foundation Trust, London, UK
| | - I. Merida
- CERMEP-Imagerie du vivant, Lyon, France
| | - L. C. Pike
- King’s College London and Guy’s and St Thomas’ PET Centre, School of Biomedical Engineering and Imaging Sciences, King’s College London, London, UK
| | - C. J. McGinnity
- King’s College London and Guy’s and St Thomas’ PET Centre, School of Biomedical Engineering and Imaging Sciences, King’s College London, London, UK
| | - K. Beck
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London, UK
- South London and the Maudsley NHS Foundation Trust, London, UK
| | - O. Howes
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London, UK
- South London and the Maudsley NHS Foundation Trust, London, UK
- MRC London Institute of Medical Sciences, Hammersmith Hospital Campus, London, UK
| | - A. Hammers
- King’s College London and Guy’s and St Thomas’ PET Centre, School of Biomedical Engineering and Imaging Sciences, King’s College London, London, UK
| | - P. K. Marsden
- King’s College London and Guy’s and St Thomas’ PET Centre, School of Biomedical Engineering and Imaging Sciences, King’s College London, London, UK
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Créhange G, Soussan M, Gensanne D, Decazes P, Thariat J, Thureau S. Interest of positron-emission tomography and magnetic resonance imaging for radiotherapy planning and control. Cancer Radiother 2020; 24:398-402. [PMID: 32247688 DOI: 10.1016/j.canrad.2020.02.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 02/07/2020] [Indexed: 12/24/2022]
Abstract
Computed tomography (CT) in the treatment position is currently indispensable for planning radiation therapy. Other imaging modalities, such as magnetic resonance imaging (MRI) and positron emission-tomography (PET), can be used to improve the definition of the tumour and/or healthy tissue but also to provide functional data of the target volume. Accurate image registration is essential for treatment planning, so MRI and PET scans should be registered at the planning CT scan. Hybrid PET/MRI scans with a hard plane can be used but pose the problem of the absence of CT scans. Finally, techniques for moving the patient on a rigid air-cushioned table allow PET/CT/MRI scans to be performed in the treatment position while limiting the patient's movements exist. At the same time, the advent of MRI-linear accelerator systems allows to redefine image-guided radiotherapy and to propose treatments with daily recalculation of the dose. The place of PET during treatment remains more confidential and currently only in research and prototype status. The same development of imaging during radiotherapy is underway in proton therapy.
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Affiliation(s)
- G Créhange
- Département de radiothérapie oncologique, institut Curie, 26, rue d'Ulm, 75005 Paris, France
| | - M Soussan
- Service de médecine nucléaire, hôpital Avicenne, AP-HP, hôpitaux universitaires, 125, rue de Stalingrad, 93000 Bobigny, France
| | - D Gensanne
- Département de radiothérapie et de physique médicale, centre Henri-Becquerel, 1, rue d'Amiens, 76038 Rouen, France; Quantif-Litis EA4108, université de Rouen Normandie, rue d'Amiens, 76000 Rouen, France
| | - P Decazes
- Quantif-Litis EA4108, université de Rouen Normandie, rue d'Amiens, 76000 Rouen, France; Département d'imagerie-médecine nucléaire, centre Henri-Becquerel, 1, rue d'Amiens, 76038 Rouen, France
| | - J Thariat
- Département d'onco-radiothérapie, centre François-Baclesse, 3, avenue General-Harris, 14000 Caen, France; Association Advance Resource Centre for Hadrontherapy in Europe (Archade), 3, avenue General-Harris, 14000 Caen, France; Université de Caen Normandie (Unicaen), 3, avenue General-Harris, 14000 Caen, France; Laboratoire de physique corpusculaire, Institut national de physique nucléaire et de physique des particules (IN2P3), 6, boulevard Maréchal-Juin, 14000 Caen, France
| | - S Thureau
- Département de radiothérapie et de physique médicale, centre Henri-Becquerel, 1, rue d'Amiens, 76038 Rouen, France; Quantif-Litis EA4108, université de Rouen Normandie, rue d'Amiens, 76000 Rouen, France; Département d'imagerie-médecine nucléaire, centre Henri-Becquerel, 1, rue d'Amiens, 76038 Rouen, France; Laboratoire de physique corpusculaire, Institut national de physique nucléaire et de physique des particules (IN2P3), 6, boulevard Maréchal-Juin, 14000 Caen, France.
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Mada MO, Hindmarch P, Stirling J, Davies J, Brian D, Barnes A, Hammers A, Gulliver N, Herholz K, O'Brien J, Taylor JP. Competencies and training of radiographers and technologists for PET/MR imaging - a study from the UK MR-PET network. Eur J Hybrid Imaging 2020; 4:1. [PMID: 32025619 DOI: 10.1186/s41824-019-0070-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 12/23/2019] [Indexed: 11/10/2022] Open
Abstract
Background After the success of PET/CT as a clinical diagnostic tool, the introduction of PET/MRI is a natural development aimed at further improving combined diagnostic imaging and reduced ionising radiation dose for half-body imaging. As with PET and CT, the combination of PET and MRI presents a series of issues that need to be addressed regarding workforce training and education. At present, there is a lack of agreement over the competencies, training requirements and educational pathways needed for PET/MRI operation. In the UK, following the establishment of the MR-PET imaging network, a task force was created to investigate the status of the workforce training, identify gaps and make recommendations regarding staff training. To do this, we ran a national survey on the status of the workforce training and the local practices across the UK’s seven PET/MRI sites, reviewed the literature, and convened a panel of experts, to assess all the evidence and make recommendations regarding PET/MRI competencies and training of nuclear medicine technologists and radiographers. Results There is limited literature available specifically on competencies and training for technologists and radiographers. The recommendations on the topic needed revisiting and adapting to the UK MR-PET network. The online survey confirmed the need for developing PET/MRI competencies and training pathways. Local organisational structures and practices were shared across the seven sites, based on models derived from experience outside the UK. The panel of experts agreed on the need for PET/MRI competencies and training strategies. Professional organisations started collaborative discussions with partners from both Nuclear Medicine and Radiography to set training priorities. Multidisciplinary collaboration and partnership were suggested as a key to a successful implementation of competencies and training. Conclusions The report identified the need for establishing competencies for the PET/MRI workforce, particularly for technologists and radiographers. It also helped defining these competencies as well as identifying the demand for bespoke training and the development of local and national courses to be implemented to fulfil this new training need.
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Peerlings J, Paulis L, Mitea C, Bakers F, Berbée M, Wierts R, Vöö S, Wildberger J, Hoffmann A, Lambin P, Mottaghy F. Performing clinical 18F-FDG-PET/MRI of the mediastinum optimising a dedicated, patient-friendly protocol. Nucl Med Commun 2019; 40:815-26. [PMID: 31169592 DOI: 10.1097/MNM.0000000000001035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE To construct a mediastinal-specific fluorine-18-fluorodeoxyglucose (F-FDG)-PET/MR protocol with high-quality MRI of minimal acquisition-time and comparable diagnostic value to F-FDG-PET/computed tomography (CT). MATERIALS AND METHODS Fifteen healthy participants received PET/MRI and 10 patients with mediastinal tumours (eight non-small-cell lung, two oesophageal cancer) received F-FDG-PET/MRI immediately after F-FDG-PET/CT. Sequences volume interpolated breath-hold examination (T1-VIBE) and Half-Fourier acquisition single-shot turbo spin echo (T2-HASTE) were optimised by varying the parameters: breath-hold (BH, end-expiration), fat suppression (spectral adiabatic inversion recovery), and ECG-triggering (ECG, end-diastole). Image quality (IQ) of each sequence-variation was qualitatively scored by medical experts and quantitatively assessed by calculating signal-to-noise ratios, contrast relative to muscle, standardized-uptake-value, and tumour-to-blood ratios. Patient comfort was evaluated on patients' experience. Diagnostic accuracy of F-FDG-PET/MRI was compared to F-FDG-PET/CT, in reference to histopathology/cytopathology. RESULTS ECG-triggered T1-VIBE images showed the highest signal-to-noise ratio (P < 0.01) and the largest contrast between mediastinal soft-tissues, regardless of BH or free-breathing acquisition. IQ of ECG-triggered T1-VIBE scans in BH were scored qualitatively highest with good reader agreement (κ = 0.62). IQ of T2-HASTE was not significantly affected by BH acquisition (P > 0.9). Qualitative IQ of T1-VIBE and T2-HASTE declined after spectral adiabatic inversion recovery fat-suppression. All patients could maintain BH at end-expiration and reported no discomfort. Diagnostic performance of F-FDG-PET/MR was not significantly different from F-FDG-PET/CT with comparable staging, standardized-uptake-values, and tumour-to-blood ratios. However, T-status was more often over-staged on F-FDG-PET/CT, while N-status was more frequently under-staged on F-FDG-PET/MR. CONCLUSION ECG-triggered T1-VIBE sequences acquired during short, multiple BHs are recommended for mediastinal imaging using F-FDG-PET/MR. With dedicated protocols, F-FDG-PET/MRI will be useful in thoracic oncology and aid in diagnostic evaluation and tailored treatment decision-making.
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Tamaki N, Matsushima S, Nishimura M. Value of simultaneous assessment of cardiac functions by PET/MRI. J Nucl Cardiol 2019; 26:1958-1961. [PMID: 30030784 DOI: 10.1007/s12350-018-1341-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 06/11/2018] [Indexed: 12/21/2022]
Affiliation(s)
- Nagara Tamaki
- Department of Radiology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto, 602-8566, Japan.
| | - Shigenori Matsushima
- Department of Radiology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto, 602-8566, Japan
| | - Motoki Nishimura
- Department of Radiology, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto, 602-8566, Japan
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Ruiz-Bedoya CA, Gordon O, Mota F, Abhishek S, Tucker EW, Ordonez AA, Jain SK. Molecular Imaging of Diabetic Foot Infections: New Tools for Old Questions. Int J Mol Sci 2019; 20:E5984. [PMID: 31795077 DOI: 10.3390/ijms20235984] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 11/20/2019] [Accepted: 11/26/2019] [Indexed: 02/07/2023] Open
Abstract
Diabetic foot infections (DFIs) are a common, complex, and costly medical problem with increasing prevalence. Diagnosing DFIs is a clinical challenge due to the poor specificity of the available methods to accurately determine the presence of infection in these patients. However, failure to perform an opportune diagnosis and provide optimal antibiotic therapy can lead to higher morbidity for the patient, unnecessary amputations, and increased healthcare costs. Novel developments in bacteria-specific molecular imaging can provide a non-invasive assessment of the infection site to support diagnosis, determine the extension and location of the infection, guide the selection of antibiotics, and monitor the response to treatment. This is a review of recent research in molecular imaging of infections in the context of DFI. We summarize different clinical and preclinical methods and the translational implications aimed to improve the care of patients with DFI.
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Kaissis G, Ziegelmayer S, Lohöfer F, Steiger K, Algül H, Muckenhuber A, Yen HY, Rummeny E, Friess H, Schmid R, Weichert W, Siveke JT, Braren R. A machine learning algorithm predicts molecular subtypes in pancreatic ductal adenocarcinoma with differential response to gemcitabine-based versus FOLFIRINOX chemotherapy. PLoS One 2019; 14:e0218642. [PMID: 31577805 PMCID: PMC6774515 DOI: 10.1371/journal.pone.0218642] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 09/19/2019] [Indexed: 12/13/2022] Open
Abstract
PURPOSE Development of a supervised machine-learning model capable of predicting clinically relevant molecular subtypes of pancreatic ductal adenocarcinoma (PDAC) from diffusion-weighted-imaging-derived radiomic features. METHODS The retrospective observational study assessed 55 surgical PDAC patients. Molecular subtypes were defined by immunohistochemical staining of KRT81. Tumors were manually segmented and 1606 radiomic features were extracted with PyRadiomics. A gradient-boosted-tree algorithm was trained on 70% of the patients (N = 28) and tested on 30% (N = 17) to predict KRT81+ vs. KRT81- tumor subtypes. A gradient-boosted survival regression model was fit to the disease-free and overall survival data. Chemotherapy response and survival were assessed stratified by subtype and radiomic signature. Radiomic feature importance was ranked. RESULTS The mean±STDEV sensitivity, specificity and ROC-AUC were 0.90±0.07, 0.92±0.11, and 0.93±0.07, respectively. The mean±STDEV concordance indices between the disease-free and overall survival predicted by the model based on the radiomic parameters and actual patient survival were 0.76±0.05 and 0.71±0.06, respectively. Patients with a KRT81+ subtype experienced significantly diminished median overall survival compared to KRT81- patients (7.0 vs. 22.6 months, HR 4.03, log-rank-test P = <0.001) and a significantly improved response to gemcitabine-based chemotherapy over FOLFIRINOX (10.14 vs. 3.8 months median overall survival, HR 2.33, P = 0.037) compared to KRT81- patients, who responded significantly better to FOLFIRINOX over gemcitabine-based treatment (30.8 vs. 13.4 months median overall survival, HR 2.41, P = 0.027). Entropy was ranked as the most important radiomic feature. CONCLUSIONS The machine-learning based analysis of radiomic features enables the prediction of subtypes of PDAC, which are highly relevant for disease-free and overall patient survival and response to chemotherapy.
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Affiliation(s)
- Georgios Kaissis
- Department of Diagnostic and Interventional Radiology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Sebastian Ziegelmayer
- Department of Diagnostic and Interventional Radiology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Fabian Lohöfer
- Department of Diagnostic and Interventional Radiology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Katja Steiger
- Department of Pathology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Hana Algül
- Department of Internal Medicine II, School of Medicine, Technical University of Munich, Munich, Germany
| | - Alexander Muckenhuber
- Department of Pathology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Hsi-Yu Yen
- Department of Pathology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Ernst Rummeny
- Department of Diagnostic and Interventional Radiology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Helmut Friess
- Department of Surgery, School of Medicine, Technical University of Munich, Munich, Germany
| | - Roland Schmid
- Department of Internal Medicine II, School of Medicine, Technical University of Munich, Munich, Germany
| | - Wilko Weichert
- Department of Pathology, School of Medicine, Technical University of Munich, Munich, Germany
| | - Jens T. Siveke
- Division of Solid Tumor Translational Oncology, West German Cancer Center, University Hospital Essen, Essen, Germany
- German Cancer Consortium (DKTK) and German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Rickmer Braren
- Department of Diagnostic and Interventional Radiology, School of Medicine, Technical University of Munich, Munich, Germany
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Sundar LK, Muzik O, Rischka L, Hahn A, Rausch I, Lanzenberger R, Hienert M, Klebermass EM, Füchsel FG, Hacker M, Pilz M, Pataraia E, Traub-Weidinger T, Beyer T. Towards quantitative [18F]FDG-PET/MRI of the brain: Automated MR-driven calculation of an image-derived input function for the non-invasive determination of cerebral glucose metabolic rates. J Cereb Blood Flow Metab 2019; 39:1516-1530. [PMID: 29790820 PMCID: PMC6681439 DOI: 10.1177/0271678x18776820] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Absolute quantification of PET brain imaging requires the measurement of an arterial input function (AIF), typically obtained invasively via an arterial cannulation. We present an approach to automatically calculate an image-derived input function (IDIF) and cerebral metabolic rates of glucose (CMRGlc) from the [18F]FDG PET data using an integrated PET/MRI system. Ten healthy controls underwent test-retest dynamic [18F]FDG-PET/MRI examinations. The imaging protocol consisted of a 60-min PET list-mode acquisition together with a time-of-flight MR angiography scan for segmenting the carotid arteries and intermittent MR navigators to monitor subject movement. AIFs were collected as the reference standard. Attenuation correction was performed using a separate low-dose CT scan. Assessment of the percentage difference between area-under-the-curve of IDIF and AIF yielded values within ±5%. Similar test-retest variability was seen between AIFs (9 ± 8) % and the IDIFs (9 ± 7) %. Absolute percentage difference between CMRGlc values obtained from AIF and IDIF across all examinations and selected brain regions was 3.2% (interquartile range: (2.4-4.3) %, maximum < 10%). High test-retest intravariability was observed between CMRGlc values obtained from AIF (14%) and IDIF (17%). The proposed approach provides an IDIF, which can be effectively used in lieu of AIF.
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Affiliation(s)
- Lalith Ks Sundar
- 1 QIMP Group, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Otto Muzik
- 2 Department of Radiology, Wayne State University School of Medicine, The Detroit Medical Center, Children's Hospital of Michigan, Detroit, MI, USA
| | - Lucas Rischka
- 3 Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
| | - Andreas Hahn
- 3 Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
| | - Ivo Rausch
- 1 QIMP Group, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Rupert Lanzenberger
- 3 Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
| | - Marius Hienert
- 3 Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
| | - Eva-Maria Klebermass
- 4 Division of Nuclear Medicine, Department of Biomedical imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Frank-Günther Füchsel
- 5 Institute for Radiology and Nuclear Medicine, Stadtspital Waid Zurich, Zurich, Switzerland
| | - Marcus Hacker
- 4 Division of Nuclear Medicine, Department of Biomedical imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Magdalena Pilz
- 4 Division of Nuclear Medicine, Department of Biomedical imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Ekaterina Pataraia
- 6 Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Tatjana Traub-Weidinger
- 4 Division of Nuclear Medicine, Department of Biomedical imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Thomas Beyer
- 1 QIMP Group, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
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Castiglioni I, Gallivanone F, Soda P, Avanzo M, Stancanello J, Aiello M, Interlenghi M, Salvatore M. AI-based applications in hybrid imaging: how to build smart and truly multi-parametric decision models for radiomics. Eur J Nucl Med Mol Imaging 2019; 46:2673-99. [PMID: 31292700 DOI: 10.1007/s00259-019-04414-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 06/21/2019] [Indexed: 12/13/2022]
Abstract
INTRODUCTION The quantitative imaging features (radiomics) that can be obtained from the different modalities of current-generation hybrid imaging can give complementary information with regard to the tumour environment, as they measure different morphologic and functional imaging properties. These multi-parametric image descriptors can be combined with artificial intelligence applications into predictive models. It is now the time for hybrid PET/CT and PET/MRI to take the advantage offered by radiomics to assess the added clinical benefit of using multi-parametric models for the personalized diagnosis and prognosis of different disease phenotypes. OBJECTIVE The aim of the paper is to provide an overview of current challenges and available solutions to translate radiomics into hybrid PET-CT and PET-MRI imaging for a smart and truly multi-parametric decision model.
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Chen S, Hu P, Gu Y, Pang L, Zhang Z, Zhang Y, Meng X, Cao T, Liu X, Fan Z, Shi H. Impact of patient comfort on diagnostic image quality during PET/MR exam: A quantitative survey study for clinical workflow management. J Appl Clin Med Phys 2019; 20:184-192. [PMID: 31207077 PMCID: PMC6612685 DOI: 10.1002/acm2.12664] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2018] [Revised: 05/05/2019] [Accepted: 05/23/2019] [Indexed: 12/26/2022] Open
Abstract
Background PET/MR is transferring from a powerful scientific research tool to an imaging modality in clinical routine practice. Whole body PET/MR screening usually takes 30–50 minutes to finish, during which a few factors might induce patient discomfort and further cause degraded image quality. The aim of this report is to investigate the patients' perception of the imaging procedure and its correlation with image quality. Methods One hundred and twenty patients (63 males and 57 females, average age = 51.3 years, range 22–70 years) who had been diagnosed with cancer or had previous history of cancer were recruited and scanned with a simultaneous PET/MR system. A questionnaire was given to all patients retrospectively after the PET/MR scan, which has nine questions to assess patients' feeling of the scan on a Likert scale scoring system (1–5, 1 as most satisfied). All PET/MR images were also visually examined by two experts independently to evaluate the quality of the images. Six body locations were assessed and each location was evaluated also with a Likert scale scoring system (1–5, 5 as the best quality). Mann–Whitney Utest was used for statistical analysis to check if there is significant correlation between image quality and patient perceptions. Results With a total of 120 patients, 118 questionnaires were filled and returned for analysis. The patients’ characteristics were summarized in Table 4. The statistics of the patients’ perception in the questionnaire were illustrated in Tables 5–7. Statistical significant correlations were found between MR image quality and patients’ characteristics/perception. Conclusion Our results show that PET/MR scanning is generally safe and comfortable for most of the patients. Statistical analysis does not support the hypothesis that bad patient’s perception leads to degraded image quality.
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Affiliation(s)
- Shuguang Chen
- Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Pengcheng Hu
- Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yusen Gu
- Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Lifang Pang
- Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Zheng Zhang
- United Imaging Healthcare Co., Ltd, Shanghai, China
| | - Yiqian Zhang
- United Imaging Healthcare Co., Ltd, Shanghai, China
| | - Xiaolin Meng
- United Imaging Healthcare Co., Ltd, Shanghai, China
| | - Tuoyu Cao
- United Imaging Healthcare Co., Ltd, Shanghai, China
| | - Xin Liu
- Center for Certification an Evaluation, Shanghai Food and Drug Administration, Shanghai, China
| | - Zhijin Fan
- Center for Certification an Evaluation, Shanghai Food and Drug Administration, Shanghai, China
| | - Hongcheng Shi
- Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, Shanghai, China
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Gatidis S, Beyer T, Becker M, Riklund K, Nikolaou K, Cyran C, Pfannenberg C. State of affairs of hybrid imaging in Europe: two multi-national surveys from 2017. Insights Imaging 2019; 10:57. [PMID: 31115706 PMCID: PMC6529476 DOI: 10.1186/s13244-019-0741-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 04/04/2019] [Indexed: 01/09/2023] Open
Abstract
OBJECTIVES To assess the current state of hybrid imaging in Europe with respect to operations, reading and reporting, as well as qualification and training. METHODS The first survey (LOCAL) was sent to the heads of the departments of radiology and nuclear medicine in Europe in 2017, including 15 questions regarding the organisation of hybrid imaging operations, reporting strategies for PET/CT and the existence of relevant training programmes. The second survey (NATIONAL) consisted of 10 questions and was directed to the national ministries of health of 37 European countries addressing combined training options in radiology and nuclear medicine. RESULTS In the LOCAL survey, 61 valid responses from 26 European countries were received. In almost half of the institutions, hybrid imaging was performed within a single department, mainly in nuclear medicine departments (31%). In half of the centres (51%), PET/CT reports were performed jointly, while in 20% of the centres, reporting was performed by nuclear medicine physicians. Radiologists were responsible for presenting hybrid imaging results in clinical boards in 34% of responding sites. Integrated hybrid imaging training was available in 41% sites. In the NATIONAL survey, responses from 34 countries were received and demonstrated a heterogeneous landscape of official training possibilities in radiology and nuclear medicine with limited opportunities for additional qualifications in hybrid imaging. CONCLUSIONS The results of these surveys demonstrate a notable heterogeneity in the current practice of hybrid imaging throughout Europe. This heterogeneity exists despite the general consensus that strong professional cooperation is required in order to ensure high clinical quality and to strengthen the clinical role of hybrid imaging.
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Affiliation(s)
- Sergios Gatidis
- Department of Radiology, University Hospital Tübingen, 72076, Tübingen, Germany.
| | - Thomas Beyer
- QIMP Team, Center for Medical Physics and Biomedical Engineering, Medical University Vienna, Vienna, Austria
| | - Minerva Becker
- Department of Radiology and Medical Informatics, University Hospital Geneva, Geneva, Switzerland
| | - Katrine Riklund
- Department of Radiology, Radiation Sciences, Umeå University, 901 85, Umeå, Sweden
| | - Konstantin Nikolaou
- Department of Radiology, University Hospital Tübingen, 72076, Tübingen, Germany
| | - Clemens Cyran
- Department of Radiology, University Hospital, LMU Munich, Marchioninistr. 15, 81377, Munich, Germany
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García-Figueiras R, Baleato-González S, Padhani AR, Luna-Alcalá A, Vallejo-Casas JA, Sala E, Vilanova JC, Koh DM, Herranz-Carnero M, Vargas HA. How clinical imaging can assess cancer biology. Insights Imaging 2019; 10:28. [PMID: 30830470 PMCID: PMC6399375 DOI: 10.1186/s13244-019-0703-0] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 11/08/2018] [Indexed: 02/07/2023] Open
Abstract
Human cancers represent complex structures, which display substantial inter- and intratumor heterogeneity in their genetic expression and phenotypic features. However, cancers usually exhibit characteristic structural, physiologic, and molecular features and display specific biological capabilities named hallmarks. Many of these tumor traits are imageable through different imaging techniques. Imaging is able to spatially map key cancer features and tumor heterogeneity improving tumor diagnosis, characterization, and management. This paper aims to summarize the current and emerging applications of imaging in tumor biology assessment.
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Affiliation(s)
- Roberto García-Figueiras
- Department of Radiology, Hospital Clínico Universitario de Santiago de Compostela, Choupana s/n, 15706, Santiago de Compostela, Spain.
| | - Sandra Baleato-González
- Department of Radiology, Hospital Clínico Universitario de Santiago de Compostela, Choupana s/n, 15706, Santiago de Compostela, Spain
| | - Anwar R Padhani
- Paul Strickland Scanner Centre, Mount Vernon Cancer Centre, Northwood, Middlesex, England, HA6 2RN, UK
| | - Antonio Luna-Alcalá
- Department of Radiology, University Hospitals of Cleveland, Case Western Reserve University, Cleveland, OH, USA
- MRI Unit, Clínica Las Nieves, Health Time, Jaén, Spain
| | - Juan Antonio Vallejo-Casas
- Unidad de Gestión Clínica de Medicina Nuclear. IMIBIC. Hospital Reina Sofía. Universidad de Córdoba, Córdoba, Spain
| | - Evis Sala
- Department of Radiology and Cancer Research UK Cambridge Center, Cambridge, CB2 0QQ, UK
| | - Joan C Vilanova
- Department of Radiology, Clínica Girona and IDI, Lorenzana 36, 17002, Girona, Spain
| | - Dow-Mu Koh
- Department of Radiology, Royal Marsden Hospital & Institute of Cancer Research, Fulham Road, London, SW3 6JJ, UK
| | - Michel Herranz-Carnero
- Nuclear Medicine Department, Hospital Clínico Universitario de Santiago de Compostela, Choupana s/n, 15706, Santiago de Compostela, Galicia, Spain
- Molecular Imaging Program, IDIS, USC, Santiago de Compostela, Galicia, Spain
| | - Herbert Alberto Vargas
- Department of Radiology, Memorial Sloan-Kettering Cancer Center, Radiology, 1275 York Av. Radiology Academic Offices C-278, New York, NY, 10065, USA
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Prato FS, Pavlosky WF, Foster SC, Thiessen JD, Beaujot RP. Screening for Dementia Caused by Modifiable Lifestyle Choices Using Hybrid PET/MRI. J Alzheimers Dis Rep 2019; 3:31-45. [PMID: 30842996 PMCID: PMC6400112 DOI: 10.3233/adr-180098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/19/2018] [Indexed: 12/19/2022] Open
Abstract
Significant advances in positron emission tomography (PET) and magnetic resonance imaging (MRI) brain imaging in the early detection of dementia indicate that hybrid PET/MRI would be an effective tool to screen for dementia in the population living with lifestyle risk factors. Here we investigate the associated costs and benefits along with the needed imaging infrastructure. A demographic analysis determined the prevalence of dementia and its incidence. The expected value of the screening program was calculated assuming a sensitivity and specificity of 0.9, a prevalence of 0.1, a QALY factor of 0.348, a willingness to pay $114,000 CAD and the cost per PET/MRI scan of $2,000 CAD. It was assumed that each head PET/MRI could screen 3,000 individuals per year. The prevalence of dementia is increasing by almost two-fold every 20 years due to the increased population at ages where dementia is more prevalent. It has been shown that a five-year delay in the incidence of dementia would decrease the prevalence by some 45%. In Canada, a five-year delay corresponds to a health care savings of $27,000 CAD per subject per year. The expected value for screening was estimated at $23,745 CAD. The number of subjects to be screened per year in Canada, USA, and China between 60 and 79 was 11,405,000. The corresponding number of head-only hybrid PET/MRI systems needed is 3,800. A brain PET/MRI screening program is financially justifiable with respect to health care costs and justifies the continuing development of MRI compatible brain PET technology.
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Affiliation(s)
- Frank S. Prato
- Department of Medical Biophysics, Western University, London, ON, Canada
- Lawson Health Research Institute, London, ON, Canada
- Department of Medical Imaging, Western University, London, ON, Canada
| | - William F. Pavlosky
- Lawson Health Research Institute, London, ON, Canada
- Department of Medical Imaging, Western University, London, ON, Canada
| | | | - Jonathan D. Thiessen
- Department of Medical Biophysics, Western University, London, ON, Canada
- Lawson Health Research Institute, London, ON, Canada
- Department of Medical Imaging, Western University, London, ON, Canada
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Law I, Albert NL, Arbizu J, Boellaard R, Drzezga A, Galldiks N, la Fougère C, Langen KJ, Lopci E, Lowe V, McConathy J, Quick HH, Sattler B, Schuster DM, Tonn JC, Weller M. Joint EANM/EANO/RANO practice guidelines/SNMMI procedure standards for imaging of gliomas using PET with radiolabelled amino acids and [ 18F]FDG: version 1.0. Eur J Nucl Med Mol Imaging 2018; 46:540-557. [PMID: 30519867 PMCID: PMC6351513 DOI: 10.1007/s00259-018-4207-9] [Citation(s) in RCA: 298] [Impact Index Per Article: 49.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 10/29/2018] [Indexed: 01/12/2023]
Abstract
These joint practice guidelines, or procedure standards, were developed collaboratively by the European Association of Nuclear Medicine (EANM), the Society of Nuclear Medicine and Molecular Imaging (SNMMI), the European Association of Neurooncology (EANO), and the working group for Response Assessment in Neurooncology with PET (PET-RANO). Brain PET imaging is being increasingly used to supplement MRI in the clinical management of glioma. The aim of these standards/guidelines is to assist nuclear medicine practitioners in recommending, performing, interpreting and reporting the results of brain PET imaging in patients with glioma to achieve a high-quality imaging standard for PET using FDG and the radiolabelled amino acids MET, FET and FDOPA. This will help promote the appropriate use of PET imaging and contribute to evidence-based medicine that may improve the diagnostic impact of this technique in neurooncological practice. The present document replaces a former version of the guidelines published in 2006 (Vander Borght et al. Eur J Nucl Med Mol Imaging. 33:1374–80, 2006), and supplements a recent evidence-based recommendation by the PET-RANO working group and EANO on the clinical use of PET imaging in patients with glioma (Albert et al. Neuro Oncol. 18:1199–208, 2016). The information provided should be taken in the context of local conditions and regulations.
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Affiliation(s)
- Ian Law
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, University of Copenhagen, 9, Blegdamsvej, 2100-DK, Copenhagen Ø, Denmark.
| | - Nathalie L Albert
- Department of Nuclear Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Javier Arbizu
- Department of Nuclear Medicine, Clínica Universidad de Navarra, University of Navarre, Pamplona, Spain
| | - Ronald Boellaard
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, Groningen, The Netherlands.,Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands
| | - Alexander Drzezga
- Department of Nuclear Medicine, University Hospital Cologne, Cologne, Germany
| | - Norbert Galldiks
- Department of Neurology, University Hospital Cologne, Cologne, Germany.,Institute of Neuroscience and Medicine (INM-3, -4), Forschungszentrum Julich, Julich, Germany
| | - Christian la Fougère
- Division of Nuclear Medicine and Clinical Molecular Imaging, Department of Radiology, University of Tübingen, Tübingen, Germany
| | - Karl-Josef Langen
- Institute of Neuroscience and Medicine (INM-3, -4), Forschungszentrum Julich, Julich, Germany.,Department of Nuclear Medicine, RWTH University Aachen, Aachen, Germany
| | - Egesta Lopci
- Department of Nuclear Medicine, Humanitas Clinical and Research Hospital, Rozzano, Italy
| | - Val Lowe
- Department of Radiology, Nuclear Medicine, Mayo Clinic, Rochester, MN, USA
| | - Jonathan McConathy
- Division of Molecular Imaging and Therapeutics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Harald H Quick
- High-Field and Hybrid MR Imaging, University Hospital Essen, Essen, Germany
| | - Bernhard Sattler
- Department for Nuclear Medicine, University Hospital Leipzig, Leipzig, Germany
| | - David M Schuster
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, USA
| | - Jörg-Christian Tonn
- Department of Neurosurgery, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Michael Weller
- Department of Neurology, University Hospital Zurich, Zurich, Switzerland
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Mayer KE, Mall S, Yusufi N, Gosmann D, Steiger K, Russelli L, Bianchi HDO, Audehm S, Wagner R, Bräunlein E, Stelzl A, Bassermann F, Weichert W, Weber W, Schwaiger M, D'Alessandria C, Krackhardt AM. T-cell functionality testing is highly relevant to developing novel immuno-tracers monitoring T cells in the context of immunotherapies and revealed CD7 as an attractive target. Am J Cancer Res 2018; 8:6070-6087. [PMID: 30613283 PMCID: PMC6299443 DOI: 10.7150/thno.27275] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 10/14/2018] [Indexed: 12/16/2022] Open
Abstract
Cancer immunotherapy has proven high efficacy in treating diverse cancer entities by immune checkpoint modulation and adoptive T-cell transfer. However, patterns of treatment response differ substantially from conventional therapies, and reliable surrogate markers are missing for early detection of responders versus non-responders. Current imaging techniques using 18F-fluorodeoxyglucose-positron-emmission-tomograpy (18F-FDG-PET) cannot discriminate, at early treatment times, between tumor progression and inflammation. Therefore, direct imaging of T cells at the tumor site represents a highly attractive tool to evaluate effective tumor rejection or evasion. Moreover, such markers may be suitable for theranostic imaging. Methods: We mainly investigated the potential of two novel pan T-cell markers, CD2 and CD7, for T-cell tracking by immuno-PET imaging. Respective antibody- and F(ab´)2 fragment-based tracers were produced and characterized, focusing on functional in vitro and in vivo T-cell analyses to exclude any impact of T-cell targeting on cell survival and antitumor efficacy. Results: T cells incubated with anti-CD2 and anti-CD7 F(ab´)2 showed no major modulation of functionality in vitro, and PET imaging provided a distinct and strong signal at the tumor site using the respective zirconium-89-labeled radiotracers. However, while T-cell tracking by anti-CD7 F(ab´)2 had no long-term impact on T-cell functionality in vivo, anti-CD2 F(ab´)2 caused severe T-cell depletion and failure of tumor rejection. Conclusion: This study stresses the importance of extended functional T-cell assays for T-cell tracer development in cancer immunotherapy imaging and proposes CD7 as a highly suitable target for T-cell immuno-PET imaging.
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Abstract
OBJECTIVE The purpose of this article is to provide an update on clinical PET/MRI, including current and developing clinical indications and technical developments. CONCLUSION PET/MRI is evolving rapidly, transitioning from a predominant research focus to exciting clinical practice. Key technical obstacles have been overcome, and further technical advances promise to herald significant advancements in image quality. Further optimization of protocols to address challenges posed by this hybrid modality will ensure the long-term success of PET/MRI.
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Catana C, Quick HH, Zaidi H. Current commercial techniques for MRI-guided attenuation correction are insufficient and will limit the wider acceptance of PET/MRI technology in the clinic. Med Phys 2018; 45:4007-4010. [PMID: 29758089 DOI: 10.1002/mp.12963] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 05/03/2018] [Indexed: 01/18/2023] Open
Affiliation(s)
- Ciprian Catana
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Harald H Quick
- Erwin L. Hahn Institute for Magnetic Resonance Imaging, University of Duisburg-Essen, Essen, Germany
- High Field and Hybrid MR Imaging, University of Duisburg-Essen, Essen, Germany
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Beyer T, Hicks R, Brun C, Antoch G, Freudenberg LS. An international survey on hybrid imaging: do technology advances preempt our training and education efforts? Cancer Imaging 2018; 18:15. [PMID: 29695290 PMCID: PMC5922309 DOI: 10.1186/s40644-018-0148-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Accepted: 04/13/2018] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Hybrid PET/CT and PET/MRI are increasingly important technologies in the evaluation of malignancy and require cooperation between radiologists and specialists in molecular imaging. The aim of our study was to probe the mindsets of radiological and nuclear medicine professionals in regard to current hybrid imaging practice and to assess relevant training aspirations and perceived shortfalls, particularly amongst young professionals. In this context, we initiated an international survey on "Hybrid Imaging Training". METHODS An online survey was prepared on-line and launched on October-2, 2016. It was composed of 17 multiple-choice and open questions regarding the professional background, a perspective on hybrid imaging training efforts and lessons to be learned from disparate craft groups. The survey ran for 2 weeks. We report total responses per category and individual free-text responses. RESULTS In total, 248 responses were collected with a mean age of all responders of (41 ± 11) y. Overall, 36% were within the target age range of (20-35) y. Across all responders, the majority (72%) commented on there being too few hybrid imaging experts in their country, whereas only 1% said that there were too many. Three quarters of the responders were in favour of a curriculum allowing sub-specialisation in hybrid imaging. With respect to reporting of hybrid imaging, confidence increased with age. The average rating across all responders on the level of cooperation among the two specialties suggested a low overall level of satisfaction. However, the survey feedback indicated the local (on-site) cooperation being somewhat better than the perceived cooperation between the relevant associations on a European level. CONCLUSION We consider these results to represent an appropriate cross-section of professional opinions of imaging experts across different demographic and hierarchical levels. Collectively they provide evidence supporting a need to address current shortfalls in developing hybrid imaging expertise through national educational plans, and, thus, contribute to helping improve patient care.
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Affiliation(s)
- T Beyer
- QIMP Group, Centre Medical Physics and Biomedical Engineering, Medical University Vienna, Währinger Str 18-20/4L, 1090, Vienna, Austria.
| | - R Hicks
- The Sir Peter MacCallum Department of Oncology, the University of Melbourne, Melbourne, 3000, Australia
| | - C Brun
- European Society for Hybrid Medical Imaging, Neutorgasse 10, 1010, Vienna, Austria
| | - G Antoch
- Department of Diagnostic and Interventional Radiology, University Düsseldorf, Medical Faculty, Moorenstrasse 5, 40225, Düsseldorf, Germany
| | - L S Freudenberg
- ZRN Rheinland, Ueberseite 88, 41352, Korschenbroich, Germany
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Abstract
Over the last decade, the combination of PET and MRI in one system has proven to be highly successful in basic preclinical research, as well as in clinical research. Nowadays, PET/MRI systems are well established in preclinical imaging and are progressing into clinical applications to provide further insights into specific diseases, therapeutic assessments, and biological pathways. Certain challenges in terms of hardware had to be resolved concurrently with the development of new techniques to be able to reach the full potential of both combined techniques. This review provides an overview of these challenges and describes the opportunities that simultaneous PET/MRI systems can exploit in comparison with stand-alone or other combined hybrid systems. New approaches were developed for simultaneous PET/MRI systems to correct for attenuation of 511 keV photons because MRI does not provide direct information on gamma photon attenuation properties. Furthermore, new algorithms to correct for motion were developed, because MRI can accurately detect motion with high temporal resolution. The additional information gained by the MRI can be employed to correct for partial volume effects as well. The development of new detector designs in combination with fast-decaying scintillator crystal materials enabled time-of-flight detection and incorporation in the reconstruction algorithms. Furthermore, this review lists the currently commercially available systems both for preclinical and clinical imaging and provides an overview of applications in both fields. In this regard, special emphasis has been placed on data analysis and the potential for both modalities to evolve with advanced image analysis tools, such as cluster analysis and machine learning.
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Affiliation(s)
- Julia G Mannheim
- Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Andreas M Schmid
- Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Johannes Schwenck
- Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University Tuebingen, Tuebingen, Germany; Department of Nuclear Medicine and Clinical Molecular Imaging, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Prateek Katiyar
- Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Kristina Herfert
- Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Bernd J Pichler
- Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University Tuebingen, Tuebingen, Germany.
| | - Jonathan A Disselhorst
- Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University Tuebingen, Tuebingen, Germany
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Beyer T, Hicks RJ, Freudenberg LS. Life is not black and white, nor just Shades of Gray. Eur J Nucl Med Mol Imaging 2018; 45:816-821. [PMID: 29423530 DOI: 10.1007/s00259-018-3943-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 01/05/2018] [Indexed: 12/17/2022]
Affiliation(s)
- T Beyer
- QIMP Group, Centre Medical Physics and Biomedical Engineering, Medical University Vienna, Währinger Str 18-20/4L, 1090, Vienna, Austria.
| | - R J Hicks
- The Sir Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne, 3000, Australia
| | - L S Freudenberg
- ZRN Rheinland, Ueberseite 88, 41352, Korschenbroich, Germany
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Affiliation(s)
- Greg M Pontone
- a Department of Psychiatry and Behavioral Sciences , Johns Hopkins University School of Medicine , Baltimore , MD , USA.,b Department of Neurology , Johns Hopkins University School of Medicine , Baltimore , MD , USA
| | - Kelly A Mills
- b Department of Neurology , Johns Hopkins University School of Medicine , Baltimore , MD , USA
| | - Gwenn S Smith
- a Department of Psychiatry and Behavioral Sciences , Johns Hopkins University School of Medicine , Baltimore , MD , USA.,c Russell H. Morgan Department of Radiology and Radiological Sciences , Johns Hopkins University School of Medicine , Baltimore , MD , USA
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