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Li C, Buch S, Sun Z, Muccio M, Jiang L, Chen Y, Haacke EM, Zhang J, Wisniewski TM, Ge Y. In vivo mapping of hippocampal venous vasculature and oxygenation using susceptibility imaging at 7T. Neuroimage 2024; 291:120597. [PMID: 38554779 PMCID: PMC11115460 DOI: 10.1016/j.neuroimage.2024.120597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 03/19/2024] [Accepted: 03/28/2024] [Indexed: 04/02/2024] Open
Abstract
Mapping the small venous vasculature of the hippocampus in vivo is crucial for understanding how functional changes of hippocampus evolve with age. Oxygen utilization in the hippocampus could serve as a sensitive biomarker for early degenerative changes, surpassing hippocampal tissue atrophy as the main source of information regarding tissue degeneration. Using an ultrahigh field (7T) susceptibility-weighted imaging (SWI) sequence, it is possible to capture oxygen-level dependent contrast of submillimeter-sized vessels. Moreover, the quantitative susceptibility mapping (QSM) results derived from SWI data allow for the simultaneous estimation of venous oxygenation levels, thereby enhancing the understanding of hippocampal function. In this study, we proposed two potential imaging markers in a cohort of 19 healthy volunteers aged between 20 and 74 years. These markers were: 1) hippocampal venous density on SWI images and 2) venous susceptibility (Δχvein) in the hippocampus-associated draining veins (the inferior ventricular veins (IVV) and the basal veins of Rosenthal (BVR) using QSM images). They were chosen specifically to help characterize the oxygen utilization of the human hippocampus and medial temporal lobe (MTL). As part of the analysis, we demonstrated the feasibility of measuring hippocampal venous density and Δχvein in the IVV and BVR at 7T with high spatial resolution (0.25 × 0.25 × 1 mm3). Our results demonstrated the in vivo reconstruction of the hippocampal venous system, providing initial evidence regarding the presence of the venous arch structure within the hippocampus. Furthermore, we evaluated the age effect of the two quantitative estimates and observed a significant increase in Δχvein for the IVV with age (p=0.006, r2 = 0.369). This may suggest the potential application of Δχvein in IVV as a marker for assessing changes in atrophy-related hippocampal oxygen utilization in normal aging and neurodegenerative diseases such as AD and dementia.
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Affiliation(s)
- Chenyang Li
- Department of Radiology, Center for Biomedical Imaging, NYU Grossman School of Medicine, New York, NY, USA; Vilcek Institute of Graduate Biomedical Sciences, NYU Grossman School of Medicine, New York, NY, USA
| | - Sagar Buch
- Department of Neurology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Zhe Sun
- Department of Radiology, Center for Biomedical Imaging, NYU Grossman School of Medicine, New York, NY, USA; Vilcek Institute of Graduate Biomedical Sciences, NYU Grossman School of Medicine, New York, NY, USA
| | - Marco Muccio
- Department of Radiology, Center for Biomedical Imaging, NYU Grossman School of Medicine, New York, NY, USA
| | - Li Jiang
- Department of Radiology, Center for Biomedical Imaging, NYU Grossman School of Medicine, New York, NY, USA
| | - Yongsheng Chen
- Department of Neurology, Wayne State University School of Medicine, Detroit, MI, USA
| | - E Mark Haacke
- Department of Neurology, Wayne State University School of Medicine, Detroit, MI, USA; Department of Radiology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Jiangyang Zhang
- Department of Radiology, Center for Biomedical Imaging, NYU Grossman School of Medicine, New York, NY, USA
| | | | - Yulin Ge
- Department of Radiology, Center for Biomedical Imaging, NYU Grossman School of Medicine, New York, NY, USA.
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Jiang D, Lu H. Cerebral oxygen extraction fraction MRI: Techniques and applications. Magn Reson Med 2022; 88:575-600. [PMID: 35510696 PMCID: PMC9233013 DOI: 10.1002/mrm.29272] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/20/2022] [Accepted: 03/29/2022] [Indexed: 12/20/2022]
Abstract
The human brain constitutes 2% of the body's total mass but uses 20% of the oxygen. The rate of the brain's oxygen utilization can be derived from a knowledge of cerebral blood flow and the oxygen extraction fraction (OEF). Therefore, OEF is a key physiological parameter of the brain's function and metabolism. OEF has been suggested to be a useful biomarker in a number of brain diseases. With recent advances in MRI techniques, several MRI-based methods have been developed to measure OEF in the human brain. These MRI OEF techniques are based on the T2 of blood, the blood signal phase, the magnetic susceptibility of blood-containing voxels, the effect of deoxyhemoglobin on signal behavior in extravascular tissue, and the calibration of the BOLD signal using gas inhalation. Compared to 15 O PET, which is considered the "gold standard" for OEF measurement, MRI-based techniques are non-invasive, radiation-free, and are more widely available. This article provides a review of these emerging MRI-based OEF techniques. We first briefly introduce the role of OEF in brain oxygen homeostasis. We then review the methodological aspects of different categories of MRI OEF techniques, including their signal mechanisms, acquisition methods, and data analyses. The strengths and limitations of the techniques are discussed. Finally, we review key applications of these techniques in physiological and pathological conditions.
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Affiliation(s)
- Dengrong Jiang
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Hanzhang Lu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, Maryland, USA
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3
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Gozt A, Hellewell S, Ward PGD, Bynevelt M, Fitzgerald M. Emerging Applications for Quantitative Susceptibility Mapping in the Detection of Traumatic Brain Injury Pathology. Neuroscience 2021; 467:218-236. [PMID: 34087394 DOI: 10.1016/j.neuroscience.2021.05.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 05/24/2021] [Accepted: 05/25/2021] [Indexed: 12/16/2022]
Abstract
Traumatic brain injury (TBI) is a common but heterogeneous injury underpinned by numerous complex and interrelated pathophysiological mechanisms. An essential trace element, iron is abundant within the brain and involved in many fundamental neurobiological processes, including oxygen transportation, oxidative phosphorylation, myelin production and maintenance, as well as neurotransmitter synthesis and metabolism. Excessive levels of iron are neurotoxic and thus iron homeostasis is tightly regulated in the brain, however, many details about the mechanisms by which this is achieved are yet to be elucidated. A key mediator of oxidative stress, mitochondrial dysfunction and neuroinflammatory response, iron dysregulation is an important contributor to secondary injury in TBI. Advances in neuroimaging that leverage magnetic susceptibility properties have enabled increasingly comprehensive investigations into the distribution and behaviour of iron in the brain amongst healthy individuals as well as disease states such as TBI. Quantitative Susceptibility Mapping (QSM) is an advanced neuroimaging technique that promises quantitative estimation of local magnetic susceptibility at the voxel level. In this review, we provide an overview of brain iron and its homeostasis, describe recent advances enabling applications of QSM within the context of TBI and summarise the current state of the literature. Although limited, the emergent research suggests that QSM is a promising neuroimaging technique that can be used to investigate a host of pathophysiological changes that are associated with TBI.
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Affiliation(s)
- Aleksandra Gozt
- Curtin University, Faculty of Health Sciences, Curtin Health Innovation Research Institute, Bentley, WA Australia; Perron Institute for Neurological and Translational Science, Nedlands, WA Australia
| | - Sarah Hellewell
- Curtin University, Faculty of Health Sciences, Curtin Health Innovation Research Institute, Bentley, WA Australia
| | - Phillip G D Ward
- Australian Research Council Centre of Excellence for Integrative Brain Function, VIC Australia; Turner Institute for Brain and Mental Health, Monash University, VIC Australia
| | - Michael Bynevelt
- Neurological Intervention and Imaging Service of Western Australia, Sir Charles Gairdner Hospital, Nedlands, WA Australia
| | - Melinda Fitzgerald
- Curtin University, Faculty of Health Sciences, Curtin Health Innovation Research Institute, Bentley, WA Australia; Perron Institute for Neurological and Translational Science, Nedlands, WA Australia.
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Chai C, Wang H, Chu Z, Li J, Qian T, Mark Haacke E, Xia S, Shen W. Reduced regional cerebral venous oxygen saturation is a risk factor for the cognitive impairment in hemodialysis patients: a quantitative susceptibility mapping study. Brain Imaging Behav 2021; 14:1339-1349. [PMID: 30511117 DOI: 10.1007/s11682-018-9999-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The purpose of this study was to noninvasively evaluate the changes of regional cerebral venous oxygen saturation (rSvO2) in hemodialysis patients using quantitative susceptibility mapping (QSM) and investigate the relationship with clinical risk factors and neuropsychological testing. Fifty four (54) hemodialysis patients and 54 age, gender and education matched healthy controls (HCs) were recruited in this prospective study. QSM data were reconstructed from the original phase data of susceptibility weighted imaging to measure the susceptibility of cerebral regional major veins in all subjects and calculate their rSvO2. The differences in rSvO2 between hemodialysis patients and HCs were investigated using analysis of covariance adjusting for age and gender as covariates. Stepwise multiple regression and correlation analysis were performed between the cerebral rSvO2 and clinical factors including neuropsychological testing. The SvO2 of the bilateral cortical, thalamostriate, septal, cerebral internal and basal veins in hemodialysis patients was significantly lower than that in HCs (p < 0.001, Bonferroni corrected). The cerebral rSvO2 in all these veins was reduced by 1.67% to 2.30%. The hematocrit, iron, glucose, pre-and post-dialysis diastolic blood pressure (DBP) were independent predictive factors for the cerebral rSvO2 (all P < 0.05). The Mini-Mental State Examination and Montreal Cognitive Assessment (MoCA) scores were both lower in patients than those in HCs (both P < 0.05). The SvO2 of the left cerebral internal vein correlated with MoCA scores (r = 0.492; P = 0.02, FDR corrected). In conclusion, our study indicated that the cerebral rSvO2 was reduced in hemodialysis patients, which was the risk factor for neurocognitive impairment. The hematocrit, iron, glucose, pre-and post-dialysis DBP were independent risk factors for the cerebral rSvO2.
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Affiliation(s)
- Chao Chai
- Department of Radiology, Tianjin First Central Hospital, Tianjin, 300192, China
| | - Huiying Wang
- School of Graduates, Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, China
| | - Zhiqiang Chu
- Department of Hemodialysis, Tianjin First Central Hospital, Tianjin, 300192, China
| | - Jinping Li
- Department of Hemodialysis, Tianjin First Central Hospital, Tianjin, 300192, China
| | - Tianyi Qian
- MR collaboration, Siemens Healthcare, Northeast Asia, Beijing, 100102, China
| | - E Mark Haacke
- Department of Radiology, Wayne State University, Detroit, MI, 48202, USA
| | - Shuang Xia
- Department of Radiology, Tianjin First Central Hospital, Tianjin, 300192, China.
| | - Wen Shen
- Department of Radiology, Tianjin First Central Hospital, Tianjin, 300192, China.
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McFadden JJ, Matthews JC, Scott LA, Parker GJM, Lohézic M, Parkes LM. Optimization of quantitative susceptibility mapping for regional estimation of oxygen extraction fraction in the brain. Magn Reson Med 2021; 86:1314-1329. [PMID: 33780045 DOI: 10.1002/mrm.28789] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 03/05/2021] [Accepted: 03/08/2021] [Indexed: 01/20/2023]
Abstract
PURPOSE We sought to determine the degree to which oxygen extraction fraction (OEF) estimated using quantitative susceptibility mapping (QSM) depends on two critical acquisition parameters that have a significant impact on acquisition time: voxel size and final echo time. METHODS Four healthy volunteers were imaged using a range of isotropic voxel sizes and final echo times. The 0.7 mm data were downsampled at different stages of QSM processing by a factor of 2 (to 1.4 mm), 3 (2.1 mm), or 4 (2.8 mm) to determine the impact of voxel size on each analysis step. OEF was estimated from 11 veins of varying diameter. Inter- and intra-session repeatability were estimated for the optimal protocol by repeat scanning in 10 participants. RESULTS Final echo time was found to have no significant effect on OEF. The effect of voxel size was significant, with larger voxel sizes underestimating OEF, depending on the proximity of the vein to the superficial surface of the brain and on vein diameter. The last analysis step of estimating vein OEF values from susceptibility images had the largest dependency on voxel size. Inter-session coefficients of variation on OEF estimates of between 5.2% and 8.7% are reported, depending on the vein. CONCLUSION QSM acquisition times can be minimized by reducing the final echo time but an isotropic voxel size no larger than 1 mm is needed to accurately estimate OEF in most medium/large veins in the brain. Such acquisitions can be achieved in under 4 min.
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Affiliation(s)
- John J McFadden
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, Faculty of Biology, Medicine, and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Julian C Matthews
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, Faculty of Biology, Medicine, and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Lauren A Scott
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, Faculty of Biology, Medicine, and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Geoff J M Parker
- Bioxydyn Limited, Manchester, United Kingdom.,Centre for Medical Image Computing, Department of Computer Science and Department of Neuroinflammation, University College London, London, United Kingdom
| | - Maélène Lohézic
- Applications & Workflow, GE Healthcare, Manchester, United Kingdom
| | - Laura M Parkes
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, Faculty of Biology, Medicine, and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom.,Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, Manchester, United Kingdom
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6
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Fan AP, Khalil AA, Fiebach JB, Zaharchuk G, Villringer A, Villringer K, Gauthier CJ. Elevated brain oxygen extraction fraction measured by MRI susceptibility relates to perfusion status in acute ischemic stroke. J Cereb Blood Flow Metab 2020; 40:539-551. [PMID: 30732551 PMCID: PMC7026852 DOI: 10.1177/0271678x19827944] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Recent clinical trials of new revascularization therapies in acute ischemic stroke have highlighted the importance of physiological imaging to identify optimal treatments for patients. Oxygen extraction fraction (OEF) is a hallmark of at-risk tissue in stroke, and can be quantified from the susceptibility effect of deoxyhemoglobin molecules in venous blood on MRI phase scans. We measured OEF within cerebral veins using advanced quantitative susceptibility mapping (QSM) MRI reconstructions in 20 acute stroke patients. Absolute OEF was elevated in the affected (29.3 ± 3.4%) versus the contralateral hemisphere (25.5 ± 3.1%) of patients with large diffusion-perfusion lesion mismatch (P = 0.032). In these patients, OEF negatively correlated with relative CBF measured by dynamic susceptibility contrast MRI (P = 0.004), suggesting compensation for reduced flow. Patients with perfusion-diffusion match or no hypo-perfusion showed less OEF difference between hemispheres. Nine patients received longitudinal assessment and showed OEF ratio (affected to contralateral) of 1.2 ± 0.1 at baseline that normalized (decreased) to 1.0 ± 0.1 at follow-up three days later (P = 0.03). Our feasibility study demonstrates that QSM MRI can non-invasively quantify OEF in stroke patients, relates to perfusion status, and is sensitive to OEF changes over time. Clinical trial registration: Longitudinal MRI examinations of patients with brain ischemia and blood brain barrier permeability; clinicaltrials.org :NCT02077582.
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Affiliation(s)
- Audrey P Fan
- Department of Radiology, Stanford University, Stanford, CA, USA
| | - Ahmed A Khalil
- Center for Stroke Research Berlin, Charité Universitätsmedizin Berlin, Berlin, Germany.,Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.,Berlin School of Mind and Brain, Humboldt-Universitaet zu Berlin, Berlin, Germany
| | - Jochen B Fiebach
- Center for Stroke Research Berlin, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Greg Zaharchuk
- Department of Radiology, Stanford University, Stanford, CA, USA
| | - Arno Villringer
- Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.,Berlin School of Mind and Brain, Humboldt-Universitaet zu Berlin, Berlin, Germany
| | - Kersten Villringer
- Center for Stroke Research Berlin, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Claudine J Gauthier
- Department of Physics, Concordia University, Montreal, Canada.,Montreal Heart Institute, Montreal, Canada
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7
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Biondetti E, Rojas-Villabona A, Sokolska M, Pizzini FB, Jäger HR, Thomas DL, Shmueli K. Investigating the oxygenation of brain arteriovenous malformations using quantitative susceptibility mapping. Neuroimage 2019; 199:440-453. [DOI: 10.1016/j.neuroimage.2019.05.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 04/23/2019] [Accepted: 05/06/2019] [Indexed: 02/07/2023] Open
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Turk EA, Stout JN, Ha C, Luo J, Gagoski B, Yetisir F, Golland P, Wald LL, Adalsteinsson E, Robinson JN, Roberts DJ, Barth WH, Grant PE. Placental MRI: Developing Accurate Quantitative Measures of Oxygenation. Top Magn Reson Imaging 2019; 28:285-297. [PMID: 31592995 PMCID: PMC7323862 DOI: 10.1097/rmr.0000000000000221] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The Human Placenta Project has focused attention on the need for noninvasive magnetic resonance imaging (MRI)-based techniques to diagnose and monitor placental function throughout pregnancy. The hope is that the management of placenta-related pathologies would be improved if physicians had more direct, real-time measures of placental health to guide clinical decision making. As oxygen alters signal intensity on MRI and oxygen transport is a key function of the placenta, many of the MRI methods under development are focused on quantifying oxygen transport or oxygen content of the placenta. For example, measurements from blood oxygen level-dependent imaging of the placenta during maternal hyperoxia correspond to outcomes in twin pregnancies, suggesting that some aspects of placental oxygen transport can be monitored by MRI. Additional methods are being developed to accurately quantify baseline placental oxygenation by MRI relaxometry. However, direct validation of placental MRI methods is challenging and therefore animal studies and ex vivo studies of human placentas are needed. Here we provide an overview of the current state of the art of oxygen transport and quantification with MRI. We suggest that as these techniques are being developed, increased focus be placed on ensuring they are robust and reliable across individuals and standardized to enable predictive diagnostic models to be generated from the data. The field is still several years away from establishing the clinical benefit of monitoring placental function in real time with MRI, but the promise of individual personalized diagnosis and monitoring of placental disease in real time continues to motivate this effort.
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Affiliation(s)
- Esra Abaci Turk
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children’s Hospital, MA, USA
| | - Jeffrey N. Stout
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children’s Hospital, MA, USA
| | - Christopher Ha
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children’s Hospital, MA, USA
| | - Jie Luo
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Borjan Gagoski
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children’s Hospital, MA, USA
| | - Filiz Yetisir
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children’s Hospital, MA, USA
| | - Polina Golland
- Computer Science and Artificial Intelligence Laboratory (CSAIL), Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Lawrence L. Wald
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Elfar Adalsteinsson
- Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology, Cambridge, MA, United States
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Julian N. Robinson
- Department of Obstetrics and Gynecology, Brigham and Women’s Hospital, Boston, USA
| | | | - William H. Barth
- Maternal-Fetal Medicine, Obstetrics and Gynecology, Massachusetts General Hospital, Boston, MA, USA
| | - P. Ellen Grant
- Fetal-Neonatal Neuroimaging & Developmental Science Center, Boston Children’s Hospital, MA, USA
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Decreased susceptibility of major veins in mild traumatic brain injury is correlated with post-concussive symptoms: A quantitative susceptibility mapping study. NEUROIMAGE-CLINICAL 2017; 15:625-632. [PMID: 28664033 PMCID: PMC5479969 DOI: 10.1016/j.nicl.2017.06.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 06/04/2017] [Accepted: 06/07/2017] [Indexed: 01/28/2023]
Abstract
Cerebral venous oxygen saturation (SvO2) is an important biomarker of brain function. In this study, we aimed to explore the relative changes of regional cerebral SvO2 among axonal injury (AI) patients, non-AI patients and healthy controls (HCs) using quantitative susceptibility mapping (QSM). 48 patients and 32 HCs were enrolled. The patients were divided into two groups depending on the imaging based evidence of AI. QSM was used to measure the susceptibility of major cerebral veins. Nonparametric testing was performed for susceptibility differences among the non-AI patient group, AI patient group and healthy control group. Correlation was performed between the susceptibility of major cerebral veins, elapsed time post trauma (ETPT) and post-concussive symptom scores. The ROC analysis was performed for the diagnostic efficiency of susceptibility to discriminate mTBI patients from HCs. The susceptibility of the straight sinus in non-AI and AI patients was significantly lower than that in HCs (P < 0.001, P = 0.004, respectively, Bonferroni corrected), which may indicate an increased regional cerebral SvO2 in patients. The susceptibility of the straight sinus in non-AI patients positively correlated with ETPT (r = 0.573, P = 0.003, FDR corrected) while that in AI patients negatively correlated with the Rivermead Post Concussion Symptoms Questionnaire scores (r = − 0.582, P = 0.018, FDR corrected). The sensitivity, specificity and AUC values of susceptibility for the discrimination between mTBI patients and HCs were 88%, 69% and 0.84. In conclusion, the susceptibility of the straight sinus can be used as a biomarker to monitor the progress of mild TBI and to differentiate mTBI patients from healthy controls. Mild traumatic brain injury caused decreased venous susceptibility. The venous susceptibility can discriminate mTBI patients from healthy controls. Decreased susceptibility may indicate increased venous oxygen saturation (SvO2). Increased SvO2 of patients without axonal injury decreased with time post-injury. Increased SvO2 of axonal injury patients indicated severe post-concussive symptoms.
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10
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Ward PGD, Fan AP, Raniga P, Barnes DG, Dowe DL, Ng ACL, Egan GF. Improved Quantification of Cerebral Vein Oxygenation Using Partial Volume Correction. Front Neurosci 2017; 11:89. [PMID: 28289372 PMCID: PMC5326785 DOI: 10.3389/fnins.2017.00089] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 02/10/2017] [Indexed: 11/25/2022] Open
Abstract
Purpose: Quantitative susceptibility mapping (QSM) enables cerebral venous characterization and physiological measurements, such as oxygen extraction fraction (OEF). The exquisite sensitivity of QSM to deoxygenated blood makes it possible to image small veins; however partial volume effects must be addressed for accurate quantification. We present a new method, Iterative Cylindrical Fitting (ICF), to estimate voxel-based partial volume effects for susceptibility maps and use it to improve OEF quantification of small veins with diameters between 1.5 and 4 voxels. Materials and Methods: Simulated QSM maps were generated to assess the performance of the ICF method over a range of vein geometries with varying echo times and noise levels. The ICF method was also applied to in vivo human brain data to assess the feasibility and behavior of OEF measurements compared to the maximum intensity voxel (MIV) method. Results: Improved quantification of OEF measurements was achieved for vessels with contrast to noise greater than 3.0 and vein radii greater than 0.75 voxels. The ICF method produced improved quantitative accuracy of OEF measurement compared to the MIV approach (mean OEF error 7.7 vs. 12.4%). The ICF method provided estimates of vein radius (mean error <27%) and partial volume maps (root mean-squared error <13%). In vivo results demonstrated consistent estimates of OEF along vein segments. Conclusion: OEF quantification in small veins (1.5–4 voxels in diameter) had lower error when using partial volume estimates from the ICF method.
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Affiliation(s)
- Phillip G D Ward
- Monash Biomedical Imaging, Monash UniversityClayton, VIC, Australia; Faculty of Information Technology, Monash UniversityClayton, VIC, Australia
| | - Audrey P Fan
- Department of Radiology, Lucas Center for Imaging, Stanford University Stanford, CA, USA
| | - Parnesh Raniga
- Monash Biomedical Imaging, Monash UniversityClayton, VIC, Australia; The Australian eHealth Research Centre, CSIRO Health and BiosecurityHerston, QLD, Australia
| | - David G Barnes
- Faculty of Information Technology, Monash UniversityClayton, VIC, Australia; Monash eResearch Centre, Monash UniversityClayton, VIC, Australia
| | - David L Dowe
- Faculty of Information Technology, Monash University Clayton, VIC, Australia
| | - Amanda C L Ng
- Department of Anatomy and Neuroscience, The University of Melbourne Melbourne, VIC, Australia
| | - Gary F Egan
- Monash Biomedical Imaging, Monash UniversityClayton, VIC, Australia; ARC Centre of Excellence for Integrative Brain FunctionMelbourne, VIC, Australia
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