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Cagol A, Tsagkas C, Granziera C. Advanced Brain Imaging in Central Nervous System Demyelinating Diseases. Neuroimaging Clin N Am 2024; 34:335-357. [PMID: 38942520 DOI: 10.1016/j.nic.2024.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/30/2024]
Abstract
In recent decades, advances in neuroimaging have profoundly transformed our comprehension of central nervous system demyelinating diseases. Remarkable technological progress has enabled the integration of cutting-edge acquisition and postprocessing techniques, proving instrumental in characterizing subtle focal changes, diffuse microstructural alterations, and macroscopic pathologic processes. This review delves into state-of-the-art modalities applied to multiple sclerosis, neuromyelitis optica spectrum disorders, and myelin oligodendrocyte glycoprotein antibody-associated disease. Furthermore, it explores how this dynamic landscape holds significant promise for the development of effective and personalized clinical management strategies, encompassing support for differential diagnosis, prognosis, monitoring treatment response, and patient stratification.
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Affiliation(s)
- Alessandro Cagol
- Translational Imaging in Neurology (ThINk) Basel, Department of Biomedical Engineering, University Hospital Basel and University of Basel, Hegenheimermattweg 167b, 4123 Allschwil, Switzerland; Department of Neurology, University Hospital Basel, Petersgraben 4, 4031 Basel, Switzerland; Research Center for Clinical Neuroimmunology and Neuroscience Basel (RC2NB), University Hospital Basel and University of Basel, Spitalstrasse 2, 4031 Basel, Switzerland; Department of Health Sciences, University of Genova, Via A. Pastore, 1 16132 Genova, Italy. https://twitter.com/CagolAlessandr0
| | - Charidimos Tsagkas
- Translational Imaging in Neurology (ThINk) Basel, Department of Biomedical Engineering, University Hospital Basel and University of Basel, Hegenheimermattweg 167b, 4123 Allschwil, Switzerland; Translational Neuroradiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), 10 Center Drive, Bethesda, MD 20892, USA
| | - Cristina Granziera
- Translational Imaging in Neurology (ThINk) Basel, Department of Biomedical Engineering, University Hospital Basel and University of Basel, Hegenheimermattweg 167b, 4123 Allschwil, Switzerland; Department of Neurology, University Hospital Basel, Petersgraben 4, 4031 Basel, Switzerland; Research Center for Clinical Neuroimmunology and Neuroscience Basel (RC2NB), University Hospital Basel and University of Basel, Spitalstrasse 2, 4031 Basel, Switzerland.
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2
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Baas KPA, Everard AJ, Körver S, van Dussen L, Coolen BF, Strijkers GJ, Hollak CEM, Nederveen AJ. Progressive Changes in Cerebral Apparent Diffusion Values in Fabry Disease: A 5-Year Follow-up MRI Study. AJNR Am J Neuroradiol 2023; 44:1157-1164. [PMID: 37770205 PMCID: PMC10549936 DOI: 10.3174/ajnr.a8001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 08/16/2023] [Indexed: 10/03/2023]
Abstract
BACKGROUND AND PURPOSE White matter lesions are commonly found in patients with Fabry disease. Existing studies have shown elevated diffusivity in healthy-appearing brain regions that are commonly associated with white matter lesions, suggesting that DWI could help detect white matter lesions at an earlier stage This study explores whether diffusivity changes precede white matter lesion formation in a cohort of patients with Fabry disease undergoing yearly MR imaging examinations during a 5-year period. MATERIALS AND METHODS T1-weighted anatomic, FLAIR, and DWI scans of 48 patients with Fabry disease (23 women; median age, 44 years; range, 15-69 years) were retrospectively included. White matter lesions and tissue probability maps were segmented and, together with ADC maps, were transformed into standard space. ADC values were determined within lesions before and after detection on FLAIR images and compared with normal-appearing white matter ADC. By means of linear mixed-effects modeling, changes in ADC and ΔADC (relative to normal-appearing white matter) across time were investigated. RESULTS ADC was significantly higher within white matter lesions compared with normal-appearing white matter (P < .01), even before detection on FLAIR images. ADC and ΔADC were significantly affected by sex, showing higher values in men (60.1 [95% CI, 23.8-96.3] ×10-6mm2/s and 35.1 [95% CI, 6.0-64.2] ×10-6mm2/s), respectively. ΔADC increased faster in men compared with women (0.99 [95% CI, 0.27-1.71] ×10-6mm2/s/month). ΔADC increased with time even when only considering data from before detection (0.57 [95% CI, 0.01-1.14] ×10-6mm2/s/month). CONCLUSIONS Our results indicate that in Fabry disease, changes in diffusion precede the formation of white matter lesions and that microstructural changes progress faster in men compared with women. These findings suggest that DWI may be of predictive value for white matter lesion formation in Fabry disease.
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Affiliation(s)
- Koen P A Baas
- From the Department of Radiology and Nuclear Medicine (K.P.A.B., A.J.N.), Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
| | - Albert J Everard
- Faculty of Science (A.J.E.), Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Simon Körver
- Department of Endocrinology and Metabolism (S.K., L.v.D., C.E.M.H.), Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
| | - Laura van Dussen
- Department of Endocrinology and Metabolism (S.K., L.v.D., C.E.M.H.), Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
| | - Bram F Coolen
- Department of Biomedical Engineering and Physics (B.F.C., G.J.S.), Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
- Amsterdam Cardiovascular Sciences (B.F.C., G.J.S.), University of Amsterdam, Amsterdam, the Netherlands
| | - Gustav J Strijkers
- Department of Biomedical Engineering and Physics (B.F.C., G.J.S.), Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
- Amsterdam Cardiovascular Sciences (B.F.C., G.J.S.), University of Amsterdam, Amsterdam, the Netherlands
| | - Carla E M Hollak
- Department of Endocrinology and Metabolism (S.K., L.v.D., C.E.M.H.), Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
| | - Aart J Nederveen
- From the Department of Radiology and Nuclear Medicine (K.P.A.B., A.J.N.), Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
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3
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Ellen O, Ye S, Nheu D, Dass M, Pagnin M, Ozturk E, Theotokis P, Grigoriadis N, Petratos S. The Heterogeneous Multiple Sclerosis Lesion: How Can We Assess and Modify a Degenerating Lesion? Int J Mol Sci 2023; 24:11112. [PMID: 37446290 DOI: 10.3390/ijms241311112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 06/21/2023] [Accepted: 06/30/2023] [Indexed: 07/15/2023] Open
Abstract
Multiple sclerosis (MS) is a heterogeneous disease of the central nervous system that is governed by neural tissue loss and dystrophy during its progressive phase, with complex reactive pathological cellular changes. The immune-mediated mechanisms that promulgate the demyelinating lesions during relapses of acute episodes are not characteristic of chronic lesions during progressive MS. This has limited our capacity to target the disease effectively as it evolves within the central nervous system white and gray matter, thereby leaving neurologists without effective options to manage individuals as they transition to a secondary progressive phase. The current review highlights the molecular and cellular sequelae that have been identified as cooperating with and/or contributing to neurodegeneration that characterizes individuals with progressive forms of MS. We emphasize the need for appropriate monitoring via known and novel molecular and imaging biomarkers that can accurately detect and predict progression for the purposes of newly designed clinical trials that can demonstrate the efficacy of neuroprotection and potentially neurorepair. To achieve neurorepair, we focus on the modifications required in the reactive cellular and extracellular milieu in order to enable endogenous cell growth as well as transplanted cells that can integrate and/or renew the degenerative MS plaque.
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Affiliation(s)
- Olivia Ellen
- Department of Neuroscience, Central Clinical School, Monash University, Melborune, VIC 3004, Australia
| | - Sining Ye
- Department of Neuroscience, Central Clinical School, Monash University, Melborune, VIC 3004, Australia
| | - Danica Nheu
- Department of Neuroscience, Central Clinical School, Monash University, Melborune, VIC 3004, Australia
| | - Mary Dass
- Department of Neuroscience, Central Clinical School, Monash University, Melborune, VIC 3004, Australia
| | - Maurice Pagnin
- Department of Neuroscience, Central Clinical School, Monash University, Melborune, VIC 3004, Australia
| | - Ezgi Ozturk
- Department of Neuroscience, Central Clinical School, Monash University, Melborune, VIC 3004, Australia
| | - Paschalis Theotokis
- Laboratory of Experimental Neurology and Neuroimmunology, Department of Neurology, AHEPA University Hospital, Stilponos Kiriakides Str. 1, 54636 Thessaloniki, Greece
| | - Nikolaos Grigoriadis
- Laboratory of Experimental Neurology and Neuroimmunology, Department of Neurology, AHEPA University Hospital, Stilponos Kiriakides Str. 1, 54636 Thessaloniki, Greece
| | - Steven Petratos
- Department of Neuroscience, Central Clinical School, Monash University, Melborune, VIC 3004, Australia
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Oost W, Huitema AJ, Kats K, Giepmans BNG, Kooistra SM, Eggen BJL, Baron W. Pathological ultrastructural alterations of myelinated axons in normal appearing white matter in progressive multiple sclerosis. Acta Neuropathol Commun 2023; 11:100. [PMID: 37340488 DOI: 10.1186/s40478-023-01598-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 06/02/2023] [Indexed: 06/22/2023] Open
Abstract
Multiple sclerosis (MS) pathophysiology includes inflammation, demyelination and neurodegeneration, but the exact mechanisms of disease initiation and progression are unknown. A major feature of lesions is lack of myelin, which increases axonal energy demand and requires adaptation in number and size of mitochondria. Outside lesions, subtle and diffuse alterations are observed in normal appearing white matter (NAWM) and normal appearing grey matter (NAGM), including increased oxidative stress, reduced axon density and changes in myelin composition and morphology. On an ultrastructural level, only limited data is available on alterations in myelinated axons. We generated large scale 2D scanning transmission electron microscopy images ('nanotomy') of non-demyelinated brain tissue of control and progressive MS donors, accessible via an open-access online repository. We observed a reduced density of myelinated axons in NAWM, without a decrease in cross-sectional axon area. Small myelinated axons were less frequently and large myelinated axons were more frequently present in NAWM, while the g-ratio was similar. The correlation between axonal mitochondrial radius and g-ratio was lost in NAWM, but not in NAGM. Myelinated axons in control GM and NAGM had a similar g-ratio and radius distribution. We hypothesize that axonal loss in NAWM is likely compensated by swelling of the remaining myelinated axons and subsequent adjustment of myelin thickness to maintain their g-ratio. Failure of axonal mitochondria to adjust their size and fine-tuning of myelin thickness may render NAWM axons and their myelin more susceptible to injury.
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Affiliation(s)
- Wendy Oost
- Department of Biomedical Sciences of Cells and Systems, Section Molecular Neurobiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
- MS Center Noord Nederland, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Allard J Huitema
- Department of Biomedical Sciences of Cells and Systems, Section Molecular Neurobiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
- MS Center Noord Nederland, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Kim Kats
- Department of Biomedical Sciences of Cells and Systems, Section Molecular Neurobiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Ben N G Giepmans
- Department of Biomedical Sciences of Cells and Systems, Section Molecular Neurobiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Susanne M Kooistra
- Department of Biomedical Sciences of Cells and Systems, Section Molecular Neurobiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
- MS Center Noord Nederland, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Bart J L Eggen
- Department of Biomedical Sciences of Cells and Systems, Section Molecular Neurobiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
- MS Center Noord Nederland, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Wia Baron
- Department of Biomedical Sciences of Cells and Systems, Section Molecular Neurobiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
- MS Center Noord Nederland, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
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Periventricular magnetisation transfer abnormalities in early multiple sclerosis. Neuroimage Clin 2022; 34:103012. [PMID: 35487133 PMCID: PMC9125781 DOI: 10.1016/j.nicl.2022.103012] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 04/14/2022] [Accepted: 04/18/2022] [Indexed: 11/30/2022]
Abstract
Periventricular-MTR gradients are present from the earliest stage of MS and become steeper in advanced disease. Lower MTR in periventricular-NAWM was positively associated with reduced cortical-mean-thickness. MTR in periventricular-lesions scaled with cortical-mean-thickness, while non-periventricular lesions were unrelated. These findings suggest a common pathophysiologic mechanism between CSF-adjacent cortical and periventricular areas.
Objective Recent studies suggested that CSF-mediated factors contribute to periventricular (PV) T2-hyperintense lesion formation in multiple sclerosis (MS) and this in turn correlates with cortical damage. We thus investigated if such PV-changes are observable microstructurally in early-MS and if they correlate with cortical damage. Methods We assessed the magnetisation transfer ratio (MTR) in PV normal-appearing white matter (NAWM) and in MS lesions in 44 patients with a clinically isolated syndrome (CIS) suggestive of MS and 73 relapsing-remitting MS (RRMS) patients. Band-wise MTR values were related to cortical mean thickness (CMT) and compared with 49 healthy controls (HCs). For each band, MTR changes were assessed relative to the average MTR values of all HCs. Results Relative to HCs, PV-MTR was significantly reduced up to 2.63% in CIS and 5.37% in RRMS (p < 0.0001). The MTR decreased towards the lateral ventricles with 0.18%/mm in CIS and 0.31%/mm in RRMS patients, relative to HCs. In RRMS, MTR-values adjacent to the ventricle and in PV-lesions correlated positively with CMT and negatively with EDSS. Conclusion PV-MTR gradients are present from the earliest stage of MS, consistent with more pronounced microstructural WM-damage closer to the ventricles. The positive association between reduced CMT and lower MTR in PV-NAWM suggests a common pathophysiologic mechanism. Together, these findings indicate the potential use of multimodal MRI as refined marker for MS-related tissue changes.
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York EN, Thrippleton MJ, Meijboom R, Hunt DPJ, Waldman AD. Quantitative magnetization transfer imaging in relapsing-remitting multiple sclerosis: a systematic review and meta-analysis. Brain Commun 2022; 4:fcac088. [PMID: 35652121 PMCID: PMC9149789 DOI: 10.1093/braincomms/fcac088] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 12/17/2021] [Accepted: 03/31/2022] [Indexed: 11/28/2022] Open
Abstract
Myelin-sensitive MRI such as magnetization transfer imaging has been widely used in multiple sclerosis. The influence of methodology and differences in disease subtype on imaging findings is, however, not well established. Here, we systematically review magnetization transfer brain imaging findings in relapsing-remitting multiple sclerosis. We examine how methodological differences, disease effects and their interaction influence magnetization transfer imaging measures. Articles published before 06/01/2021 were retrieved from online databases (PubMed, EMBASE and Web of Science) with search terms including 'magnetization transfer' and 'brain' for systematic review, according to a pre-defined protocol. Only studies that used human in vivo quantitative magnetization transfer imaging in adults with relapsing-remitting multiple sclerosis (with or without healthy controls) were included. Additional data from relapsing-remitting multiple sclerosis subjects acquired in other studies comprising mixed disease subtypes were included in meta-analyses. Data including sample size, MRI acquisition protocol parameters, treatments and clinical findings were extracted and qualitatively synthesized. Where possible, effect sizes were calculated for meta-analyses to determine magnetization transfer (i) differences between patients and healthy controls; (ii) longitudinal change and (iii) relationships with clinical disability in relapsing-remitting multiple sclerosis. Eighty-six studies met inclusion criteria. MRI acquisition parameters varied widely, and were also underreported. The majority of studies examined the magnetization transfer ratio in white matter, but magnetization transfer metrics, brain regions examined and results were heterogeneous. The analysis demonstrated a risk of bias due to selective reporting and small sample sizes. The pooled random-effects meta-analysis across all brain compartments revealed magnetization transfer ratio was 1.17 per cent units (95% CI -1.42 to -0.91) lower in relapsing-remitting multiple sclerosis than healthy controls (z-value: -8.99, P < 0.001, 46 studies). Linear mixed-model analysis did not show a significant longitudinal change in magnetization transfer ratio across all brain regions [β = 0.12 (-0.56 to 0.80), t-value = 0.35, P = 0.724, 14 studies] or normal-appearing white matter alone [β = 0.037 (-0.14 to 0.22), t-value = 0.41, P = 0.68, eight studies]. There was a significant negative association between the magnetization transfer ratio and clinical disability, as assessed by the Expanded Disability Status Scale [r = -0.32 (95% CI -0.46 to -0.17); z-value = -4.33, P < 0.001, 13 studies]. Evidence suggests that magnetization transfer imaging metrics are sensitive to pathological brain changes in relapsing-remitting multiple sclerosis, although effect sizes were small in comparison to inter-study variability. Recommendations include: better harmonized magnetization transfer acquisition protocols with detailed methodological reporting standards; larger, well-phenotyped cohorts, including healthy controls; and, further exploration of techniques such as magnetization transfer saturation or inhomogeneous magnetization transfer ratio.
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Affiliation(s)
- Elizabeth N. York
- Centre for Clinical Brain Sciences, University of
Edinburgh, Edinburgh, UK
| | | | - Rozanna Meijboom
- Centre for Clinical Brain Sciences, University of
Edinburgh, Edinburgh, UK
| | - David P. J. Hunt
- Centre for Clinical Brain Sciences, University of
Edinburgh, Edinburgh, UK
- UK Dementia Research Institute, University of
Edinburgh, Edinburgh, UK
- Anne Rowling Regenerative Neurology Clinic,
University of Edinburgh, Edinburgh, UK
| | - Adam D. Waldman
- Centre for Clinical Brain Sciences, University of
Edinburgh, Edinburgh, UK
- UK Dementia Research Institute, University of
Edinburgh, Edinburgh, UK
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7
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Hashem M, Shafqat Q, Wu Y, Rho JM, Dunn JF. Abnormal Oxidative Metabolism in the Cuprizone Mouse Model of Demyelination: an in vivo NIRS-MRI Study. Neuroimage 2022; 250:118935. [PMID: 35091079 DOI: 10.1016/j.neuroimage.2022.118935] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 01/19/2022] [Accepted: 01/24/2022] [Indexed: 12/11/2022] Open
Abstract
Disruptions in oxidative metabolism may occur in multiple sclerosis and other demyelinating neurological diseases. The impact of demyelination on metabolic rate is also not understood. It is possible that mitochondrial damage may be associated with many such neurological disorders. To study oxidative metabolism with one model of demyelination, we implemented a novel multimodal imaging technique combining Near-Infrared Spectroscopy (NIRS) and MRI to cuprizone mouse model. The cuprizone model is used to study demyelination and may be associated with inhibition of mitochondrial function. Cuprizone mice showed reduced oxygen extraction fraction (-39.1%, p≤0.001), increased tissue oxygenation (6.4%, p≤0.001), and reduced cerebral metabolic rate of oxygen in cortical gray matter (-62.1%, p≤0.001). These changes resolved after the cessation of cuprizone exposure and partial remyelination. A decrease in hemoglobin concentration (-34.4%, p≤0.001), but no change in cerebral blood flow were also observed during demyelination. The oxidized state of the mitochondrial enzyme, Cytochrome C Oxidase (CCO) increased (46.3%, p≤0.001) while the reduced state decreased (-34.4%, p≤0.05) significantly in cuprizone mice. The total amount of CCO did not change significantly during cuprizone exposure. Total CCO did decline after recovery both in control (-23.1%, p≤0.01) and cuprizone (-28.8%, p≤0.001) groups which may relate to age. A reduction in the magnetization transfer ratio, indicating demyelination, was found in the cuprizone group in the cerebral cortex (-3.2%, p≤0.01) and corpus callosum (-5.5%, p≤0.001). In summary, we were able to detect evidence of altered CCO metabolism during cuprizone exposure, consistent with a mitochondrial defect. We observed increased oxygenation and reduced metabolic rate associated with reduced myelination in the gray and white matter. The novel multimodal imaging technique applied here shows promise for noninvasively assessing parameters associated with oxidative metabolism in both mouse models of neurological disease and for translation to study oxidative metabolism in the human brain.
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Affiliation(s)
- Mada Hashem
- Biomedical Engineering Graduate Program, University of Calgary, Calgary, Alberta, Canada T2N 4N1; Department of Radiology, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada, T2N 4N1; Hotchkiss Brain Institute, University of Calgary, Alberta, Canada, T2N 4N1; Experimental Imaging Centre, Cumming School of Medicine, University of Calgary, Alberta, Canada, T2N 4N1
| | - Qandeel Shafqat
- Department of Radiology, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada, T2N 4N1; Hotchkiss Brain Institute, University of Calgary, Alberta, Canada, T2N 4N1; Experimental Imaging Centre, Cumming School of Medicine, University of Calgary, Alberta, Canada, T2N 4N1
| | - Ying Wu
- Department of Radiology, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada, T2N 4N1; Hotchkiss Brain Institute, University of Calgary, Alberta, Canada, T2N 4N1; Experimental Imaging Centre, Cumming School of Medicine, University of Calgary, Alberta, Canada, T2N 4N1
| | - Jong M Rho
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Alberta, Canada, T2N 4N1
| | - Jeff F Dunn
- Department of Radiology, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada, T2N 4N1; Hotchkiss Brain Institute, University of Calgary, Alberta, Canada, T2N 4N1; Experimental Imaging Centre, Cumming School of Medicine, University of Calgary, Alberta, Canada, T2N 4N1.
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8
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Cairns J, Vavasour IM, Traboulsee A, Carruthers R, Kolind SH, Li DKB, Moore GRW, Laule C. Diffusely abnormal white matter in multiple sclerosis. J Neuroimaging 2021; 32:5-16. [PMID: 34752664 DOI: 10.1111/jon.12945] [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: 10/08/2021] [Revised: 10/17/2021] [Accepted: 10/18/2021] [Indexed: 02/06/2023] Open
Abstract
MRI enables detailed in vivo depiction of multiple sclerosis (MS) pathology. Localized areas of MS damage, commonly referred to as lesions, or plaques, have been a focus of clinical and research MRI studies for over four decades. A nonplaque MRI abnormality which is present in at least 25% of MS patients but has received far less attention is diffusely abnormal white matter (DAWM). DAWM has poorly defined boundaries and a signal intensity that is between normal-appearing white matter and classic lesions on proton density and T2 -weighted images. All clinical phenotypes of MS demonstrate DAWM, including clinically isolated syndrome, where DAWM is associated with higher lesion volume, reduced brain volume, and earlier conversion to MS. Advanced MRI metric abnormalities in DAWM tend to be greater than those in NAWM, but not as severe as focal lesions, with myelin, axons, and water-related changes commonly reported. Histological studies demonstrate a primary lipid abnormality in DAWM, with some axonal damage and lesser involvement of myelin proteins. This review provides an overview of DAWM identification, summarizes in vivo and postmortem observations, and comments on potential pathophysiological mechanisms, which may underlie DAWM in MS. Given the prevalence and potential clinical impact of DAWM, the number of imaging studies focusing on DAWM is insufficient. Characterization of DAWM significance and microstructure would benefit from larger longitudinal and additional quantitative imaging efforts. Revisiting data from previous studies that included proton density and T2 imaging would enable retrospective DAWM identification and analysis.
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Affiliation(s)
- James Cairns
- Department of Medicine (Neurology), University of British Columbia, British Columbia, Vancouver, Canada.,Department of Radiology, University of British Columbia, British Columbia, Vancouver, Canada
| | - Irene M Vavasour
- Department of Radiology, University of British Columbia, British Columbia, Vancouver, Canada.,International Collaboration on Repair Discoveries, Blusson Spinal Cord Centre, University of British Columbia, British Columbia, Vancouver, Canada
| | - Anthony Traboulsee
- Department of Medicine (Neurology), University of British Columbia, British Columbia, Vancouver, Canada
| | - Robert Carruthers
- Department of Medicine (Neurology), University of British Columbia, British Columbia, Vancouver, Canada
| | - Shannon H Kolind
- Department of Medicine (Neurology), University of British Columbia, British Columbia, Vancouver, Canada.,Department of Radiology, University of British Columbia, British Columbia, Vancouver, Canada.,International Collaboration on Repair Discoveries, Blusson Spinal Cord Centre, University of British Columbia, British Columbia, Vancouver, Canada.,Department of Physics & Astronomy, University of British Columbia, British Columbia, Vancouver, Canada
| | - David K B Li
- Department of Medicine (Neurology), University of British Columbia, British Columbia, Vancouver, Canada.,Department of Radiology, University of British Columbia, British Columbia, Vancouver, Canada
| | - G R Wayne Moore
- Department of Medicine (Neurology), University of British Columbia, British Columbia, Vancouver, Canada.,International Collaboration on Repair Discoveries, Blusson Spinal Cord Centre, University of British Columbia, British Columbia, Vancouver, Canada.,Department of Pathology & Laboratory Medicine, University of British Columbia, British Columbia, Vancouver, Canada
| | - Cornelia Laule
- Department of Radiology, University of British Columbia, British Columbia, Vancouver, Canada.,International Collaboration on Repair Discoveries, Blusson Spinal Cord Centre, University of British Columbia, British Columbia, Vancouver, Canada.,Department of Physics & Astronomy, University of British Columbia, British Columbia, Vancouver, Canada.,Department of Pathology & Laboratory Medicine, University of British Columbia, British Columbia, Vancouver, Canada
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9
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Elliott C, Momayyezsiahkal P, Arnold DL, Liu D, Ke J, Zhu L, Zhu B, George IC, Bradley DP, Fisher E, Cahir-McFarland E, Stys PK, Geurts JJG, Franchimont N, Gafson A, Belachew S. Abnormalities in normal-appearing white matter from which multiple sclerosis lesions arise. Brain Commun 2021; 3:fcab176. [PMID: 34557664 PMCID: PMC8453433 DOI: 10.1093/braincomms/fcab176] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 06/08/2021] [Accepted: 06/09/2021] [Indexed: 11/24/2022] Open
Abstract
Normal-appearing white matter is far from normal in multiple sclerosis; little is known about the precise pathology or spatial pattern of this alteration and its relation to subsequent lesion formation. This study was undertaken to evaluate normal-appearing white matter abnormalities in brain areas where multiple sclerosis lesions subsequently form, and to investigate the spatial distribution of normal-appearing white matter abnormalities in persons with multiple sclerosis. Brain MRIs of pre-lesion normal-appearing white matter were analysed in participants with new T2 lesions, pooled from three clinical trials: SYNERGY (NCT01864148; n = 85 with relapsing multiple sclerosis) was the test data set; ASCEND (NCT01416181; n = 154 with secondary progressive multiple sclerosis) and ADVANCE (NCT00906399; n = 261 with relapsing-remitting multiple sclerosis) were used as validation data sets. Focal normal-appearing white matter tissue state was analysed prior to lesion formation in areas where new T2 lesions later formed (pre-lesion normal-appearing white matter) using normalized magnetization transfer ratio and T2-weighted (nT2) intensities, and compared with overall normal-appearing white matter and spatially matched contralateral normal-appearing white matter. Each outcome was analysed using linear mixed-effects models. Follow-up time (as a categorical variable), patient-level characteristics (including treatment group) and other baseline variables were treated as fixed effects. In SYNERGY, nT2 intensity was significantly higher, and normalized magnetization transfer ratio was lower in pre-lesion normal-appearing white matter versus overall and contralateral normal-appearing white matter at all time points up to 24 weeks before new T2 lesion onset. In ASCEND and ADVANCE (for which normalized magnetization transfer ratio was not available), nT2 intensity in pre-lesion normal-appearing white matter was significantly higher compared to both overall and contralateral normal-appearing white matter at all pre-lesion time points extending up to 2 years prior to lesion formation. In all trials, nT2 intensity in the contralateral normal-appearing white matter was also significantly higher at all pre-lesion time points compared to overall normal-appearing white matter. Brain atlases of normal-appearing white matter abnormalities were generated using measures of voxel-wise differences in normalized magnetization transfer ratio of normal-appearing white matter in persons with multiple sclerosis compared to scanner-matched healthy controls. We observed that overall spatial distribution of normal-appearing white matter abnormalities in persons with multiple sclerosis largely recapitulated the anatomical distribution of probabilities of T2 hyperintense lesions. Overall, these findings suggest that intrinsic spatial properties and/or longstanding precursory abnormalities of normal-appearing white matter tissue may contribute to the risk of autoimmune acute demyelination in multiple sclerosis.
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Affiliation(s)
| | - Parya Momayyezsiahkal
- NeuroRx Research, Montreal, QC H2X 3P9, Canada.,McGill University, Montreal, QC H3A 0G4, Canada
| | - Douglas L Arnold
- NeuroRx Research, Montreal, QC H2X 3P9, Canada.,McGill University, Montreal, QC H3A 0G4, Canada
| | - Dawei Liu
- Biogen Digital Health, Biogen, Cambridge, MA 02142, USA
| | - Jun Ke
- Biogen, Cambridge, MA 02142, USA
| | - Li Zhu
- Biogen, Cambridge, MA 02142, USA
| | - Bing Zhu
- Biogen, Cambridge, MA 02142, USA
| | - Ilena C George
- Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA
| | | | | | | | - Peter K Stys
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Jeroen J G Geurts
- Department of Anatomy and Neurosciences, Amsterdam UMC, 1081 HV Amsterdam, Netherlands
| | | | - Arie Gafson
- Biogen Digital Health, Biogen, Cambridge, MA 02142, USA
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10
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Bernitsas E, Kopinsky H, Lichtman-Mikol S, Razmjou S, Santiago-Martinez C, Yarraguntla K, Bao F. Multimodal MRI Response to Fingolimod in Multiple Sclerosis: A Nonrandomized, Single Arm, Observational Study. J Neuroimaging 2020; 31:379-387. [PMID: 33368776 DOI: 10.1111/jon.12824] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 11/22/2020] [Accepted: 11/30/2020] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Fingolimod has a favorable effect on conventional MRI measures; however, its neuroprotective effect is not clear. We aim to investigate changes of conventional and advanced MRI measures in lesions and normal-appearing white matter (NAWM) over 2 years in fingolimod-treated patients. METHODS Fifty relapsing-remitting multiple sclerosis patients and 27 healthy controls were enrolled in the study and underwent baseline, 1-year, and 2-year 3T MRI scans. T2 lesion volume, whole brain volume, cortical gray matter volume, white matter volume, corpus callosum area, percentage brain volume change (PBVC), Expanded Disability Status Scale, gadolinium-enhancing lesions, PBVC, magnetization transfer ratio (MTR), and diffusion tensor imaging metrics (fractional anisotropy [FA] and median diffusivity [MD]) in lesions and NAWM were calculated. Longitudinal changes were examined using one-way repeated measures ANOVA. Bonferroni correction for multiple testing was used when appropriate. RESULTS Conventional MRI measures were unchanged in both groups. Lesion MTR increased significantly (P < .001), but NAWM-MTR remained unchanged. Lesion FA improved significantly in year 1 (P = .003) and over the study duration (P = .05). Lesion MD changed significantly from baseline to year 1 (P < .001) and remained stable over 2 years. NAWM-FA was significant from baseline to year 1 (P = .002) and from baseline to year 2 (P < .001). NAWM-MD was significant only from baseline to year 1 (P = .001). CONCLUSIONS These findings suggest a possible neuroreparative effect of fingolimod on the MS lesions and NAWM. Larger and longer randomized studies are required to confirm these results.
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Affiliation(s)
- Evanthia Bernitsas
- Department of Neurology, Wayne State University School of Medicine, Detroit, MI
| | - Hannah Kopinsky
- Department of Neurology, Wayne State University School of Medicine, Detroit, MI
| | | | - Sarah Razmjou
- Department of Neurology, Wayne State University School of Medicine, Detroit, MI
| | | | - Kalyan Yarraguntla
- Department of Neurology, Wayne State University School of Medicine, Detroit, MI
| | - Fen Bao
- Department of Neurology, Wayne State University School of Medicine, Detroit, MI
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11
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Afshari R, Santini F, Heule R, Meyer CH, Pfeuffer J, Bieri O. One-minute whole-brain magnetization transfer ratio imaging with intrinsic B 1 -correction. Magn Reson Med 2020; 85:2686-2695. [PMID: 33349950 DOI: 10.1002/mrm.28618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 11/03/2020] [Accepted: 11/06/2020] [Indexed: 11/07/2022]
Abstract
PURPOSE Magnetization transfer ratio (MTR) histograms are used widely for the assessment of diffuse pathological changes in the brain. For broad clinical application, MTR scans should not only be fast, but confounding factors should also be minimized for high reproducibility. To this end, a 1-minute whole-brain spiral MTR method with intrinsic B1 -field correction is introduced. METHODS A spiral multislice spoiled gradient-echo sequence with adaptable magnetization-transfer saturation pulses (angle β) is proposed. After a low-resolution single-shot spiral readout and a dummy preparation period, high-resolution images are acquired using an interleaved spiral readout. For whole-brain MTR imaging, 50 interleaved slices with three different magnetization-transfer contrasts (β = 0°, 350°, and 550°) together with an intrinsic B1 -field map are recorded in 58.5 seconds on a clinical 3T system. From the three contrasts, two sets of MTR images are derived and used for subsequent B1 correction, assuming a linear dependency on β. For validation, a binary spin bath model is used. RESULTS For the proposed B1 -correction scheme, numerical simulations indicate for brain tissue a decrease of about a factor of 10 for the B1 -related bias on MTR. As a result, following B1 correction, MTR differences in gray and white matter become markedly accentuated, and the reproducibility of MTR histograms from scan-rescan experiments is improved. Furthermore, B1 -corrected MTR histograms show a lower variability for age-matched normal-appearing brain tissue. CONCLUSION From its speed and offering intrinsic B1 correction, the proposed method shows excellent prospects for clinical studies that explore magnetization-transfer effects based on MTR histogram analysis.
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Affiliation(s)
- Roya Afshari
- Division of Radiological Physics, Department of Radiology, University Hospital Basel, Basel, Switzerland
- Department of Biomedical Engineering, University of Basel, Basel, Switzerland
| | - Francesco Santini
- Division of Radiological Physics, Department of Radiology, University Hospital Basel, Basel, Switzerland
- Department of Biomedical Engineering, University of Basel, Basel, Switzerland
| | - Rahel Heule
- High Field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, Tübingen, Germany
| | - Craig H Meyer
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA
| | - Josef Pfeuffer
- Application Development, Siemens Healthcare, Erlangen, Germany
| | - Oliver Bieri
- Division of Radiological Physics, Department of Radiology, University Hospital Basel, Basel, Switzerland
- Department of Biomedical Engineering, University of Basel, Basel, Switzerland
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12
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Ma YJ, Searleman AC, Jang H, Fan SJ, Wong J, Xue Y, Cai Z, Chang EY, Corey-Bloom J, Du J. Volumetric imaging of myelin in vivo using 3D inversion recovery-prepared ultrashort echo time cones magnetic resonance imaging. NMR IN BIOMEDICINE 2020; 33:e4326. [PMID: 32691472 PMCID: PMC7952008 DOI: 10.1002/nbm.4326] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 03/19/2020] [Accepted: 05/02/2020] [Indexed: 05/28/2023]
Abstract
Direct myelin imaging is promising for characterization of multiple sclerosis (MS) brains at diagnosis and in response to therapy. In this study, a 3D inversion recovery-prepared ultrashort echo time cones (IR-UTE-Cones) sequence was used for both morphological and quantitative imaging of myelin on a clinical 3 T scanner. Myelin powder phantoms with different myelin concentrations were imaged with the 3D UTE-Cones sequence and it showed a strong correlation between concentrations and UTE-Cones signals, demonstrating the ability of the UTE-Cones sequence to directly image myelin in the brain. Quantitative myelin imaging with multi-echo IR-UTE-Cones sequences show similar T2 * values for a D2 O-exchanged myelin phantom (T2 * = 0.33 ± 0.04 ms), ex vivo brain specimens (T2 * = 0.20 ± 0.04 ms) and in vivo healthy volunteers (T2 * = 0.254 ± 0.023 ms), further confirming the feasibility of 3D IR-UTE-Cones sequences for direct myelin imaging in vivo. In ex vivo MS brain study, signal loss is observed in MS lesions, which was confirmed with histology. For the in vivo study, the lesions in MS patients also show myelin signal loss using the proposed direct myelin imaging method, demonstrating the clinical potential for MS diagnosis. Furthermore, the measured IR-UTE-Cones signal intensities show a significant difference between normal-appearing white matter in MS patients and normal white matter in volunteers, which cannot be found in clinical used T2 -FLAIR sequences. Thus, the proposed 3D IR-UTE-Cones sequence showed clinical potential for MS diagnosis with the capability of direct myelin detection of the whole brain.
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Affiliation(s)
- Ya-Jun Ma
- Department of Radiology, University of California San Diego, San Diego, CA, USA
| | - Adam C. Searleman
- Department of Radiology, University of California San Diego, San Diego, CA, USA
| | - Hyungseok Jang
- Department of Radiology, University of California San Diego, San Diego, CA, USA
| | - Shu-Juan Fan
- Department of Radiology, University of California San Diego, San Diego, CA, USA
| | - Jonathan Wong
- Department of Radiology, University of California San Diego, San Diego, CA, USA
- Radiology Service, VA San Diego Healthcare System, San Diego, CA, USA
| | - Yanping Xue
- Department of Radiology, University of California San Diego, San Diego, CA, USA
| | - Zhenyu Cai
- Department of Radiology, University of California San Diego, San Diego, CA, USA
| | - Eric Y. Chang
- Department of Radiology, University of California San Diego, San Diego, CA, USA
- Radiology Service, VA San Diego Healthcare System, San Diego, CA, USA
| | - Jody Corey-Bloom
- Department of Neurosciences, University of California San Diego, San Diego, CA, USA
| | - Jiang Du
- Department of Radiology, University of California San Diego, San Diego, CA, USA
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13
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Ma YJ, Jang H, Wei Z, Cai Z, Xue Y, Lee RR, Chang EY, Bydder GM, Corey-Bloom J, Du J. Myelin Imaging in Human Brain Using a Short Repetition Time Adiabatic Inversion Recovery Prepared Ultrashort Echo Time (STAIR-UTE) MRI Sequence in Multiple Sclerosis. Radiology 2020; 297:392-404. [PMID: 32779970 DOI: 10.1148/radiol.2020200425] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Background Water signal contamination is a major challenge for direct ultrashort echo time (UTE) imaging of myelin in vivo because water contributes most of the signals detected in white matter. Purpose To validate a new short repetition time (TR) adiabatic inversion recovery (STAIR) prepared UTE (STAIR-UTE) sequence designed to suppress water signals and to allow imaging of ultrashort T2 protons of myelin in white matter using a clinical 3-T scanner. Materials and Methods In this prospective study, an optimization framework was used to obtain the optimal inversion time for nulling water signals using STAIR-UTE imaging at different TRs. Numeric simulation and phantom studies were performed. Healthy volunteers and participants with multiple sclerosis (MS) underwent MRI between November 2018 and October 2019 to compare STAIR-UTE and a clinical T2-weighted fluid-attenuated inversion recovery sequence for assessment of MS lesions. UTE measures of myelin were also performed to allow comparison of signals in lesions and with those in normal-appearing white matter (NAWM) in patients with MS and in normal white matter (NWM) in healthy volunteers. Results Simulation and phantom studies both suggest that the proposed STAIR-UTE technique can effectively suppress long T2 tissues with a broad range of T1s. Ten healthy volunteers (mean age, 33 years ± 8 [standard deviation]; six women) and 10 patients with MS (mean age, 51 years ± 16; seven women) were evaluated. The three-dimensional STAIR-UTE sequence effectively suppressed water components in white matter and selectively imaged myelin, which had a measured T2* value of 0.21 msec ± 0.04 in the volunteer study. A much lower mean UTE measure of myelin proton density was found in MS lesions (3.8 mol/L ± 1.5), and a slightly lower mean UTE measure was found in NAWM (7.2 mol/L ± 0.8) compared with that in NWM (8.0 mol/L ± 0.8) in the healthy volunteers (P < .001 for both comparisons). Conclusion The short repetition time adiabatic inversion recovery-prepared ultrashort echo time sequence provided efficient water signal suppression for volumetric imaging of myelin in the brain and showed excellent myelin signal contrast as well as marked ultrashort echo time signal reduction in multiple sclerosis lesions and a smaller reduction in normal-appearing white matter compared with normal white matter in volunteers. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Messina and Port in this issue.
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Affiliation(s)
- Ya-Jun Ma
- From the Departments of Radiology (Y.J.M., H.J., Z.W., Z.C., Y.X., R.R.L., E.Y.C., G.M.B., J.D.) and Neurosciences (J.C.B.) University of California San Diego, 9452 Medical Center Dr, La Jolla, CA 92037; and Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, Calif (E.Y.C.)
| | - Hyungseok Jang
- From the Departments of Radiology (Y.J.M., H.J., Z.W., Z.C., Y.X., R.R.L., E.Y.C., G.M.B., J.D.) and Neurosciences (J.C.B.) University of California San Diego, 9452 Medical Center Dr, La Jolla, CA 92037; and Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, Calif (E.Y.C.)
| | - Zhao Wei
- From the Departments of Radiology (Y.J.M., H.J., Z.W., Z.C., Y.X., R.R.L., E.Y.C., G.M.B., J.D.) and Neurosciences (J.C.B.) University of California San Diego, 9452 Medical Center Dr, La Jolla, CA 92037; and Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, Calif (E.Y.C.)
| | - Zhenyu Cai
- From the Departments of Radiology (Y.J.M., H.J., Z.W., Z.C., Y.X., R.R.L., E.Y.C., G.M.B., J.D.) and Neurosciences (J.C.B.) University of California San Diego, 9452 Medical Center Dr, La Jolla, CA 92037; and Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, Calif (E.Y.C.)
| | - Yanping Xue
- From the Departments of Radiology (Y.J.M., H.J., Z.W., Z.C., Y.X., R.R.L., E.Y.C., G.M.B., J.D.) and Neurosciences (J.C.B.) University of California San Diego, 9452 Medical Center Dr, La Jolla, CA 92037; and Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, Calif (E.Y.C.)
| | - Roland R Lee
- From the Departments of Radiology (Y.J.M., H.J., Z.W., Z.C., Y.X., R.R.L., E.Y.C., G.M.B., J.D.) and Neurosciences (J.C.B.) University of California San Diego, 9452 Medical Center Dr, La Jolla, CA 92037; and Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, Calif (E.Y.C.)
| | - Eric Y Chang
- From the Departments of Radiology (Y.J.M., H.J., Z.W., Z.C., Y.X., R.R.L., E.Y.C., G.M.B., J.D.) and Neurosciences (J.C.B.) University of California San Diego, 9452 Medical Center Dr, La Jolla, CA 92037; and Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, Calif (E.Y.C.)
| | - Graeme M Bydder
- From the Departments of Radiology (Y.J.M., H.J., Z.W., Z.C., Y.X., R.R.L., E.Y.C., G.M.B., J.D.) and Neurosciences (J.C.B.) University of California San Diego, 9452 Medical Center Dr, La Jolla, CA 92037; and Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, Calif (E.Y.C.)
| | - Jody Corey-Bloom
- From the Departments of Radiology (Y.J.M., H.J., Z.W., Z.C., Y.X., R.R.L., E.Y.C., G.M.B., J.D.) and Neurosciences (J.C.B.) University of California San Diego, 9452 Medical Center Dr, La Jolla, CA 92037; and Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, Calif (E.Y.C.)
| | - Jiang Du
- From the Departments of Radiology (Y.J.M., H.J., Z.W., Z.C., Y.X., R.R.L., E.Y.C., G.M.B., J.D.) and Neurosciences (J.C.B.) University of California San Diego, 9452 Medical Center Dr, La Jolla, CA 92037; and Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, Calif (E.Y.C.)
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14
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Zhang L, Wen B, Chen T, Tian H, Xue H, Ren H, Li L, Fan Q, Ren Z. A comparison study of inhomogeneous magnetization transfer (ihMT) and magnetization transfer (MT) in multiple sclerosis based on whole brain acquisition at 3.0 T. Magn Reson Imaging 2020; 70:43-49. [PMID: 32224092 DOI: 10.1016/j.mri.2020.03.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 03/19/2020] [Accepted: 03/25/2020] [Indexed: 11/16/2022]
Abstract
INTRODUCTION Multiple sclerosis (MS) is a central nervous system disorder that may eventually affect its function. The clinical standard for MS severity is based on a clinical scale, which lacks lesion specific information. Magnetic resonance imaging of MS faces the challenge of myelin specificity, and in this work a new method inhomogeneous magnetization transfer (ihMT) is investigated as new biomarker of demyelination in MS. METHODS Local ethics committee approved this study and written informed consents were obtained. Between Oct 2017 to May 2018, eighteen patients with relapsing-remitting MS (RRMS) (6 males, 12 females, mean age 31.2) and sixteen healthy volunteers (6 males, 10 females, mean age 30.4 years) were enrolled in this prospective study. All subjects underwent MRI exams including MT and ihMT imaging as well as the Expanded Disability Status Scale (EDSS) assessments. Independent sample t-test were used to compare the difference of ihMT parameters between healthy white matter (HWM) and normal appearing white matter (NAWM) and between HWM and MS lesions, respectively. Spearman correlation were used to analyze the correlation between ihMT parameters of MS lesions and EDSS score. RESULTS The ihMTR and qihMT demonstrate significant differences between WHM and NAWM groups, while no significant differences are observed for MTR and qMT. All parameters show significant differences between HWM and MS groups (p < 0.05). There was moderate negative correlation between MTR, qMT and EDSS score (-0.440 and -0.572), while there was a strong negative correlation between ihMTR and qihMT and EDSS score (-0.704 and -0.739). CONCLUSION Based on whole brain analysis at 3.0 T, ihMT showed better correlation with EDSS compared to magnetization transfer imaging, and may be a potentially valuable biomarker for demyelination in MS.
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Affiliation(s)
- Lei Zhang
- Department of Radiology, Baoji Center Hospital, Baoji, Shaanxi, People's Republic of China
| | - Baohong Wen
- Department of Radiology, Zhengzhou Univerisity First Affilicated Hospital, Zhengzhou, Henan, People's Republic of China
| | - Tao Chen
- Department of Radiology, Baoji Center Hospital, Baoji, Shaanxi, People's Republic of China
| | - Hongzhe Tian
- Department of Radiology, Baoji Center Hospital, Baoji, Shaanxi, People's Republic of China
| | - Hongqiang Xue
- Department of Radiology, Baoji Center Hospital, Baoji, Shaanxi, People's Republic of China
| | - Huipeng Ren
- Department of Radiology, Baoji Center Hospital, Baoji, Shaanxi, People's Republic of China
| | - Li Li
- Department of Radiology, Baoji Center Hospital, Baoji, Shaanxi, People's Republic of China
| | - Qing Fan
- Department of Radiology, Baoji Center Hospital, Baoji, Shaanxi, People's Republic of China
| | - Zhuanqin Ren
- Department of Radiology, Baoji Center Hospital, Baoji, Shaanxi, People's Republic of China; Department of Medical Techniques, Shaanxi University of Chinese Medicine, Xianyang, 712000, Shannxi, People's Republic of China.
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15
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Rahmanzadeh R, Brück W, Minagar A, Sahraian MA. Multiple sclerosis pathogenesis: missing pieces of an old puzzle. Rev Neurosci 2019; 30:67-83. [PMID: 29883325 DOI: 10.1515/revneuro-2018-0002] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Accepted: 03/30/2018] [Indexed: 11/15/2022]
Abstract
Traditionally, multiple sclerosis (MS) was considered to be a CD4 T cell-mediated CNS autoimmunity, compatible with experimental autoimmune encephalitis model, which can be characterized by focal lesions in the white matter. However, studies of recent decades revealed several missing pieces of MS puzzle and showed that MS pathogenesis is more complex than the traditional view and may include the following: a primary degenerative process (e.g. oligodendroglial pathology), generalized abnormality of normal-appearing brain tissue, pronounced gray matter pathology, involvement of innate immunity, and CD8 T cells and B cells. Here, we review these findings and discuss their implications in MS pathogenesis.
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Affiliation(s)
- Reza Rahmanzadeh
- MS Research Center, Neuroscience Institute, Tehran University of Medical Science, Department of Neurology, Sina Hospital, 1136746911 Tehran, Iran
| | - Wolfgang Brück
- Institute of Neuropathology, University Medical Center, D-37075 Göttingen, Germany
| | - Alireza Minagar
- Department of Neurology, LSU Health Sciences Center, Shreveport, LA 71130, USA
| | - Mohammad Ali Sahraian
- MS Research Center, Neuroscience Institute, Tehran University of Medical Science, Department of Neurology, Sina Hospital, 1136746911 Tehran, Iran.,Iranian Center for Neurological Research, Neuroscience Institute, Tehran University of Medical Science, 1136746890 Tehran, Iran
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16
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O'Muircheartaigh J, Vavasour I, Ljungberg E, Li DKB, Rauscher A, Levesque V, Garren H, Clayton D, Tam R, Traboulsee A, Kolind S. Quantitative neuroimaging measures of myelin in the healthy brain and in multiple sclerosis. Hum Brain Mapp 2019; 40:2104-2116. [PMID: 30648315 PMCID: PMC6590140 DOI: 10.1002/hbm.24510] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 12/28/2018] [Accepted: 01/02/2019] [Indexed: 12/25/2022] Open
Abstract
Quantitative magnetic resonance imaging (MRI) techniques have been developed as imaging biomarkers, aiming to improve the specificity of MRI to underlying pathology compared to conventional weighted MRI. For assessing the integrity of white matter (WM), myelin, in particular, several techniques have been proposed and investigated individually. However, comparisons between these methods are lacking. In this study, we compared four established myelin‐sensitive MRI techniques in 56 patients with relapsing–remitting multiple sclerosis (MS) and 38 healthy controls. We used T2‐relaxation with combined GRadient And Spin Echoes (GRASE) to measure myelin water fraction (MWF‐G), multi‐component driven equilibrium single pulse observation of T1 and T2 (mcDESPOT) to measure MWF‐D, magnetization‐transfer imaging to measure magnetization‐transfer ratio (MTR), and T1 relaxation to measure quantitative T1 (qT1). Using voxelwise Spearman correlations, we tested the correspondence of methods throughout the brain. All four methods showed associations that varied across tissue types; the highest correlations were found between MWF‐D and qT1 (median ρ across tissue classes 0.8) and MWF‐G and MWF‐D (median ρ = 0.59). In eight WM tracts, all measures showed differences (p < 0.05) between MS normal‐appearing WM and healthy control WM, with qT1 showing the highest number of different regions (8), followed by MWF‐D and MTR (6), and MWF‐G (n = 4). Comparing the methods in terms of their statistical sensitivity to MS lesions in WM, MWF‐D demonstrated the best accuracy (p < 0.05, after multiple comparison correction). To aid future power analysis, we provide the average and standard deviation volumes of the four techniques, estimated from the healthy control sample.
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Affiliation(s)
- Jonathan O'Muircheartaigh
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry Psychology and Neuroscience, King's College London, London, United Kingdom.,Centre for the Developing Brain, Department of Perinatal Imaging and Health, St. Thomas' Hospital, King's College London, London, United Kingdom.,Department of Neuroimaging, Institute of Psychiatry Psychology and Neuroscience, King's College London, London, United Kingdom.,MRC Centre for Neurodevelopmental Disorders, King's College London, London, United Kingdom
| | - Irene Vavasour
- Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Emil Ljungberg
- Department of Neuroimaging, Institute of Psychiatry Psychology and Neuroscience, King's College London, London, United Kingdom
| | - David K B Li
- Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada.,MS/MRI Research Group, Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada
| | - Alexander Rauscher
- Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | | | | | | | - Roger Tam
- Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada.,MS/MRI Research Group, Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada.,School of Biomedical Engineering, University of British Columbia, Vancouver, British Columbia, Canada
| | - Anthony Traboulsee
- MS/MRI Research Group, Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada.,Division of Neurology, Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Shannon Kolind
- Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada.,MS/MRI Research Group, Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada.,Division of Neurology, Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
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17
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Laule C, Moore GW. Myelin water imaging to detect demyelination and remyelination and its validation in pathology. Brain Pathol 2018; 28:750-764. [PMID: 30375119 PMCID: PMC8028667 DOI: 10.1111/bpa.12645] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 07/09/2018] [Indexed: 12/11/2022] Open
Abstract
Damage to myelin is a key feature of multiple sclerosis (MS) pathology. Magnetic resonance imaging (MRI) has revolutionized our ability to detect and monitor MS pathology in vivo. Proton density, T1 and T2 can provide qualitative contrast weightings that yield superb in vivo visualization of central nervous system tissue and have proved invaluable as diagnostic and patient management tools in MS. However, standard clinical MR methods are not specific to the types of tissue damage they visualize, and they cannot detect subtle abnormalities in tissue that appears otherwise normal on conventional MRIs. Myelin water imaging is an MR method that provides in vivo measurement of myelin. Histological validation work in both human brain and spinal cord tissue demonstrates a strong correlation between myelin water and staining for myelin, validating myelin water as a marker for myelin. Myelin water varies throughout the brain and spinal cord in healthy controls, and shows good intra- and inter-site reproducibility. MS plaques show variably decreased myelin water fraction, with older lesions demonstrating the greatest myelin loss. Longitudinal study of myelin water can provide insights into the dynamics of demyelination and remyelination in plaques. Normal appearing brain and spinal cord tissues show reduced myelin water, an abnormality which becomes progressively more evident over a timescale of years. Diffusely abnormal white matter, which is evident in 20%-25% of MS patients, also shows reduced myelin water both in vivo and postmortem, and appears to originate from a primary lipid abnormality with relative preservation of myelin proteins. Active research is ongoing in the quest to refine our ability to image myelin and its perturbations in MS and other disorders of the myelin sheath.
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Affiliation(s)
- Cornelia Laule
- RadiologyUniversity of British ColumbiaVancouverBCCanada
- Pathology & Laboratory MedicineUniversity of British ColumbiaVancouverBCCanada
- Physics & AstronomyUniversity of British ColumbiaVancouverBCCanada
- International Collaboration on Repair Discoveries (ICORD)University of British ColumbiaVancouverBCCanada
| | - G.R. Wayne Moore
- Pathology & Laboratory MedicineUniversity of British ColumbiaVancouverBCCanada
- International Collaboration on Repair Discoveries (ICORD)University of British ColumbiaVancouverBCCanada
- Medicine (Neurology)University of British ColumbiaVancouverBCCanada
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18
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Hagiwara A, Hori M, Kamagata K, Warntjes M, Matsuyoshi D, Nakazawa M, Ueda R, Andica C, Koshino S, Maekawa T, Irie R, Takamura T, Kumamaru KK, Abe O, Aoki S. Myelin Measurement: Comparison Between Simultaneous Tissue Relaxometry, Magnetization Transfer Saturation Index, and T 1w/T 2w Ratio Methods. Sci Rep 2018; 8:10554. [PMID: 30002497 PMCID: PMC6043493 DOI: 10.1038/s41598-018-28852-6] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 07/02/2018] [Indexed: 01/06/2023] Open
Abstract
Magnetization transfer (MT) imaging has been widely used for estimating myelin content in the brain. Recently, two other approaches, namely simultaneous tissue relaxometry of R1 and R2 relaxation rates and proton density (SyMRI) and the ratio of T1-weighted to T2-weighted images (T1w/T2w ratio), were also proposed as methods for measuring myelin. SyMRI and MT imaging have been reported to correlate well with actual myelin by histology. However, for T1w/T2w ratio, such evidence is limited. In 20 healthy adults, we examined the correlation between these three methods, using MT saturation index (MTsat) for MT imaging. After calibration, white matter (WM) to gray matter (GM) contrast was the highest for SyMRI among these three metrics. Even though SyMRI and MTsat showed strong correlation in the WM (r = 0.72), only weak correlation was found between T1w/T2w and SyMRI (r = 0.45) or MTsat (r = 0.38) (correlation coefficients significantly different from each other, with p values < 0.001). In subcortical and cortical GM, these measurements showed moderate to strong correlations to each other (r = 0.54 to 0.78). In conclusion, the high correlation between SyMRI and MTsat indicates that both methods are similarly suited to measure myelin in the WM, whereas T1w/T2w ratio may be less optimal.
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Affiliation(s)
- Akifumi Hagiwara
- Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan.
- Department of Radiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
| | - Masaaki Hori
- Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan
| | - Koji Kamagata
- Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan
| | - Marcel Warntjes
- SyntheticMR AB, Linköping, Sweden
- Center for Medical Imaging Science and Visualization (CMIV), Linköping, Sweden
| | - Daisuke Matsuyoshi
- Araya Inc., Tokyo, Japan
- Research Institute for Science and Engineering, Waseda University, Waseda, Japan
- Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Misaki Nakazawa
- Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan
| | - Ryo Ueda
- Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan
- Department of Radiological Sciences, Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan
- Office of Radiation Technology, Keio University Hospital, Tokyo, Japan
| | - Christina Andica
- Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan
| | - Saori Koshino
- Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan
- Department of Radiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Tomoko Maekawa
- Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan
- Department of Radiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Ryusuke Irie
- Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan
- Department of Radiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Tomohiro Takamura
- Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan
| | | | - Osamu Abe
- Department of Radiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Shigeki Aoki
- Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan
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19
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Kenkel D, Yamada Y, Weiger M, Wurnig MC, Jungraithmayr W, Boss A. Magnetisation transfer as a biomarker for chronic airway fibrosis in a mouse lung transplantation model. Eur Radiol Exp 2018; 2:3. [PMID: 29708209 PMCID: PMC5909363 DOI: 10.1186/s41747-017-0032-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2017] [Accepted: 11/21/2017] [Indexed: 11/25/2022] Open
Abstract
Background Chronic airway fibrosis (CAF) is the most prevalent complication in human lung transplant recipients. The aim of the study is to evaluate magnetisation transfer (MT) as a biomarker of developing CAF of lung transplants in a mouse model. Methods Lung transplantation was performed in 48 mice, applying major or minor histocompatibility mismatches between strains for the induction of CAF. MT measurements were performed in vivo with systematic variation of off-resonance frequencies and flip angle of the MT prepulse. MT ratios (MTRs) were compared for lungs showing CAF and without CAF. Results Seven out of 24 animals (29%) showed a pattern of CAF at histology. All mice developing CAF also showed signs of acute rejection, whereas none of the lungs showed signs of other post-transplant complications. After lung transplantation, pulmonary infiltration was a frequent finding (14 out of 24) exhibiting a higher MTR (24.8% ± 4.5%) compared to well-ventilated lungs (12.3% ± 6.9%, p = 0.001) at 8000 Hz off-resonance frequency, 3000° flip angle. In infiltrated lung tissue exhibiting CAF, lower MTR values (21.8% ± 5.7%) were found compared to infiltrated lungs showing signs of acute rejection alone (26.5% ± 2.9%, p = 0.028), at 8000 Hz, 3000° flip angle. The highest MTR values were observed at 3000° flip angle, using a 1000 Hz off-resonance frequency. Conclusion MTR might serve as a tool for the detection of CAF in infiltrated lung tissue.
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Affiliation(s)
- David Kenkel
- 1Department of Diagnostic and Interventional Radiology, University Hospital Zurich, Ramistrasse 100, 8091 Zurich, Switzerland
| | - Yoshito Yamada
- 2Division of Thoracic Surgery and Department, University Hospital Zurich, Zurich, Switzerland
| | - Markus Weiger
- 3Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Moritz C Wurnig
- 1Department of Diagnostic and Interventional Radiology, University Hospital Zurich, Ramistrasse 100, 8091 Zurich, Switzerland
| | - Wolfgang Jungraithmayr
- 2Division of Thoracic Surgery and Department, University Hospital Zurich, Zurich, Switzerland.,Department of Thoracic Surgery, Medical University Brandenburg, Neuruppin, Brandenburg Germany
| | - Andreas Boss
- 1Department of Diagnostic and Interventional Radiology, University Hospital Zurich, Ramistrasse 100, 8091 Zurich, Switzerland
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20
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Van Obberghen E, Mchinda S, le Troter A, Prevost VH, Viout P, Guye M, Varma G, Alsop DC, Ranjeva JP, Pelletier J, Girard O, Duhamel G. Evaluation of the Sensitivity of Inhomogeneous Magnetization Transfer (ihMT) MRI for Multiple Sclerosis. AJNR Am J Neuroradiol 2018; 39:634-641. [PMID: 29472299 DOI: 10.3174/ajnr.a5563] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 12/22/2017] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Inhomogeneous magnetization transfer is a new endogenous MR imaging contrast mechanism that has demonstrated high specificity for myelin. Here, we tested the hypothesis that inhomogeneous magnetization transfer is sensitive to pathology in a population of patients with relapsing-remitting MS in a way that both differs from and complements conventional magnetization transfer. MATERIALS AND METHODS Twenty-five patients with relapsing-remitting MS and 20 healthy volunteers were enrolled in a prospective MR imaging research study, whose protocol included anatomic imaging, standard magnetization transfer, and inhomogeneous magnetization transfer imaging. Magnetization transfer and inhomogeneous magnetization transfer ratios measured in normal-appearing brain tissue and in MS lesions of patients were compared with values measured in control subjects. The potential association of inhomogeneous magnetization transfer ratio variations with the clinical scores (Expanded Disability Status Scale) of patients was further evaluated. RESULTS The magnetization transfer ratio and inhomogeneous magnetization transfer ratio measured in the thalami and frontal, occipital, and temporal WM of patients with MS were lower compared with those of controls (P < .05). The mean inhomogeneous magnetization transfer ratio measured in lesions was lower than that in normal-appearing WM (P < .05). Significant (P < .05) negative correlations were found between the clinical scores and inhomogeneous magnetization transfer ratio measured in normal-appearing WM structures. Weaker nonsignificant correlation trends were found for the magnetization transfer ratio. CONCLUSIONS The sensitivity of the inhomogeneous magnetization transfer technique for MS was highlighted by the reduction in the inhomogeneous magnetization transfer ratio in MS lesions and in normal-appearing WM of patients compared with controls. Stronger correlations with the Expanded Disability Status Scale score were obtained with the inhomogeneous magnetization transfer ratio compared with the standard magnetization transfer ratio, which may be explained by the higher specificity of inhomogeneous magnetization transfer for myelin.
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Affiliation(s)
- E Van Obberghen
- From Aix-Marseille Université (E.V.O., S.M., A.l.T., V.H.P., P.V., M.G., J.-P.R., J.P., O.G., G.D.), Centre de Résonance Magnétique Biologique et Médicale (CRMBM), UMR 7339 Centre National de Recherche Scientifique (CNRS), Marseille, France
| | - S Mchinda
- From Aix-Marseille Université (E.V.O., S.M., A.l.T., V.H.P., P.V., M.G., J.-P.R., J.P., O.G., G.D.), Centre de Résonance Magnétique Biologique et Médicale (CRMBM), UMR 7339 Centre National de Recherche Scientifique (CNRS), Marseille, France
| | - A le Troter
- From Aix-Marseille Université (E.V.O., S.M., A.l.T., V.H.P., P.V., M.G., J.-P.R., J.P., O.G., G.D.), Centre de Résonance Magnétique Biologique et Médicale (CRMBM), UMR 7339 Centre National de Recherche Scientifique (CNRS), Marseille, France
| | - V H Prevost
- From Aix-Marseille Université (E.V.O., S.M., A.l.T., V.H.P., P.V., M.G., J.-P.R., J.P., O.G., G.D.), Centre de Résonance Magnétique Biologique et Médicale (CRMBM), UMR 7339 Centre National de Recherche Scientifique (CNRS), Marseille, France
| | - P Viout
- From Aix-Marseille Université (E.V.O., S.M., A.l.T., V.H.P., P.V., M.G., J.-P.R., J.P., O.G., G.D.), Centre de Résonance Magnétique Biologique et Médicale (CRMBM), UMR 7339 Centre National de Recherche Scientifique (CNRS), Marseille, France
| | - M Guye
- From Aix-Marseille Université (E.V.O., S.M., A.l.T., V.H.P., P.V., M.G., J.-P.R., J.P., O.G., G.D.), Centre de Résonance Magnétique Biologique et Médicale (CRMBM), UMR 7339 Centre National de Recherche Scientifique (CNRS), Marseille, France
| | - G Varma
- Department of Radiology (G.V., D.C.A.), Division of MR Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - D C Alsop
- Department of Radiology (G.V., D.C.A.), Division of MR Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - J-P Ranjeva
- From Aix-Marseille Université (E.V.O., S.M., A.l.T., V.H.P., P.V., M.G., J.-P.R., J.P., O.G., G.D.), Centre de Résonance Magnétique Biologique et Médicale (CRMBM), UMR 7339 Centre National de Recherche Scientifique (CNRS), Marseille, France
| | - J Pelletier
- From Aix-Marseille Université (E.V.O., S.M., A.l.T., V.H.P., P.V., M.G., J.-P.R., J.P., O.G., G.D.), Centre de Résonance Magnétique Biologique et Médicale (CRMBM), UMR 7339 Centre National de Recherche Scientifique (CNRS), Marseille, France
- Aix-Marseille University (J.P.), Assistance Publique des Hôpitaux de Marseille (APHM), Hôpital de La Timone, Pôle de Neurosciences Cliniques, Service de Neurologie, Marseille, France
| | - O Girard
- From Aix-Marseille Université (E.V.O., S.M., A.l.T., V.H.P., P.V., M.G., J.-P.R., J.P., O.G., G.D.), Centre de Résonance Magnétique Biologique et Médicale (CRMBM), UMR 7339 Centre National de Recherche Scientifique (CNRS), Marseille, France
| | - G Duhamel
- From Aix-Marseille Université (E.V.O., S.M., A.l.T., V.H.P., P.V., M.G., J.-P.R., J.P., O.G., G.D.), Centre de Résonance Magnétique Biologique et Médicale (CRMBM), UMR 7339 Centre National de Recherche Scientifique (CNRS), Marseille, France
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21
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Gonzalez Caldito N, Antony B, He Y, Lang A, Nguyen J, Rothman A, Ogbuokiri E, Avornu A, Balcer L, Frohman E, Frohman TC, Bhargava P, Prince J, Calabresi PA, Saidha S. Analysis of Agreement of Retinal-Layer Thickness Measures Derived from the Segmentation of Horizontal and Vertical Spectralis OCT Macular Scans. Curr Eye Res 2017; 43:415-423. [PMID: 29240464 DOI: 10.1080/02713683.2017.1406526] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
PURPOSE Optical coherence tomography (OCT) is a reliable method used to quantify discrete layers of the retina. Spectralis OCT is a device used for this purpose. Spectralis OCT macular scan imaging acquisition can be obtained on either the horizontal or vertical plane. The vertical protocol has been proposed as favorable, due to postulated reduction in confound of Henle's fibers on segmentation-derived metrics. Yet, agreement of the segmentation measures of horizontal and vertical macular scans remains unexplored. Our aim was to determine this agreement. MATERIALS AND METHODS Horizontal and vertical macular scans on Spectralis OCT were acquired in 20 healthy controls (HCs) and 20 multiple sclerosis (MS) patients. All scans were segmented using Heidelberg software and a Johns Hopkins University (JHU)-developed method. Agreement was analyzed using Bland-Altman analyses and intra-class correlation coefficients (ICCs). RESULTS Using both segmentation techniques, mean differences (agreement at the cohort level) in the thicknesses of all macular layers derived from both acquisition protocols in MS patients and HCs were narrow (<1 µm), while the limits of agreement (LOA) (agreement at the individual level) were wider. Using JHU segmentation mean differences (and LOA) for the macular retinal nerve fiber layer (RNFL) and ganglion cell layer + inner plexiform layer (GCIP) in MS were 0.21 µm (-1.57-1.99 µm) and -0.36 µm (-1.44-1.37 µm), respectively. CONCLUSIONS OCT segmentation measures of discrete retinal-layer thicknesses derived from both vertical and horizontal protocols on Spectralis OCT agree excellently at the cohort level (narrow mean differences), but only moderately at the individual level (wide LOA). This suggests patients scanned using either protocol should continue to be scanned with the same protocol. However, due to excellent agreement at the cohort level, measures derived from both acquisitions can be pooled for outcome purposes in clinical trials.
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Affiliation(s)
| | - Bhavna Antony
- b Department of Electrical and Computer Engineering , Johns Hopkins University , Baltimore , MD , USA
| | - Yufan He
- b Department of Electrical and Computer Engineering , Johns Hopkins University , Baltimore , MD , USA
| | - Andrew Lang
- b Department of Electrical and Computer Engineering , Johns Hopkins University , Baltimore , MD , USA
| | - James Nguyen
- a Department of Neurology , Johns Hopkins University School of Medicine , Baltimore , MD , USA
| | - Alissa Rothman
- a Department of Neurology , Johns Hopkins University School of Medicine , Baltimore , MD , USA
| | - Esther Ogbuokiri
- a Department of Neurology , Johns Hopkins University School of Medicine , Baltimore , MD , USA
| | - Ama Avornu
- a Department of Neurology , Johns Hopkins University School of Medicine , Baltimore , MD , USA
| | - Laura Balcer
- c Department of Neurology , New York University Langone Medical Center , New York , NY , USA
| | - Elliot Frohman
- d Department of Neurology and Ophthalmology , University of Texas Austin Dell Medical School , Austin TX , USA
| | - Teresa C Frohman
- d Department of Neurology and Ophthalmology , University of Texas Austin Dell Medical School , Austin TX , USA
| | - Pavan Bhargava
- a Department of Neurology , Johns Hopkins University School of Medicine , Baltimore , MD , USA
| | - Jerry Prince
- b Department of Electrical and Computer Engineering , Johns Hopkins University , Baltimore , MD , USA
| | - Peter A Calabresi
- a Department of Neurology , Johns Hopkins University School of Medicine , Baltimore , MD , USA
| | - Shiv Saidha
- a Department of Neurology , Johns Hopkins University School of Medicine , Baltimore , MD , USA
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22
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Sled JG. Modelling and interpretation of magnetization transfer imaging in the brain. Neuroimage 2017; 182:128-135. [PMID: 29208570 DOI: 10.1016/j.neuroimage.2017.11.065] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 11/19/2017] [Accepted: 11/29/2017] [Indexed: 01/09/2023] Open
Abstract
Magnetization transfer contrast has yielded insight into brain tissue microstructure changes across the lifespan and in a range of disorders. This progress has been aided by the development of quantitative magnetization transfer imaging techniques able to extract intrinsic properties of the tissue that are independent of the specifics of the data acquisition. While the tissue properties extracted by these techniques do not map directly onto specific cellular structures or pathological processes, a growing body of work from animal models and histopathological correlations aids the in vivo interpretation of magnetization transfer properties of tissue. This review examines the biophysical models that have been developed to describe magnetization transfer contrast in tissue as well as the experimental evidence for the biological interpretation of magnetization transfer data in health and disease.
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Affiliation(s)
- John G Sled
- Hospital for Sick Children, Mouse Imaging Centre, Toronto, Ontario, Canada; Medical Biophysics, University of Toronto, Toronto, Ontario, Canada.
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23
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Thaler C, Faizy TD, Sedlacik J, Bester M, Stellmann JP, Heesen C, Fiehler J, Siemonsen S. The use of multiparametric quantitative magnetic resonance imaging for evaluating visually assigned lesion groups in patients with multiple sclerosis. J Neurol 2017; 265:127-133. [PMID: 29159467 DOI: 10.1007/s00415-017-8683-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 11/13/2017] [Accepted: 11/14/2017] [Indexed: 12/19/2022]
Abstract
In multiple sclerosis (MS), inflammatory lesions present a broad spectrum of histopathologic processes. For a better discrimination, lesions are visually defined into different lesion groups according to their appearance on conventional magnetic resonance imaging (MRI). The aim of this study was to investigate the properties of different MS lesion groups using multiparametric quantitative MRI. 35 patients diagnosed with relapsing-remitting MS received 3 Tesla MRI including magnetization-prepared 2 rapid acquisition gradient echo, diffusion tensor imaging and magnetization transfer imaging. Lesion segmentation was performed for T2 lesions, black holes and contrast-enhancing lesions. A subtraction mask was created including only T2 lesions that did not correspond to a black hole or contrast-enhancing lesion. T1 relaxation time (T1-RT), magnetization transfer ratio (MTR), mean diffusivity (MD) and fractional anisotropy (FA) were determined for every lesion and in normal-appearing white matter. Only MD differed significantly between all lesion groups and NAWM (p < 0.05), while FA differed between all lesion groups but not NAWM. T1-RT and MTR were not useful imaging biomarkers to distinguish between lesion groups. A lack of sensitivity and specificity and unproportional alterations of quantitative MRI measures, due to heterogenous histopathologic processes within lesions, may be a possible explanation for missing discrimination. Thus, not only interpretation of visually defined MS lesion but also interpretation of quantitative MRI measures remains challenging and should be conducted carefully.
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Affiliation(s)
- Christian Thaler
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany.
| | - Tobias D Faizy
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Jan Sedlacik
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Maxim Bester
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Jan-Patrick Stellmann
- Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Institute for Neuroimmunology and Clinical MS Research, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christoph Heesen
- Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Institute for Neuroimmunology and Clinical MS Research, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jens Fiehler
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Susanne Siemonsen
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
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24
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Zheng Y, Lee JC, Rudick R, Fisher E. Long-Term Magnetization Transfer Ratio Evolution in Multiple Sclerosis White Matter Lesions. J Neuroimaging 2017; 28:191-198. [PMID: 29076591 DOI: 10.1111/jon.12480] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 09/26/2017] [Accepted: 09/28/2017] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Magnetization transfer ratio (MTR), a magnetic resonance imaging technique used to assess tissue integrity, correlates with demyelination and axonal loss in multiple sclerosis (MS) lesions. In acute white matter lesions, short-term MTR changes mainly reflect demyelination and remyelination, in addition to edema and axonal and glial changes. Long-term MTR changes in MS lesions have not been studied extensively. METHODS A new quantitative image analysis method was developed to measure long-term MTR changes in MS lesions. The method was applied to a group of 59 patients and 14 healthy control subjects followed for 4 years. MTR changes in white matter lesions were analyzed, where lesion voxels were classified into six categories based on starting MTR and change over time. For each patient, the proportion of lesion voxels in each MTR-change category was calculated. Correlations between long-term MTR evolution, disability progression, and brain atrophy were investigated. RESULTS The proportion of lesion voxels in the high stable category correlated with less atrophy progression, while the proportion with low and increasing MTR correlated with increased atrophy. The proportion of lesion voxels in the high and stable MTR lesion category was significantly different between MS disease subgroups. The group with disability progression had a higher proportion of lesion voxels with low and increasing MTR. CONCLUSIONS These results suggest that long-term changes in MTR in white matter lesions can be used to distinguish lesion subtypes associated with MS disease progression and improve understanding of the temporal evolution of MS pathology.
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Affiliation(s)
- Yufan Zheng
- Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, OH.,Chemical and Biomedical Engineering, Cleveland State University, Cleveland, OH
| | - Jar-Chi Lee
- Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH
| | - Richard Rudick
- Mellen Center for Multiple Sclerosis Treatment and Research, Cleveland Clinic, Cleveland, OH
| | - Elizabeth Fisher
- Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, OH
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25
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Vavasour IM, Huijskens SC, Li DKB, Traboulsee AL, Mädler B, Kolind SH, Rauscher A, Moore GRW, MacKay AL, Laule C. Global loss of myelin water over 5 years in multiple sclerosis normal-appearing white matter. Mult Scler 2017; 24:1557-1568. [DOI: 10.1177/1352458517723717] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background: Reduced myelin water fraction (MWF, a marker for myelin), increased geometric mean T2 (ieGMT2, reflecting intra/extracellular water properties), and increased T1 (related to total water content) have been observed in cross-sectional studies of multiple sclerosis (MS) normal-appearing white matter (NAWM). Objective: To assess longitudinal changes of magnetic resonance (MR) measures in relapsing-remitting MS (RRMS) brain NAWM. Methods: A total of 11 subjects with RRMS and 4 controls were scanned on a 3T MRI at baseline and long-term follow-up (LTFU; 3.2–5.8 years) with a 32-echo T2 relaxation and an inversion recovery T1 sequence. For every voxel, MWF, ieGMT2, and T1 were obtained. Mean, peak height, and peak location from NAWM mask-based histograms were determined. Results: In MS subjects, NAWM MWF mean decreased by 8% ( p = 0.0016). No longitudinal changes were measured in T1 or ieGMT2. There was no relationship between change in any MR metric and change in EDSS. Control white matter showed no differences over time in any metric. Conclusion: The decreases we observed in MWF suggest that changes in myelin integrity and loss of myelin may be occurring diffusely and over long time periods in the MS brain. The timescale of these changes indicates that chronic, progressive myelin damage is an evolving process occurring over many years.
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Affiliation(s)
- Irene M Vavasour
- Department of Radiology, The University of British Columbia, Vancouver, BC, Canada
| | - Sophie C Huijskens
- Department of Physics and Astronomy, The University of British Columbia, Vancouver, BC, Canada
| | - David KB Li
- Department of Radiology, The University of British Columbia, Vancouver, BC, Canada; Department of Medicine, The University of British Columbia, Vancouver, BC, Canada
| | - Anthony L Traboulsee
- Department of Medicine, The University of British Columbia, Vancouver, BC, Canada
| | | | - Shannon H Kolind
- Department of Radiology, The University of British Columbia, Vancouver, BC, Canada; Department of Medicine, The University of British Columbia, Vancouver, BC, Canada
| | - Alexander Rauscher
- Paediatrics, Centre for Brain Health, Child and Family Research Institute, The University of British Columbia, Vancouver, BC, Canada
| | - GR Wayne Moore
- Department of Medicine, The University of British Columbia, Vancouver, BC, Canada/Department of Pathology and Laboratory Medicine, The University of British Columbia, Vancouver, BC, Canada/International Collaboration on Repair Discoveries (ICORD), The University of British Columbia, Vancouver, BC, Canada
| | - Alex L MacKay
- Department of Radiology, The University of British Columbia, Vancouver, BC, Canada; Department of Physics and Astronomy, The University of British Columbia, Vancouver, BC, Canada
| | - Cornelia Laule
- Department of Radiology, The University of British Columbia, Vancouver, BC, Canada/Department of Pathology and Laboratory Medicine, The University of British Columbia, Vancouver, BC, Canada/International Collaboration on Repair Discoveries (ICORD), The University of British Columbia, Vancouver, BC, Canada
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A Comparison of Neuroimaging Abnormalities in Multiple Sclerosis, Major Depression and Chronic Fatigue Syndrome (Myalgic Encephalomyelitis): is There a Common Cause? Mol Neurobiol 2017; 55:3592-3609. [PMID: 28516431 PMCID: PMC5842501 DOI: 10.1007/s12035-017-0598-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 05/03/2017] [Indexed: 01/23/2023]
Abstract
There is copious evidence of abnormalities in resting-state functional network connectivity states, grey and white matter pathology and impaired cerebral perfusion in patients afforded a diagnosis of multiple sclerosis, major depression or chronic fatigue syndrome (CFS) (myalgic encephalomyelitis). Systemic inflammation may well be a major element explaining such findings. Inter-patient and inter-illness variations in neuroimaging findings may arise at least in part from regional genetic, epigenetic and environmental variations in the functions of microglia and astrocytes. Regional differences in neuronal resistance to oxidative and inflammatory insults and in the performance of antioxidant defences in the central nervous system may also play a role. Importantly, replicated experimental findings suggest that the use of high-resolution SPECT imaging may have the capacity to differentiate patients afforded a diagnosis of CFS from those with a diagnosis of depression. Further research involving this form of neuroimaging appears warranted in an attempt to overcome the problem of aetiologically heterogeneous cohorts which probably explain conflicting findings produced by investigative teams active in this field. However, the ionising radiation and relative lack of sensitivity involved probably preclude its use as a routine diagnostic tool.
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Miller LG, Young JA, Ray SK, Wang G, Purohit S, Banik NL, Dasgupta S. Sphingosine Toxicity in EAE and MS: Evidence for Ceramide Generation via Serine-Palmitoyltransferase Activation. Neurochem Res 2017; 42:2755-2768. [PMID: 28474276 DOI: 10.1007/s11064-017-2280-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 04/07/2017] [Accepted: 04/22/2017] [Indexed: 12/12/2022]
Abstract
Multiple sclerosis (MS) is a demyelinating disorder characterized by massive neurodegeneration and profound axonal loss. Since myelin is enriched with sphingolipids and some of them display toxicity, biological function of sphingolipids in demyelination has been investigated in MS brain tissues. An elevation of sphingosine with a decrease in monoglycosylceramide and psychosine (myelin markers) was observed in MS white matter and plaque compared to normal brain tissue. This indicated that sphingosine toxicity might mediate oligodendrocyte degeneration. To explain the source of sphingosine accumulation, total sphingolipid profile was investigated in Lewis rats after inducing experimental autoimmune encephalomyelitis (EAE) and also in human oligodendrocytes in culture. An intermittent increase in ceramide followed by sphingosine accumulation in EAE spinal cord along with a stimulation of serine-palmitoyltransferase (SPT) activity was observed. Apoptosis was identified in the lumbar spinal cord, the most prominent demyelinating area, in the EAE rats. TNFα and IFNγ stimulation of oligodendrocytes in culture also led to an accumulation of ceramide with an elevation of sphingosine. Ceramide elevation was drastically blocked by myriocin, an inhibitor of SPT, and also by FTY720. Myriocin treatment also protected oligodendrocytes from cytokine mediated apoptosis or programmed cell death. Hence, we propose that sphingosine toxicity may contribute to demyelination in both EAE and MS, and the intermittent ceramide accumulation in EAE may, at least partly, be mediated via SPT activation, which is a novel observation that has not been previously reported.
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Affiliation(s)
- Lawrence G Miller
- Department of Neurology and Neurosurgery, Medical University of South Carolina, 96 Jonathan Lucas Street, Charleston, SC, 29425, USA
| | - Jennifer A Young
- Department of Neurology and Neurosurgery, Medical University of South Carolina, 96 Jonathan Lucas Street, Charleston, SC, 29425, USA
| | - Swapan K Ray
- Department of Pathology, Microbiology, and Immunology, University of South Carolina School of Medicine, 6439 Garners Ferry Road, Columbia, SC, 29209, USA
| | - Guanghu Wang
- Institute of Molecular Medicine and Genetics, Augusta University, 1120 15th Street, Augusta, GA, 30912, USA
| | - Sharad Purohit
- Center for Biotechnology and Genomic Medicine, Augusta University, 1120 15th Street, Augusta, GA, 30912, USA
| | - Naren L Banik
- Department of Neurology and Neurosurgery, Medical University of South Carolina, 96 Jonathan Lucas Street, Charleston, SC, 29425, USA
| | - Somsankar Dasgupta
- Institute of Molecular Medicine and Genetics, Augusta University, 1120 15th Street, Augusta, GA, 30912, USA.
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Davies GR, Hadjiprocopis A, Altmann DR, Chard DT, Griffin CM, Rashid W, Parker GJ, Tofts PS, Kapoor R, Thompson AJ, Miller DH. Normal-appearing grey and white matter T1 abnormality in early relapsing–remitting multiple sclerosis: a longitudinal study. Mult Scler 2017; 13:169-77. [PMID: 17439881 DOI: 10.1177/1352458506070726] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Objective To investigate the presence and evolution of T1 relaxation time abnormalities in normal-appearing white matter (NAWM) and grey matter (GM), early in the course of relapsing–remitting multiple sclerosis (MS). Methods Twenty-three patients with early relapsing–remitting MS and 14 healthy controls were imaged six monthly for up to three years. Mean follow-up was 26 months for MS patients and 24 months for controls. Dual-echo fast-spin echo and gradient-echo proton-density and T1-weighted data sets (permitting the calculation of a T1 map) were acquired in all subjects. GM and NAWM T1 histograms were produced and a hierarchical regression model was used to investigate changes in T1 over time. Results At baseline, significant patient-control differences were seen, both in NAWM (P = 0.001) and in GM (P = 0.01). At follow-up, there was no evidence for a serial change in either mean T1 or peak-location for either NAWM or GM. There was weak evidence for a decline in patient NAWM peak-height and also evidence for a decline in control GM peak-height. Conclusion There are significant and persistent abnormalities of NAWM and GM T1 in early relapsing-remitting MS. Further studies should address whether such T1 measures have a role in prognosis or therapeutic monitoring. Multiple Sclerosis 2007; 13:169–177. http://msj.sagepub.com
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Affiliation(s)
- G R Davies
- NMR Research Unit, Institute of Neurology, University College London, Queen Square, London, UK
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Kipp M, Nyamoya S, Hochstrasser T, Amor S. Multiple sclerosis animal models: a clinical and histopathological perspective. Brain Pathol 2017; 27:123-137. [PMID: 27792289 DOI: 10.1111/bpa.12454] [Citation(s) in RCA: 158] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Accepted: 10/26/2016] [Indexed: 12/11/2022] Open
Abstract
There is a broad consensus that multiple sclerosis (MS) represents more than an inflammatory disease: it harbors several characteristic aspects of a classical neurodegenerative disorder, that is, damage to axons, synapses and nerve cell bodies. While we are equipped with appropriate therapeutic options to prevent immune-cell driven relapses, effective therapeutic options to prevent the progressing neurodegeneration are still missing. In this review article, we will discuss to what extent pathology of the progressive disease stage can be modeled in MS animal models. While acute and relapsing-remitting forms of experimental autoimmune encephalomyelitis (EAE), which are T cell dependent, are aptly suited to model relapsing-remitting phases of MS, other EAE models, especially the secondary progressive EAE stage in Biozzi ABH mice is better representing the secondary progressive phase of MS, which is refractory to many immune therapies. Besides EAE, the cuprizone model is rapidly gaining popularity to study the formation and progression of demyelinating CNS lesions without T cell involvement. Here, we discuss these two non-popular MS models. It is our aim to point out the pathological hallmarks of MS, and discuss which pathological aspects of the disease can be best studied in the various animal models available.
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Affiliation(s)
- Markus Kipp
- Department of Neuroanatomy, Faculty of Medicine, LMU München University, München, 80336, Germany
| | - Stella Nyamoya
- Department of Neuroanatomy, Faculty of Medicine, LMU München University, München, 80336, Germany.,Institute of Neuroanatomy, Faculty of Medicine, RWTH Aachen University, Aachen, D-52074, Germany
| | - Tanja Hochstrasser
- Department of Neuroanatomy, Faculty of Medicine, LMU München University, München, 80336, Germany
| | - Sandra Amor
- Department of Pathology, VU University Medical Centre, Amsterdam, The Netherlands.,Barts and The London School of Medicine and Dentistry, Neuroimmunology Unit, , Queen Mary University of London, Neuroscience Centre, Blizard Institute of Cell and Molecular Science, London, UK
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Lema A, Bishop C, Malik O, Mattoscio M, Ali R, Nicholas R, Muraro PA, Matthews PM, Waldman AD, Newbould RD. A Comparison of Magnetization Transfer Methods to Assess Brain and Cervical Cord Microstructure in Multiple Sclerosis. J Neuroimaging 2016; 27:221-226. [PMID: 27491693 DOI: 10.1111/jon.12377] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 06/25/2016] [Accepted: 06/26/2016] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Demyelination is a core pathological feature of multiple sclerosis (MS) and spontaneous remyelination appears to be an important mechanism for repair in the disease. Magnetization transfer ratio imaging (MTR) has been used extensively to evaluate demyelination, although limitations to its specificity are recognized. MT saturation imaging (MTsat) removes some of the T1 dependence of MTR. We have performed a comparative evaluation of MTR and MTsat imaging in a mixed group of subjects with active MS, to explore their relative sensitivity to pathology relevant to explaining clinical outcomes. METHODS A total of 134 subjects underwent MRI of their brain and cervical spinal cord. Isotropic 3-dimensional pre- and postcontrast T1-weighted and T2-weighted fluid-attenuated inversion recovery (FLAIR) volumes were segmented into brain normal appearing white matter (NAWM), brain WM lesions (WML), normal appearing spinal cord (NASC), and spinal cord lesions. Volumes and metrics for MTR and MTsat histograms were calculated for each region. RESULTS Significant Spearman correlations were found with the Expanded Disability Status Scale and timed 25-foot walk for the whole brain and WML MTR, but not in that from the NAWM or any cervical spinal cord region. By contrast, the MTsat was correlated with both disability metrics in all these regions in both the brain and spine. CONCLUSIONS This study extends prior work relating atrophy and lesion load with disability, by characterization of MTsat parameters. MTsat is practical in routine clinical applications and may be more sensitive to tissue damage than MTR for both brain and cervical spinal cord.
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Affiliation(s)
- Alfonso Lema
- Division of Brain Sciences, Department of Medicine, Imperial College London, London, UK
| | | | - Omar Malik
- Division of Brain Sciences, Department of Medicine, Imperial College London, London, UK
| | - Miriam Mattoscio
- Division of Brain Sciences, Department of Medicine, Imperial College London, London, UK
| | - Rehiana Ali
- Division of Brain Sciences, Department of Medicine, Imperial College London, London, UK
| | - Richard Nicholas
- Division of Brain Sciences, Department of Medicine, Imperial College London, London, UK
| | - Paolo A Muraro
- Division of Brain Sciences, Department of Medicine, Imperial College London, London, UK
| | - Paul M Matthews
- Division of Brain Sciences, Department of Medicine, Imperial College London, London, UK
| | - Adam D Waldman
- Department of Imaging, Imperial College Healthcare NHS Trust, London, UK
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Cassol E, Ranjeva JP, Ibarrola D, Mékies C, Manelfe C, Clanet M, Berry I. Diffusion tensor imaging in multiple sclerosis: a tool for monitoring changes in normal-appearing white matter. Mult Scler 2016; 10:188-96. [PMID: 15124766 DOI: 10.1191/1352458504ms997oa] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Our objectives were to determine the reproducibility of diffusion tensor imaging (DTI) in volunteers and to evaluate the ability of the method to monitor longitudinal changes occurring in the normal-appearing white matter (NAWM) of patients with multiple sclerosis (MS). DTI was performed three-mo nthly for one year in seven MS patients: three relapsing-remitting (RRMS), three secondary progressive (SPMS) and one relapsing SP. They were selected with a limited cerebral lesion load. Seven age- and sex-matched controls also underwent monthly examinations for three months. Diffusivity and anisotropy were quantified over the segmented whole supratentorial white matter, with the indices of trace (Tr) and fractional anisotropy (FA). Results obtained in volunteers show the reproducibility of the method. Patients had higher trace and lower anisotropy than matched controls (P B-0.0001). O ver the follow-up, both Tr and FA indicated a recovery after the acute phase in RRMS and a progressive shift towards abnormal values in SPMS. A lthough this result is not statistically significant, it suggests that DTI is sensitive to microscopic changes occurring in tissue of normal appearance in conventional images and could be useful for monitoring the course of the disease, even though it was unable to clearly distinguish between the various physiopathological processes involved.
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Affiliation(s)
- Emmanuelle Cassol
- Department of Biophysics and Multimodality Imaging, University Paul Sabatier, Toulouse-Rangueil, France
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Castriota-Scanderbeg A, Fasano F, Filippi M, Caltagirone C. T1 relaxation maps allow differentiation between pathologic tissue subsets in relapsing-remitting and secondary progressive multiple sclerosis. Mult Scler 2016; 10:556-61. [PMID: 15471373 DOI: 10.1191/1352458504ms1073oa] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In an attempt to clarify whether T1 relaxation time mapping may assist in characterizing the pathological brain tissue substrate of multiple sclerosis (MS), we compared the T1 relaxation times of lesions, areas of normal-appearing white matter (NAWM) located proximal to lesions, and areas of NAWM located distant from lesions in 12 patients with the relapsing-remitting and 12 with the secondary progressive (SP) subtype of disease. Nine healthy volunteers served as controls. Calculated mean T1 values were averaged across all patients within each clinical group, and comparisons were made by means of the Mann-Whitney U-test. Significant differences were found between all investigated brain regions within each clinical subgroup. Significant differences were also detected for each investigated brain region among clinical subgroups. While T1 values of NAWM were significantly higher in patients with SP disease than in normal white matter (NWM) of controls, no differences were detected when corresponding brain areas of patients with RR MS were compared with NWM of controls. T1 maps identify areas of the brain that are damaged to a different extent in patients with MS, and may be of help in monitoring disease progression.
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Swanson SD, Malyarenko DI, Fabiilli ML, Welsh RC, Nielsen JF, Srinivasan A. Molecular, dynamic, and structural origin of inhomogeneous magnetization transfer in lipid membranes. Magn Reson Med 2016; 77:1318-1328. [PMID: 27029318 DOI: 10.1002/mrm.26210] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 02/06/2016] [Accepted: 02/18/2016] [Indexed: 02/04/2023]
Abstract
PURPOSE To elucidate the dynamic, structural, and molecular properties that create inhomogeneous magnetization transfer (ihMT) contrast. METHODS Amphiphilic lipids, lamellar phospholipids with cholesterol, and bovine spinal cord (BSC) specimens were examined along with nonlipid systems. Magnetization transfer (MT), enhanced MT (eMT, obtained with double-sided radiofrequency saturation), ihMT (MT - eMT), and dipolar relaxation, T1D , were measured at 2.0 and 11.7 T. RESULTS The amplitude of ihMT ratio (ihMTR) is positively correlated with T1D values. Both ihMTR and T1D increase with increasing temperature in BSC white matter and in phospholipids and decrease with temperature in other lipids. Changes in ihMTR with temperature arise primarily from alterations in MT rather than eMT. Spectral width of MT, eMT, and ihMT increases with increasing carbon chain length. CONCLUSIONS Concerted motions of phospholipids in white matter decrease proton spin diffusion leading to increased proton T1D times and increased ihMT amplitudes, consistent with decoupling of Zeeman and dipolar spin reservoirs. Molecular specificity and dynamic sensitivity of ihMT contrast make it a suitable candidate for probing myelin membrane disorders. Magn Reson Med 77:1318-1328, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Scott D Swanson
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | | | - Mario L Fabiilli
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Robert C Welsh
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Jon-Fredrik Nielsen
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Ashok Srinivasan
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
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Harlow DE, Honce JM, Miravalle AA. Remyelination Therapy in Multiple Sclerosis. Front Neurol 2015; 6:257. [PMID: 26696956 PMCID: PMC4674562 DOI: 10.3389/fneur.2015.00257] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 11/23/2015] [Indexed: 01/10/2023] Open
Abstract
Multiple sclerosis (MS) is an immune-mediated disorder of the central nervous system that results in destruction of the myelin sheath that surrounds axons and eventual neurodegeneration. Current treatments approved for the treatment of relapsing forms of MS target the aberrant immune response and successfully reduce the severity of attacks and frequency of relapses. Therapies are still needed that can repair damage particularly for the treatment of progressive forms of MS for which current therapies are relatively ineffective. Remyelination can restore neuronal function and prevent further neuronal loss and clinical disability. Recent advancements in our understanding of the molecular and cellular mechanisms regulating myelination, as well as the development of high-throughput screens to identify agents that enhance myelination, have lead to the identification of many potential remyelination therapies currently in preclinical and early clinical development. One problem that has plagued the development of treatments to promote remyelination is the difficulty in assessing remyelination in patients with current imaging techniques. Powerful new imaging technologies are making it easier to discern remyelination in patients, which is critical for the assessment of these new therapeutic strategies during clinical trials. This review will summarize what is currently known about remyelination failure in MS, strategies to overcome this failure, new therapeutic treatments in the pipeline for promoting remyelination in MS patients, and new imaging technologies for measuring remyelination in patients.
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Affiliation(s)
- Danielle E Harlow
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus , Aurora, CO , USA
| | - Justin M Honce
- Department of Radiology, University of Colorado Anschutz Medical Campus , Aurora, CO , USA
| | - Augusto A Miravalle
- Department of Neurology, University of Colorado Anschutz Medical Campus , Aurora, CO , USA
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Al-Radaideh A, Mougin OE, Lim SY, Chou IJ, Constantinescu CS, Gowland P. Histogram analysis of quantitative T1 and MT maps from ultrahigh field MRI in clinically isolated syndrome and relapsing-remitting multiple sclerosis. NMR IN BIOMEDICINE 2015; 28:1374-1382. [PMID: 26346925 DOI: 10.1002/nbm.3385] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 07/19/2015] [Accepted: 07/27/2015] [Indexed: 06/05/2023]
Abstract
This study used quantitative MRI to study normal appearing white matter (NAWM) in patients with clinically isolated syndromes suggestive of multiple sclerosis and relapsing-remitting multiple sclerosis (RRMS). This was done at ultrahigh field (7 T) for greater spatial resolution and sensitivity. 17 CIS patients, 11 RRMS patients, and 20 age-matched healthy controls were recruited. They were scanned using a 3D inversion recovery turbo field echo sequence to measure the longitudinal relaxation time (T1). A 3D magnetization transfer prepared turbo field echo (MT-TFE) sequence was also acquired, first without a presaturation pulse and then with the MT presaturation pulse applied at -1.05 kHz and +1.05 kHz off resonance from water to produce two magnetization transfer ratio maps (MTR(-) and MTR(+)). Histogram analysis was performed on the signal from the voxels in the NAWM mask. The upper quartile cut-off of the T1 histogram was significantly higher in RRMS patients than in controls (p < 0.05), but there was no difference in CIS. In contrast, MTR was significantly different between CIS or RRMS patients and controls (p < 0.05) for most histogram measures considered. The difference between MTR(+) and MTR(-) signals showed that NOE contributions dominated the changes found. There was a weak negative correlation (r = -0.46, p < 0.05) between the mode of T1 distributions and healthy controls' age; this was not significant for MTR(+) (r = -0.34, p > 0.05) or MTR(-) (r = 0.13, p > 0.05). There was no significant correlation between the median of T1, MTR(-), or MTR(+) and the age of healthy controls. Furthermore, no significant correlation was observed between EDSS or disease duration and T1, MTR(-), or MTR(+) for either CIS or RRMS patients. In conclusion, MTR was found to be more sensitive to early changes in MS disease than T1.
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Affiliation(s)
- Ali Al-Radaideh
- Medical Imaging, The Hashemite University, Zarqa, Jordan
- Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, UK
| | - Olivier E Mougin
- Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, UK
| | - Su-Yin Lim
- Clinical Neuroscience, University of Nottingham, Nottingham, UK
| | - I-Jun Chou
- Clinical Neuroscience, University of Nottingham, Nottingham, UK
- Paediatric Neurology, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | | | - Penny Gowland
- Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, UK
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Watanabe T, Frahm J, Michaelis T. In Vivo Brain MR Imaging at Subnanoliter Resolution: Contrast and Histology. Magn Reson Med Sci 2015; 15:11-25. [PMID: 26346405 DOI: 10.2463/mrms.2015-0048] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
This article provides an overview of in vivo magnetic resonance (MR) imaging contrasts obtained for mammalian brain in relation to histological knowledge. Emphasis is paid to the (1) significance of high spatial resolution for the optimization of T1, T2, and magnetization transfer contrast, (2) use of exogenous extra- and intracellular contrast agents for validating endogenous contrast sources, and (3) histological structures and biochemical compounds underlying these contrasts and (4) their relevance to neuroradiology. Comparisons between MR imaging at subnanoliter resolution and histological data indicate that (a) myelin sheaths, (b) nerve cells, and (c) the neuropil are most responsible for observed MR imaging contrasts, while (a) diamagnetic macromolecules, (b) intracellular paramagnetic ions, and (c) extracellular free water, respectively, emerge as the dominant factors. Enhanced relaxation rates due to paramagnetic ions, such as iron and manganese, have been observed for oligodendrocytes, astrocytes, microglia, and blood cells in the brain as well as for nerve cells. Taken together, a plethora of observations suggests that the delineation of specific structures in high-resolution MR imaging of mammalian brain and the absence of corresponding contrasts in MR imaging of the human brain do not necessarily indicate differences between species but may be explained by partial volume effects. Second, paramagnetic ions are required in active cells in vivo which may reduce the magnetization transfer ratio in the brain through accelerated T1 recovery. Third, reductions of the magnetization transfer ratio may be more sensitive to a particular pathological condition, such as astrocytosis, microglial activation, inflammation, and demyelination, than changes in relaxation. This is because the simultaneous occurrence of increased paramagnetic ions (i.e., shorter relaxation times) and increased free water (i.e., longer relaxation times) may cancel T1 or T2 effects, whereas both processes reduce the magnetization transfer ratio.
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Affiliation(s)
- Takashi Watanabe
- Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut für biophysikalische Chemie
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Stikov N, Campbell JS, Stroh T, Lavelée M, Frey S, Novek J, Nuara S, Ho MK, Bedell BJ, Dougherty RF, Leppert IR, Boudreau M, Narayanan S, Duval T, Cohen-Adad J, Picard PA, Gasecka A, Côté D, Pike GB. In vivo histology of the myelin g-ratio with magnetic resonance imaging. Neuroimage 2015; 118:397-405. [DOI: 10.1016/j.neuroimage.2015.05.023] [Citation(s) in RCA: 207] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Revised: 05/08/2015] [Accepted: 05/08/2015] [Indexed: 11/25/2022] Open
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Lévy S, Benhamou M, Naaman C, Rainville P, Callot V, Cohen-Adad J. White matter atlas of the human spinal cord with estimation of partial volume effect. Neuroimage 2015; 119:262-71. [PMID: 26099457 DOI: 10.1016/j.neuroimage.2015.06.040] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2015] [Revised: 05/24/2015] [Accepted: 06/13/2015] [Indexed: 12/14/2022] Open
Abstract
Template-based analysis has proven to be an efficient, objective and reproducible way of extracting relevant information from multi-parametric MRI data. Using common atlases, it is possible to quantify MRI metrics within specific regions without the need for manual segmentation. This method is therefore free from user-bias and amenable to group studies. While template-based analysis is common procedure for the brain, there is currently no atlas of the white matter (WM) spinal pathways. The goals of this study were: (i) to create an atlas of the white matter tracts compatible with the MNI-Poly-AMU template and (ii) to propose methods to quantify metrics within the atlas that account for partial volume effect. The WM atlas was generated by: (i) digitalizing an existing WM atlas from a well-known source (Gray's Anatomy), (ii) registering this atlas to the MNI-Poly-AMU template at the corresponding slice (C4 vertebral level), (iii) propagating the atlas throughout all slices of the template (C1 to T6) using regularized diffeomorphic transformations and (iv) computing partial volume values for each voxel and each tract. Several approaches were implemented and validated to quantify metrics within the atlas, including weighted-average and Gaussian mixture models. Proof-of-concept application was done in five subjects for quantifying magnetization transfer ratio (MTR) in each tract of the atlas. The resulting WM atlas showed consistent topological organization and smooth transitions along the rostro-caudal axis. The median MTR across tracts was 26.2. Significant differences were detected across tracts, vertebral levels and subjects, but not across laterality (right-left). Among the different tested approaches to extract metrics, the maximum a posteriori showed highest performance with respect to noise, inter-tract variability, tract size and partial volume effect. This new WM atlas of the human spinal cord overcomes the biases associated with manual delineation and partial volume effect. Combined with multi-parametric data, the atlas can be applied to study demyelination and degeneration in diseases such as multiple sclerosis and will facilitate the conduction of longitudinal and multi-center studies.
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Affiliation(s)
- S Lévy
- Neuroimaging Research Laboratory (NeuroPoly), Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada; Functional Neuroimaging Unit, CRIUGM, Université de Montréal, Montreal, QC, Canada
| | - M Benhamou
- Neuroimaging Research Laboratory (NeuroPoly), Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada
| | - C Naaman
- Neuroimaging Research Laboratory (NeuroPoly), Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada
| | - P Rainville
- Functional Neuroimaging Unit, CRIUGM, Université de Montréal, Montreal, QC, Canada; Department of Stomatology, Université de Montréal, Montreal, QC, Canada
| | - V Callot
- Aix-Marseille Université (AMU), CNRS, CRMBM UMR 7339, 13385 Marseille, France; APHM, Hôpital de la Timone, CEMEREM, 13005 Marseille, France
| | - J Cohen-Adad
- Neuroimaging Research Laboratory (NeuroPoly), Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada; Functional Neuroimaging Unit, CRIUGM, Université de Montréal, Montreal, QC, Canada.
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Fjær S, Bø L, Myhr KM, Torkildsen Ø, Wergeland S. Magnetization transfer ratio does not correlate to myelin content in the brain in the MOG-EAE mouse model. Neurochem Int 2015; 83-84:28-40. [PMID: 25744931 DOI: 10.1016/j.neuint.2015.02.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2014] [Revised: 01/29/2015] [Accepted: 02/24/2015] [Indexed: 12/27/2022]
Abstract
Magnetization transfer ratio (MTR) is a magnetic resonance imaging (MRI) method which may detect demyelination not detected by conventional MRI in the central nervous system of patients with multiple sclerosis (MS). A decrease in MTR value has previously been shown to correlate to myelin loss in the mouse cuprizone model for demyelination. In this study, we investigated the sensitivity of MTR for demyelination in the myelin oligodendrocyte (MOG) 1-125 induced experimental autoimmune encephalomyelitis (EAE) mouse model. A total of 24 female c57Bl/6 mice were randomized to a control group (N = 6) or EAE (N = 18). MTR images were obtained at a preclinical 7 Tesla Bruker MR-scanner before EAE induction (baseline), 17-19 days (midpoint) and 31-32 days (endpoint) after EAE induction. Mean MTR values were calculated in five regions of the brain and compared to weight, EAE severity score and myelin content assessed by immunostaining for proteolipid protein and luxol fast blue, lymphocyte and monocyte infiltration and iron deposition. Contrary to what was expected, MTR values in the EAE mice were higher than in the control mice at the midpoint and endpoint. No significant difference in myelin content was found according to histo- or immunohistochemistry. Changes in MTR values did not correlate to myelin content, iron content, lymphocyte or monocyte infiltration, weight or EAE severity scores. This suggest that MTR measures of brain tissue can give significant differences between control mice and EAE mice not caused by demyelination, inflammation or iron deposition, and may not be useful surrogate markers for demyelination in the MOG1-125 mouse model.
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Affiliation(s)
- Sveinung Fjær
- KG Jebsen Centre for MS-Research, Department of Clinical Medicine, University of Bergen, Bergen, Norway; The Norwegian Multiple Sclerosis Competence Centre, Department of Neurology, Haukeland University Hospital, Bergen, Norway.
| | - Lars Bø
- KG Jebsen Centre for MS-Research, Department of Clinical Medicine, University of Bergen, Bergen, Norway; The Norwegian Multiple Sclerosis Competence Centre, Department of Neurology, Haukeland University Hospital, Bergen, Norway
| | - Kjell-Morten Myhr
- KG Jebsen Centre for MS-Research, Department of Clinical Medicine, University of Bergen, Bergen, Norway; The Norwegian Multiple Sclerosis Competence Centre, Department of Neurology, Haukeland University Hospital, Bergen, Norway
| | - Øivind Torkildsen
- KG Jebsen Centre for MS-Research, Department of Clinical Medicine, University of Bergen, Bergen, Norway; The Norwegian Multiple Sclerosis Competence Centre, Department of Neurology, Haukeland University Hospital, Bergen, Norway
| | - Stig Wergeland
- KG Jebsen Centre for MS-Research, Department of Clinical Medicine, University of Bergen, Bergen, Norway; The Norwegian Multiple Sclerosis Competence Centre, Department of Neurology, Haukeland University Hospital, Bergen, Norway
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Mallik S, Samson RS, Wheeler-Kingshott CAM, Miller DH. Imaging outcomes for trials of remyelination in multiple sclerosis. J Neurol Neurosurg Psychiatry 2014; 85:1396-404. [PMID: 24769473 PMCID: PMC4335693 DOI: 10.1136/jnnp-2014-307650] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 03/27/2014] [Accepted: 03/30/2014] [Indexed: 12/02/2022]
Abstract
Trials of potential neuroreparative agents are becoming more important in the spectrum of multiple sclerosis research. Appropriate imaging outcomes are required that are feasible from a time and practicality point of view, as well as being sensitive and specific to myelin, while also being reproducible and clinically meaningful. Conventional MRI sequences have limited specificity for myelination. We evaluate the imaging modalities which are potentially more specific to myelin content in vivo, such as magnetisation transfer ratio (MTR), restricted proton fraction f (from quantitative magnetisation transfer measurements), myelin water fraction and diffusion tensor imaging (DTI) metrics, in addition to positron emission tomography (PET) imaging. Although most imaging applications to date have focused on the brain, we also consider measures with the potential to detect remyelination in the spinal cord and in the optic nerve. At present, MTR and DTI measures probably offer the most realistic and feasible outcome measures for such trials, especially in the brain. However, no one measure currently demonstrates sufficiently high sensitivity or specificity to myelin, or correlation with clinical features, and it should be useful to employ more than one outcome to maximise understanding and interpretation of findings with these sequences. PET may be less feasible for current and near-future trials, but is a promising technique because of its specificity. In the optic nerve, visual evoked potentials can indicate demyelination and should be correlated with an imaging outcome (such as optic nerve MTR), as well as clinical measures.
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Affiliation(s)
- Shahrukh Mallik
- Department of Neuroinflammation, NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London (UCL) Institute of Neurology, London, UK
| | - Rebecca S Samson
- Department of Neuroinflammation, NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London (UCL) Institute of Neurology, London, UK
| | - Claudia A M Wheeler-Kingshott
- Department of Neuroinflammation, NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London (UCL) Institute of Neurology, London, UK
| | - David H Miller
- Department of Neuroinflammation, NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London (UCL) Institute of Neurology, London, UK
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Malyarenko DI, Zimmermann EM, Adler J, Swanson SD. Magnetization transfer in lamellar liquid crystals. Magn Reson Med 2014; 72:1427-34. [PMID: 24258798 PMCID: PMC4028438 DOI: 10.1002/mrm.25034] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 09/18/2013] [Accepted: 10/15/2013] [Indexed: 11/11/2022]
Abstract
PURPOSE This study examines the relationship between quantitative magnetization transfer (qMT) parameters and the molecular composition of a model lamellar liquid crystal (LLC) system composed of 1-decyl alcohol (decanol), sodium dodecyl sulfate (SDS), and water. METHODS Samples were made within a stable lamellar mesophase to provide different ratios of total semisolid protons (SDS + decanol) to water protons. Data were collected as a function of radiofrequency power, frequency offset, and temperature. qMT parameters were estimated by fitting a standard model to the data. Fitting results of four different semisolid line shapes were compared. RESULTS A super-Lorentzian line shape for the semisolid component provided the best fit. The estimated amount of semisolids was proportional to the ratio of decanol-to-water protons. Other qMT parameters exhibited nonlinear dependence on sample composition. Magnetization transfer ratio (MTR) was a linear function of the semisolid fraction over a limited range of decanol concentration. CONCLUSION In LLC samples, MT between semisolid and water originates from intramolecular nOe among decanol aliphatic chain protons followed by proton exchange between decanol hydroxyl and water. Exchange kinetics is influenced by SDS, although SDS protons do not participate in MT. These studies provide clinically relevant range of semisolid fraction proportional to detected MTR.
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Affiliation(s)
| | - Ellen M. Zimmermann
- Department of Internal Medicine - Gastroenterology, University of Michigan, Ann Arbor, MI, United States
| | - Jeremy Adler
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI, United States
| | - Scott D. Swanson
- Department of Radiology, University of Michigan, Ann Arbor, MI, United States
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Lerner A, Mogensen MA, Kim PE, Shiroishi MS, Hwang DH, Law M. Clinical Applications of Diffusion Tensor Imaging. World Neurosurg 2014; 82:96-109. [DOI: 10.1016/j.wneu.2013.07.083] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Revised: 07/04/2013] [Accepted: 07/26/2013] [Indexed: 10/26/2022]
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Evans MC, Serres S, Khrapitchev AA, Stolp HB, Anthony DC, Talbot K, Turner MR, Sibson NR. T₂-weighted MRI detects presymptomatic pathology in the SOD1 mouse model of ALS. J Cereb Blood Flow Metab 2014; 34:785-93. [PMID: 24496176 PMCID: PMC4013759 DOI: 10.1038/jcbfm.2014.19] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Revised: 12/10/2013] [Accepted: 12/24/2013] [Indexed: 12/13/2022]
Abstract
Neuroinflammation has been identified as a potential therapeutic target in amyotrophic lateral sclerosis (ALS), but relevant biomarkers are needed. The superoxide dismutase (SOD1)(G93A) transgenic mouse model of ALS offers a unique opportunity to study and potentially manipulate presymptomatic pathology. While T₂-weighted magnetic resonance imaging (MRI) has been shown to be sensitive to pathologic changes at symptom onset, no earlier biomarkers were previously identified and the underlying histopathologic correlates remain uncertain. To address these issues, we used a multimodal MRI approach targeting structural (T₂, T₁, apparent diffusion coefficient (ADC), magnetization transfer ratio (MTR)), vascular (gadolinium diethylene triamine pentaacetic acid), and endothelial (vascular cell adhesion molecule-microparticles of iron oxide) changes, together with histopathologic analysis from presymptomatic to symptomatic stages of disease. Presymptomatic changes in brainstem nuclei were evident on T₂-weighted images from as early as 60 days (P<0.05). Histologic indices of vacuolation, astro- and microglial activation all correlated with T₂-weighted changes. Significant reductions in ADC (P<0.01) and MTR (P<0.05) were found at 120 days in the same brainstem nuclei. No changes in T₁ relaxation, vascular permeability, or endothelial activation were found at any stage of disease. These findings suggest that T₂-weighted MRI offers the strongest biomarker potential in this model, and that MRI has unique potential for noninvasive and longitudinal assessment of presymptomatically applied therapeutic and neuroprotective agents.
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Affiliation(s)
- Matthew C Evans
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
- CR-UK/MRC Gray Institute for Radiation Oncology and Biology, Department of Oncology, University of Oxford, Oxford, UK
| | - Sébastien Serres
- CR-UK/MRC Gray Institute for Radiation Oncology and Biology, Department of Oncology, University of Oxford, Oxford, UK
| | - Alexandre A Khrapitchev
- CR-UK/MRC Gray Institute for Radiation Oncology and Biology, Department of Oncology, University of Oxford, Oxford, UK
| | - Helen B Stolp
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
- Department of Pharmacology, University of Oxford, Oxford, UK
| | | | - Kevin Talbot
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Martin R Turner
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Nicola R Sibson
- CR-UK/MRC Gray Institute for Radiation Oncology and Biology, Department of Oncology, University of Oxford, Oxford, UK
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Štecková T, Hluštík P, Sládková V, Odstrčil F, Mareš J, Kaňovský P. Thalamic atrophy and cognitive impairment in clinically isolated syndrome and multiple sclerosis. J Neurol Sci 2014; 342:62-8. [PMID: 24819917 DOI: 10.1016/j.jns.2014.04.026] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 04/15/2014] [Accepted: 04/21/2014] [Indexed: 11/19/2022]
Abstract
BACKGROUND Cognitive deficits worsen the quality of life in multiple sclerosis and may be predicted by deep gray matter atrophy, especially thalamic atrophy. This relationship has not been studied in the clinically isolated syndrome (CIS). The aims of this study were to assess cognitive deficits in patients with CIS and relapsing-remitting multiple sclerosis (RRMS) using neuropsychological testing, to search for thalamic atrophy on brain MRI, and to test for their correlations. METHODS Forty-three patients (19 with CIS and 24 with RRMS) underwent brain MRI and neuropsychological testing involving multiple cognitive domains and the severity of depression. Thalamic volumes automatically segmented from MRI data were compared to 19 healthy controls. Correlations were sought between cognitive performance and thalamic volume. RESULTS Cognitive impairment was detected in the majority of both CIS and MS patients, most affected in executive functions, auditory memory, lexical verbal fluency, distribution of attention and psychomotor speed. Cognitive impairment and depression were not significantly correlated to disease duration. Both CIS and MS patients demonstrated thalamic atrophy compared to controls, while many cognitive deficits correlated with thalamic volume in both patient groups. CONCLUSION Cognitive deficits in CIS resemble those found in the later stages of MS and may be directly related to the amount of thalamic damage.
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Affiliation(s)
- Tereza Štecková
- Department of Neurology, Faculty of Medicine and Dentistry, Palacky University and Faculty Hospital Olomouc, I. P. Pavlova 6, 77520 Olomouc, Czech Republic; Department of Clinical Psychology, Faculty of Medicine and Dentistry, Palacky University and Faculty Hospital Olomouc, Palacky University in Olomouc, I. P. Pavlova 6, 77520 Olomouc, Czech Republic.
| | - Petr Hluštík
- Department of Neurology, Faculty of Medicine and Dentistry, Palacky University and Faculty Hospital Olomouc, I. P. Pavlova 6, 77520 Olomouc, Czech Republic
| | - Vladimíra Sládková
- Department of Neurology, Faculty of Medicine and Dentistry, Palacky University and Faculty Hospital Olomouc, I. P. Pavlova 6, 77520 Olomouc, Czech Republic
| | - František Odstrčil
- Department of Radiology, Faculty Hospital Olomouc, I. P. Pavlova 6, 77520 Olomouc, Czech Republic
| | - Jan Mareš
- Department of Neurology, Faculty of Medicine and Dentistry, Palacky University and Faculty Hospital Olomouc, I. P. Pavlova 6, 77520 Olomouc, Czech Republic
| | - Petr Kaňovský
- Department of Neurology, Faculty of Medicine and Dentistry, Palacky University and Faculty Hospital Olomouc, I. P. Pavlova 6, 77520 Olomouc, Czech Republic
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47
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Newbould RD, Nicholas R, Thomas CL, Quest R, Lee JSZ, Honeyfield L, Colasanti A, Malik O, Mattoscio M, Matthews PM, Sormani MP, Waldman AD, Muraro PA. Age independently affects myelin integrity as detected by magnetization transfer magnetic resonance imaging in multiple sclerosis. NEUROIMAGE-CLINICAL 2014; 4:641-8. [PMID: 24936415 PMCID: PMC4053639 DOI: 10.1016/j.nicl.2014.02.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 01/23/2014] [Accepted: 02/14/2014] [Indexed: 11/25/2022]
Abstract
Background Multiple sclerosis (MS) is a heterogeneous disorder with a progressive course that is difficult to predict on a case-by-case basis. Natural history studies of MS have demonstrated that age influences clinical progression independent of disease duration. Objective To determine whether age would be associated with greater CNS injury as detected by magnetization transfer MRI. Materials and methods Forty MS patients were recruited from out-patient clinics into two groups stratified by age but with similar clinical disease duration as well as thirteen controls age-matched to the older MS group. Images were segmented by automated programs and blinded readers into normal appearing white matter (NAWM), normal appearing gray matter (NAGM), and white matter lesions (WMLs) and gray matter lesions (GMLs) in the MS groups. WML and GML were delineated on T2-weighted 3D fluid-attenuated inversion recovery (FLAIR) and T1 weighted MRI volumes. Mean magnetization transfer ratio (MTR), region volume, as well as MTR histogram skew and kurtosis were calculated for each region. Results All MTR measures in NAGM and MTR histogram metrics in NAWM differed between MS subjects and controls, as expected and previously reported by several studies, but not between MS groups. However, MTR measures in the WML did significantly differ between the MS groups, in spite of no significant differences in lesion counts and volumes. Conclusions Despite matching for clinical disease duration and recording no significant WML volume difference, we demonstrated strong MTR differences in WMLs between younger and older MS patients. These data suggest that aging-related processes modify the tissue response to inflammatory injury and its clinical outcome correlates in MS. Magnetization transfer MRI was used in a cohort of 40 MS subjects differing by age. MTR metrics were different between MS groups and controls, as expected. MTR in normal appearing tissue did not differ between age-stratified MS groups. MTR in white matter lesions was strongly different between age-stratified MS groups. Results imply an age-related effect in tissue integrity in MR-visible lesions.
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Affiliation(s)
- R D Newbould
- Imanova Centre for Imaging Sciences, London, UK ; Division of Experimental Medicine, Imperial College London, UK
| | - R Nicholas
- Division of Brain Sciences, Imperial College London, UK
| | - C L Thomas
- Division of Brain Sciences, Imperial College London, UK
| | - R Quest
- Department of Imaging, Imperial College Healthcare NHS Trust, UK
| | - J S Z Lee
- Division of Brain Sciences, Imperial College London, UK
| | - L Honeyfield
- Department of Imaging, Imperial College Healthcare NHS Trust, UK
| | - A Colasanti
- Imanova Centre for Imaging Sciences, London, UK ; Division of Brain Sciences, Imperial College London, UK
| | - O Malik
- Division of Brain Sciences, Imperial College London, UK
| | - M Mattoscio
- Division of Brain Sciences, Imperial College London, UK
| | - P M Matthews
- Division of Brain Sciences, Imperial College London, UK ; Neurosciences, GlaxoSmithKline Research and Development, UK
| | - M P Sormani
- Department of Health Sciences (DISSAL), University of Genoa, Italy
| | - A D Waldman
- Division of Brain Sciences, Imperial College London, UK ; Department of Imaging, Imperial College Healthcare NHS Trust, UK
| | - P A Muraro
- Division of Brain Sciences, Imperial College London, UK ; Department of Clinical Neurosciences, Imperial College Healthcare NHS Trust, UK
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Dagley LF, Emili A, Purcell AW. Application of quantitative proteomics technologies to the biomarker discovery pipeline for multiple sclerosis. Proteomics Clin Appl 2014; 7:91-108. [PMID: 23112123 DOI: 10.1002/prca.201200104] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Revised: 10/04/2012] [Accepted: 10/11/2012] [Indexed: 11/08/2022]
Abstract
Multiple sclerosis is an inflammatory-mediated demyelinating disorder most prevalent in young Caucasian adults. The various clinical manifestations of the disease present several challenges in the clinic in terms of diagnosis, monitoring disease progression and response to treatment. Advances in MS-based proteomic technologies have revolutionized the field of biomarker research and paved the way for the identification and validation of disease-specific markers. This review focuses on the novel candidates discovered by the application of quantitative proteomics to relevant disease-affected tissues in both the human context and within the animal model of the disease known as experimental autoimmune encephalomyelitis. The role of targeted MS approaches for biomarker validation studies, such as multiple reaction monitoring will also be discussed.
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Affiliation(s)
- Laura F Dagley
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, Australia
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49
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Swanton J, Fernando K, Miller D. Early prognosis of multiple sclerosis. HANDBOOK OF CLINICAL NEUROLOGY 2014; 122:371-91. [DOI: 10.1016/b978-0-444-52001-2.00015-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
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Filippi M, Charil A, Rovaris M, Absinta M, Rocca MA. Insights from magnetic resonance imaging. HANDBOOK OF CLINICAL NEUROLOGY 2014; 122:115-149. [PMID: 24507516 DOI: 10.1016/b978-0-444-52001-2.00006-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Recent years have witnessed impressive advancements in the use of magnetic resonance imaging (MRI) for the assessment of patients with multiple sclerosis (MS). Complementary to the clinical evaluation, conventional MRI (cMRI) provides crucial pieces of information for the diagnosis of MS, the understanding of its natural history, and monitoring the efficacy of experimental treatments. Measures derived from cMRI present clear advantages over the clinical assessment, including their more objective nature and an increased sensitivity to MS-related changes. However, the correlation between these measures and the clinical manifestations of the disease remains weak, and this can be explained, at least partially, by the limited ability of cMRI to characterize and quantify the heterogeneous features of MS pathology. Quantitative MR-based techniques have the potential to overcome the limitations of cMRI. Magnetization transfer MRI, diffusion-weighted and diffusion tensor MRI with fiber tractography, proton magnetic resonance spectroscopy, T1 and T2 relaxation time measurement, and functional MRI are contributing to elucidate the mechanisms that underlie injury, repair, and functional adaptation in patients with MS. All conventional and nonconventional MR techniques will benefit from the use of high-field MR systems (3.0T or more).
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Affiliation(s)
- Massimo Filippi
- Neuroimaging Research Unit, Department of Neurology, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy.
| | - Arnaud Charil
- Neuroimaging Research Unit, Department of Neurology, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Marco Rovaris
- Neuroimaging Research Unit, Department of Neurology, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Martina Absinta
- Neuroimaging Research Unit, Department of Neurology, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Maria Assunta Rocca
- Neuroimaging Research Unit, Department of Neurology, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
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