Laura E Jonkman1, Lazar Fleysher2, Martijn D Steenwijk3, Jan A Koeleman4, Teun-Pieter de Snoo4, Frederik Barkhof5, Matilde Inglese6, Jeroen Jg Geurts4. 1. Department of Anatomy & Neurosciences, VU University Medical Center, Amsterdam, The Netherlands le.jonkman@vumc.nl. 2. Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA. 3. Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands/Department of Physics and Medical Technology, VU University Medical Center, Amsterdam, The Netherlands. 4. Department of Anatomy & Neurosciences, VU University Medical Center, Amsterdam, The Netherlands. 5. Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands. 6. Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA/Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA/Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DINOGMI), University of Genoa, Genoa, Italy.
Abstract
BACKGROUND: Cortical gray matter (GM) demyelination is frequent and clinically relevant in multiple sclerosis (MS). Quantitative magnetic resonance imaging (qMRI) sequences such as magnetization transfer ratio (MTR) and quantitative R2* (qR2*) can capture pathological subtleties missed by conventional magnetic resonance imaging (MRI) sequences. Although differences in MTR and qR2* have been reported between lesional and non-lesional tissue, differences between lesion types or lesion types and myelin density matched normal-appearing gray matter (NAGM) have not been found or investigated. OBJECTIVE: Identify quantitative differences in histopathologically verified GM lesion types and matched NAGM at ultra-high field strength. METHODS: Using 7T post-mortem MRI, MRI lesions were marked on T2 images and co-registered to the calculated MTR and qR2* maps for further evaluation. In all, 15 brain slices were collected, containing a total of 74 cortical GM lesions and 45 areas of NAGM. RESULTS: Intracortical lesions had lower MTR and qR2* values compared to NAGM. Type I lesions showed lower MTR than type III lesions. Type III lesions showed lower MTR than matched NAGM, and type I and IV lesions showed lower qR2* than matched NAGM. CONCLUSION: qMRI at 7T can provide additional information on extent of cortical pathology, especially concerning subpial lesions. This may be relevant for monitoring disease progression and potential treatment effects.
BACKGROUND: Cortical gray matter (GM) demyelination is frequent and clinically relevant in multiple sclerosis (MS). Quantitative magnetic resonance imaging (qMRI) sequences such as magnetization transfer ratio (MTR) and quantitative R2* (qR2*) can capture pathological subtleties missed by conventional magnetic resonance imaging (MRI) sequences. Although differences in MTR and qR2* have been reported between lesional and non-lesional tissue, differences between lesion types or lesion types and myelin density matched normal-appearing gray matter (NAGM) have not been found or investigated. OBJECTIVE: Identify quantitative differences in histopathologically verified GM lesion types and matched NAGM at ultra-high field strength. METHODS: Using 7T post-mortem MRI, MRI lesions were marked on T2 images and co-registered to the calculated MTR and qR2* maps for further evaluation. In all, 15 brain slices were collected, containing a total of 74 cortical GM lesions and 45 areas of NAGM. RESULTS: Intracortical lesions had lower MTR and qR2* values compared to NAGM. Type I lesions showed lower MTR than type III lesions. Type III lesions showed lower MTR than matched NAGM, and type I and IV lesions showed lower qR2* than matched NAGM. CONCLUSION: qMRI at 7T can provide additional information on extent of cortical pathology, especially concerning subpial lesions. This may be relevant for monitoring disease progression and potential treatment effects.
Authors: Suzan Maleki; Yann Chye; Xiaoliu Zhang; Linden Parkes; Samuel R Chamberlain; Leonardo F Fontenelle; Leah Braganza; George Youssef; Valentina Lorenzetti; Ben J Harrison; Murat Yücel; Chao Suo Journal: Psychiatry Res Neuroimaging Date: 2020-02-11 Impact factor: 2.376
Authors: Jonathan O'Muircheartaigh; Irene Vavasour; Emil Ljungberg; David K B Li; Alexander Rauscher; Victoria Levesque; Hideki Garren; David Clayton; Roger Tam; Anthony Traboulsee; Shannon Kolind Journal: Hum Brain Mapp Date: 2019-01-15 Impact factor: 5.038