title: Assessment of cortical damage in early multiple sclerosis with quantitative T2 relaxometry.
abstract: T2 relaxation time is a quantitative MRI in vivo surrogate of cerebral tissue damage in multiple sclerosis (MS) patients. Cortical T2 prolongation is a known feature in later disease stages, but has not been demonstrated in the cortical normal appearing gray matter (NAGM) in early MS. This study centers on the quantitative evaluation of the tissue parameter T2 in cortical NAGM in a collective of early MS and clinically isolated syndrome (CIS) patients, hypothesizing that T2 prolongation is already present at early disease stages and variable over space, in line with global and focal inflammatory processes in MS. Additionally, magnetization transfer ratio (MTR) mapping was performed for further characterization of the expected cortical T2 alteration. Quantitative T2 and MTR maps were acquired from 12 patients with CIS and early MS, and 12 matched healthy controls. The lesion-free part of the cortical volume was identified, and the mean T2 and MTR values and their standard deviations within the cortical volume were determined. For evaluation of spatial specificity, cortical lobar subregions were tested separately for differences of mean T2 and T2 standard deviation. We detected significantly prolonged T2 in cortical NAGM in patients. T2 prolongation was found across the whole cerebral cortex and in all individual lobar subregions. Significantly higher standard deviations across the respective region of interest were found for the whole cerebral cortex and all subregions, suggesting the occurrence of spatially inhomogeneous cortical damage in all regions studied. A trend was observed for MTR reduction and increased MTR variability across the whole cortex in the MS group, suggesting demyelination. In conclusion, our results suggest that cortical damage in early MS is evidenced by spatially inhomogeneous T2 prolongation which goes beyond demyelination. Iron deposition, which is known to decrease T2, seems less prominent.
authors.affiliation: Department of Neurology, Goethe University, Frankfurt/Main, Germany.|Brain Imaging Center, Goethe University, Frankfurt/Main, Germany.
authors.forename: René-Maxime
authors.initials: RM
authors.lastname: Gracien
authors.affiliation: Department of Neurology, Goethe University, Frankfurt/Main, Germany.|Brain Imaging Center, Goethe University, Frankfurt/Main, Germany.
authors.forename: Sarah C
authors.initials: SC
authors.lastname: Reitz
authors.affiliation: Department of Neurology, Goethe University, Frankfurt/Main, Germany.|Brain Imaging Center, Goethe University, Frankfurt/Main, Germany.
authors.forename: Stephanie-Michelle
authors.initials: SM
authors.lastname: Hof
authors.affiliation: Department of Neurology, Johannes Gutenberg University, Mainz, Germany.|Neuroimaging Center (NIC) of the Focus Program Translational Neuroscience (FTN), Johannes Gutenberg-University, Mainz, Germany.
authors.forename: Vinzenz
authors.initials: V
authors.lastname: Fleischer
authors.affiliation: Department of Neurology, Johannes Gutenberg University, Mainz, Germany.|Neuroimaging Center (NIC) of the Focus Program Translational Neuroscience (FTN), Johannes Gutenberg-University, Mainz, Germany.
authors.forename: Hilga
authors.initials: H
authors.lastname: Zimmermann
authors.affiliation: Department of Neurology, Johannes Gutenberg University, Mainz, Germany.|Neuroimaging Center (NIC) of the Focus Program Translational Neuroscience (FTN), Johannes Gutenberg-University, Mainz, Germany.
authors.forename: Amgad
authors.initials: A
authors.lastname: Droby
authors.affiliation: Department of Neurology, Goethe University, Frankfurt/Main, Germany.
authors.forename: Helmuth
authors.initials: H
authors.lastname: Steinmetz
authors.affiliation: Department of Neurology, Johannes Gutenberg University, Mainz, Germany.|Neuroimaging Center (NIC) of the Focus Program Translational Neuroscience (FTN), Johannes Gutenberg-University, Mainz, Germany.
authors.forename: Frauke
authors.initials: F
authors.lastname: Zipp
authors.affiliation: Brain Imaging Center, Goethe University, Frankfurt/Main, Germany.
authors.forename: Ralf
authors.initials: R
authors.lastname: Deichmann
authors.affiliation: Department of Neurology, Goethe University, Frankfurt/Main, Germany.|Brain Imaging Center, Goethe University, Frankfurt/Main, Germany.
authors.forename: Johannes C
authors.initials: JC
authors.lastname: Klein
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000473:pathology*; D003710:Demography; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009103:Multiple Sclerosis / Q000473:pathology*
keywords: MTR; T2; cerebral cortex; multiple sclerosis (MS); normal appearing gray matter (NAGM); quantitative MRI (qMRI)