Abstract Details

Title Measurement of White Matter Atrophy in Multiple Sclerosis Using Diffusion Weighted Imaging

Topic Multiple Sclerosis

Presentation(s) P1 - Poster Session 1 (12:00 PM-1:00 PM)

Poster/Presentation
Number 9-020

Objective This study aimed at assessing the applicability of the diffusion weighted (DW) constrained spherical deconvolution (CSD) MRI model in multiple sclerosis (MS), and to estimate a measure of WM atrophy for specific fiber bundles.

Background Gray matter is more relevant than white matter (WM) atrophy in explaining clinical disability and cognitive impairment in MS. However, WM is a complex structure whose fiber orientation should be considered when investigating its morphology. CSD is an advanced DWI model that provides an estimate of the distribution of fibers within each imaging voxel, contributing to better characterize regions with crossing-fibers.

Design/Methods Multi-shell DWI and 3D T1-weighted MRI scans were obtained from 45 MS patients and 45 age- and sex-matched healthy controls (HC). To assess the applicability of CSD, we compared the amplitude and directions of fiber orientation density (FOD) distributions between HC and MS, including also for the presence of lesions in the model. The ‘fixel-based morphometry’ was then applied to estimate fiber bundle cross-section (FC) atrophy in MS against HC. Voxel-based analysis of fractional anisotropy (FA) was also performed.

Results Within lesion locations, we found significant differences (p<0.001) of FOD’s amplitude between MS and HC, and between MS patients when including the lesion filling technique (p<0.001). By including lesions in the model, CSD was able to estimate FOD, even if fiber directions were significantly underestimated (p<0.001). The fixel-based morphometry showed a significant reduction of the WM FC in MS compared to HC that was specific for each fiber bundle. Decreases in FA in MS patients compared to HC involved less extensive regions with respect to FC.

Conclusions The multi-shell CSD method proved to be an advanced DW model that could be applied in MS for a fiber-specific study of the WM microstructure and fiber-bundle atrophy quantification, after accounting for the presence of MS lesions within the model.

Authors/Disclosures
Loredana Storelli PRESENTER	Loredana Storelli has nothing to disclose.
Elisabetta Pagani	Elisabetta Pagani has nothing to disclose.
Paolo Preziosa (Ospedale San Raffaele)	Mr. Preziosa has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Bristol Myers Squibb . Mr. Preziosa has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Sanofi Genzyme. Mr. Preziosa has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Novartis. Mr. Preziosa has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Roche. Mr. Preziosa has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Merck.
Federica Esposito	Federica Esposito has received personal compensation in the range of $0-$499 for serving as a Consultant for Merck. Federica Esposito has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Novartis. Federica Esposito has received personal compensation in the range of $0-$499 for serving as a Consultant for Novartis. Federica Esposito has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Novartis. Federica Esposito has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Merck. The institution of Federica Esposito has received research support from Italian MS Society. The institution of Federica Esposito has received research support from Italian Ministry of Health. The institution of Federica Esposito has received research support from ERA Net. The institution of Federica Esposito has received research support from European Commission. Federica Esposito has received intellectual property interests from a discovery or technology relating to health care.
Laura Cacciaguerra, MD, PhD (Mayo Clinic)	Dr. Cacciaguerra has nothing to disclose.
Massimo Filippi, MD, FAAN (Ospedale San Raffaele, Neuroimaging Research Unit)	Dr. Filippi has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Alexion, Almirall, Biogen, Merck, Novartis, Roche, Sanofi. Dr. Filippi has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Alexion, Biogen, Bristol-Myers Squibb, Merck, Novartis, Roche, Sanofi, Sanofi-Aventis, Sanofi-Genzyme, Takeda. Dr. Filippi has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Bayer, Biogen, Celgene, Chiesi Italia SpA, Eli Lilly, Genzyme, Janssen, Merck-Serono, Neopharmed Gentili, Novartis, Novo Nordisk, Roche, Sanofi, Takeda, and TEVA. Dr. Filippi has received personal compensation in the range of $10,000-$49,999 for serving as an Editor, Associate Editor, or Editorial Advisory Board Member for Springer Nature. The institution of Dr. Filippi has received research support from Biogen Idec, Merck-Serono, Novartis, Roche, the Italian Ministry of Health, the Italian Ministry of University and Research, and Fondazione Italiana Sclerosi Multipla.
Maria A. Rocca (Neuroimaging Research Unit)	Maria Assunta Rocca has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Biogen, Bristol Myers Squibb, Eli Lilly, Janssen, Roche. Maria Assunta Rocca has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for AstraZaneca, Biogen, Bristol Myers Squibb, Bromatech, Celgene, Genzyme, Horizon Therapeutics Italy, Merck Serono SpA, Novartis, Roche, Sanofi and Teva. The institution of Maria Assunta Rocca has received research support from MS Society of Canada, the Italian Ministry of Health, the Italian Ministry of University and Research, and Fondazione Italiana Sclerosi Multipla.