Abstract Details

Title White Matter Tractometry Correlates with Fatigue Severity in Young Adults with Multiple Sclerosis

Topic Multiple Sclerosis

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

Poster/Presentation
Number 9-014

Objective To characterize cerebral white matter (WM) microstructural damage in young adults with relapsing-remitting multiple sclerosis (RRMS) and to assess the relationship between WM abnormalities measured with diffusion-weighted imaging and the severity of cognitive dysfunction, fatigue and depressive symptoms.

Background Cognitive impairment has a high prevalence in RRMS patients and can be present in the first years of the disease. Depression and fatigue are frequent comorbidities and have a significant impact on quality of life. Diffuse WM abnormalities are thought to be involved but the specific pattern of damage remains poorly understood.

Design/Methods Twenty-five RRMS patients and 11 healthy controls (HC), aged between 22 and 37, were studied using cutting-edge diffusion magnetic resonance imaging tractometry. Diffusion metrics were computed using free water correction to obtain tissue-specific measurements. High angular resolution diffusion imaging probabilistic tractography was used. Twelve WM bundles previously reported to be associated with neuropsychological dysfunction in RRMS were studied. The correlation between WM abnormalities in RRMS patients and their score at the Symbol Digit Modalities Test (SDMT), Paced Auditory Serial Addition Test (PASAT-3), Modified Fatigue Impact Scale (French version, EMIF-SEP) and Beck Depression Inventory-II (BDI-II) was investigated.

Results A difference between RRMS patients and the HC was established for the anterior corpus callosum, right cingulum, bilateral inferior fronto-occipital fasciculus, bilateral inferior longitudinal fasciculus, right superior longitudinal fasciculus and left uncinate fasciculus. In the RRMS group, free-water corrected fractional anisotropy was reduced while radial and medial diffusivities were increased. Fatigue severity correlated to diffusion abnormalities of anterior corpus callosum and left inferior longitudinal fasciculus. No correlation was found between imaging results and SDMT, PASAT-3 and BDI-II scores.

Conclusions In young adults with RRMS, fatigue is associated to damage in distinct WM bundles. A bundle-wise approach combined with diffusion metrics is more specific than whole-brain diffusion tensor imaging methods to assess cerebral WM bundles’ function.

Authors/Disclosures
Ann-Marie Beaudoin (Centre Hospitalier Universitaire De Sherbrooke) PRESENTER	No disclosure on file
	No disclosure on file
	No disclosure on file
	No disclosure on file
Albert Lamontagne, MD	No disclosure on file
	No disclosure on file