Background and purpose: Previous cross-sectional studies have reported the involvement of thalamus, pallidum, superior cerebellar peduncle, temporal cortex, and fronto-parietal white matter in multiple sclerosis (MS)-related fatigue. However, the longitudinal imaging correlates of fatigue severity variation in MS remain unclear.
Methods: Structural and diffusion tensor imaging (DTI) data were collected from 43 relapsing remitting MS (RRMS) patients with fatigue (Fatigue Severity Scale [FSS] range: 1-7). Subcortical nuclei volume using FreeSurfer and cortical diffusion indices using a cross-modality technique were measured at baseline and year 1.
Results: The pallidal volume had significantly decreased (P = .002) by year 1, although the fatigue score variation was not significant. At year 1, the pallidal volume (P = .023) and fractional anisotropy (FA, P = .013) of right temporal cortex (RTC) correlated significantly with FSS.
Conclusions: The pallidal volume and the FA-RTC may be used to evaluate longitudinal fatigue severity variation. Our study proposes new biomarkers to monitor fatigue severity in MS patients.
Keywords: Fatigue; magnetic resonance imaging; multiple sclerosis; pallidum; temporal lobe.
© 2018 by the American Society of Neuroimaging.