Regional brain atrophy evolves differently in patients with multiple sclerosis according to clinical phenotype

Progressive brain atrophy is a well-known feature of multiple sclerosis (MS). We characterized the spatial evolution of atrophy in different MS phenotypes.

Dual-echo and T1-weighted MR images were obtained in 70 patients with MS and 10 healthy control subjects at entry and after 15 months. Within-group changes in regional atrophy were assessed by applying Structural Image Evaluation Using Normalization of Atrophy software and statistical parametric mapping analysis. Reported differences are for P <.001.

During follow-up, patients with relapsing-remitting MS (RRMS) differences significant atrophy around the ventricular system; pericerebellar spaces; cerebellar tentorium; putamen; corpus callosum; cingulate sulcus; hippocampus; parieto-occipital fissure; lateral fissure; and frontal, parietal, temporal, and occipital cortex. Patients with secondary progressive MS developed significant atrophy of the cingulate sulcus; pulvinar; caudate nucleus; anterior orbital gyrus; mammillary body; fourth ventricle; and regions of frontal, parietal, temporal, and occipital cortex. Patients with primary progressive MS developed significant atrophy of the bilateral central sulcus; caudate nucleus; prepontine and quadrigeminal cisterns; lateral ventricle; and regions of frontal, parietal, temporal, and occipital cortex. In all phenotypes, the development of atrophy in some regions was significantly correlated with the accumulation of T2- and T1-visible lesions and clinical disability (r = -0.57 to -0.86).

In MS, brain atrophy develops involving different structures in the different phenotypes. While ventricular enlargement is predominant in RRMS, cortical atrophy seems to be more important in the progressive forms. Measures of regional brain atrophy were significantly correlated with disability, suggesting that this approach is promising for bridging the gap between clinical and MR imaging findings in MS.