Multiple Sclerosis with Focal Leptomeningeal Enhancement

In multiple sclerosis (MS), the orientation of subpial cortical lesions suggests that demyelination can occur from the surface of the brain. Meningeal inflammation and B-cell follicles are thought to have an underlying role in the formation of subpial lesions. Identifying gadolinium enhancement is difficult because prominent meningeal blood vessels normally appear bright on T1-weighted postcontrast images. To assess for potential leptomeningeal abnormalities in MS, investigators used postcontrast T2 fluid-attenuated inversion recovery magnetic resonance imaging (FLAIR MRI) in 299 patients with MS and 37 healthy controls.

Of the 299 patients, 74 had one or more areas of leptomeningeal enhancement, occurring in 35 of 181 (19%) with relapsing M…