Vasculitis presenting as primary leptomeningeal enhancement with minimal parenchymal findings.

In this case of biopsy-proved granulomatous angiitis, MR showed prominent leptomeningeal enhancement with comparatively little parenchymal involvement. Pathologically, granulomatous angiitis chiefly affects small vessels, with a predilection for those in the leptomeninges. Although marked leptomeningeal enhancement is not the most common finding, vasculitis should be added to the differential diagnosis of this MR appearance.