Serial angiography in isolated angiitis of the central nervous system

Isolated angiitis of the CNS is a disease of unknown etiology characterized by signs and symptoms of diffuse ischemia or recurrent strokes and histologic evidence of vascular inflammation. Angiography frequently suggests the diagnosis, but angiographic changes over time have not been delineated. This study investigates the evolution of radiographic findings in CNS vasculitis by serial angiography in 19 patients. Abnormal angiographic findings include segmental arterial narrowings and dilatations, vascular occlusions, collateral formation, and prolonged circulation time. Smooth narrowings of the affected vessels occurring in multiple vascular distributions are the most frequent abnormality. Single stenotic areas in multiple vessels are more frequent than multiple stenotic areas along a single vessel segment. Vascular occlusions, the least diagnostic feature, affect small arteries in some patients. Serial studies demonstrate progression of angiographic changes prior to therapy and improvement or stabilization in patients with a clinical response to therapy. Correlation of clinical and angiographic features is consistent with the hypothesis that segmental narrowing initially results from reversible inflammation and vasospasm. The later irreversible angiographic features appear secondary to scarring. A limitation of angiography is demonstrated in this study by the apparently normal angiograms in two patients with biopsy-confirmed small-vessel vasculitis. Four patients with abnormal angiograms and histologic evidence of disease had normal MRIs.