Serial angiography in a spontaneous dissecting anterior cerebral artery aneurysm.

Intracranial dissecting aneurysms are uncommon, and little is known concerning the natural history of these lesions. In this paper we present a rare case of dissecting aneurysm of the anterior cerebral artery in which a true diagnostic sign of "double lumen" was demonstrated. Sequential changes in angiographic features shown on serial angiographic studies are described, and diagnosis is briefly discussed.