INTRACRANIAL ANEURYSMS IN MOYAMOYA DISEASE - REPORT OF 10 CASES AND REVIEW OF THE LITERATURE

The occurrence of unilateral and bilateral moyamoya disease may be ass ociated with intracranial aneurysms. These aneurysms are of two types: major-artery aneurysms and peripheral-artery aneurysms. The former ar ise at the circle of Willis and the latter are located mainly at eithe r the moyamoya vessels or at the choroidal arteries. We analyzed 76 pa tients with cerebral aneurysms associated with moyamoya disease who we re affected unilaterally or bilaterally. Of them, 10 cases were studie d by our group and 66 have been reported in other studies. The charact eristics of the aneurysms were assessed. The frequency of aneurysms as sociated with moyamoya is 4-fold higher in unilateral than in bilatera l moyamoya. Major-artery aneurysms are found mainly in the arterial co mplex of the anterior communicating artery-anterior cerebral artery in patients with unilateral moyamoya, and in the basilar artery in patie nts with bilateral moyamoya. When microaneurysms are taken into accoun t, peripheral-artery aneurysms are more frequent than major-artery ane urysms. Our results suggest that aneurysms associated with moyamoya di sease have some characteristics that should be taken into consideratio n when making comparisons with these lesions encountered in the genera l population.