Moyamoya disease:the values of MR imaging and MR angiography(a report of 16 cases)

Objective:To evaluate MRI and MRA in the diagnosis of moyamoya disease.Methods:MRI and MRA findings and clinical materials of 16 patients with moyamoya disease were retrospectively analyzed.All patients were performed with three dimensional time of flight MRA.Results:The stenosis or/and occlusion of the branches distal from the internal carotid bifurcation in varying degrees were shown on MRA in all cases.MRA also documented the dilated posterior communicating arteries in 17,the dilated ophthalmic arteries in 4 and the anastomoic network in basal ganglia region in 16,of which 6 patients were accompanied by the anastomoic network in posterior basal ganglia area.In addition,MRA showed the increase of leptomeningeal anastomotic branches in 10 patients.MRI demonstrated cerebral hemorrhage or infarction,and numerous spotty flow void effect in basal ganglia region.Conclusion:MRI and MRA are effective and noninvasive methods for the diagnosis of moyamoya disease.They are of great value for the diagnosis,screening,follow up study and postoperative evaluation of moyamoya disease.