[Magnetic resonance imaging in moyamoya disease]

Ten patients, seven children and three adults, with "moyamoya" disease were examined by MR-CT. MRI findings in these patients were compared with X-ray CT findings to study the features of the ischemic lesions in "moyamoya" disease and the following results were obtained. Old cerebral infarct, cortical atrophy and intracerebral hematoma in "moyamoya" disease were better delineated by image of the spin echo method. It is possible to differentiate the ischemic lesions such as ischemic edema, or acute or chronic cerebral infarct by calculating the T1 and T2 value from the T1 and T2 image. Ischemic lesions in "moyamoya" disease most often occurred in the watershed area of the anterior cerebral artery-middle cerebral artery or the middle cerebral artery-posterior cerebral artery, and these ischemic lesions were classified into three types according to the location of the lesion, i.e. cortical ischemic, subcortical ischemic and combined type. "Moyamoya" disease in the advanced stage, which was often seen in children, showed the combined type with poor outcome. From the above results, it might be concluded that MRI is superior to X-ray CT as a diagnostic aid to detect ischemic lesions in "moyamoya" disease.