Moyamoya disease initially presenting visual field defect.

Progressive narrowing of distal carotid arteries and the development of compensatory fine networks are the characteristic findings of moyamoya disease. Cerebral infarction in moyamoya disease is due to a decreased blood flow and shows an uneven distribution in the distal bed of the anterior and middle cerebral arteries. The progression of disease in the posterior circulation follows that in the anterior circulation. Posterior circulation symptoms due to cerebral infarction usually occur in the advanced stage of the disease and follow the anterior circulation symptoms. We encountered an unusual case of moyamoya disease which initially presented with a transient visual field defect. One month later our patient developed blindness and her cerebral angiography showed advanced moyamoya disease.