Progressive disease that affects the cerebrovascular
circulation. Characterized by narrowing and/or complete obstruction of the
carotids. Clinically, may cause paralysis. Headaches, various vision
problems, mental retardation, and psychiatric problems may occur. Cerebral
hemorrhage (subarachnoid), cerebral infarction, severe headaches, speech
disorders, and sudden onset of recurrent paralysis are part of the
presentation but most often occur in juvenile moyamoya patients. Children
may have convulsions or involuntary movements. Hemianopia, diplopia,
bilateral decreased visual acuity, and inability to recognize objects are
clinical symptoms.