moyamoya disease
Pronunciation: moy-ah-moy-ah
A progressive cerebrovascular disorder characterized by narrowing of major brain arteries and formation of abnormal collateral blood vessels.
Full Definition
Moyamoya disease is a rare, progressive cerebrovascular disorder characterized by bilateral stenosis or occlusion of the terminal portion of the internal carotid arteries and the proximal portions of the anterior and middle cerebral arteries. In response to this narrowing, abnormal collateral blood vessels develop at the base of the brain, creating a characteristic 'puff of smoke' appearance on angiography (moyamoya means 'puff of smoke' in Japanese). The condition can present in both pediatric and adult populations, with children more commonly experiencing ischemic strokes and adults experiencing hemorrhagic strokes. In pediatric patients, symptoms may include transient ischemic attacks, strokes, seizures, and cognitive decline. Treatment typically involves surgical revascularization procedures.
Usage
Usage note: Japanese term; lowercase unless beginning a sentence.
In Context
- "Cerebral angiography revealed the characteristic moyamoya collateral vessels at the base of the brain." — Neuroradiology report
- "The child underwent bilateral revascularization surgery for symptomatic moyamoya disease." — Neurosurgical procedure note