Moyamoya disease: a case of vanishing cerebral vessels.

PURPOSE: To provide an overview of moyamoya disease (MMD) including pathophysiology, epidemiology, clinical presentation, diagnosis, treatment, and prognosis.

DATA SOURCES: Selected clinical and epidemiological studies, review articles, and diagnostic guidelines for MMD.

CONCLUSIONS

MMD is a rare cerebrovascular disease characterized by progressive stenosis of the distal internal carotid arteries and their major branches. The dilated and fragile basal collateral circulations display a "puff of smoke" appearance and thus are called moyamoya vessels. Other unique features of MMD include 2:1 female preponderance and its peak incidence in two age groups: early childhood and adults in their mid-40s. The pathophysiology of MMD is unclear and possible causes include genetic linkage, angiogenesis, autoimmune disease, cranial radiation, and infection of the head and neck. Most patients are symptomatic and may present with ischemic or hemorrhagic strokes, seizure, or headache. The diagnosis depends on clinical presentation and radiographic imaging, and disease progression may be halted with direct or indirect cerebral revascularization.

IMPLICATIONS FOR PRACTICE: It is important to make a correct diagnosis and provide appropriate treatment to reduce the morbidity and mortality associated with MMD. A prompt referral for possible surgical revascularization offers the best chance to reduce additional cerebral injuries and improve clinical outcomes.