title: Clinical features of moyamoya disease in the United States.
abstract: OBJECTIVE
  We report the clinical features and longitudinal outcome of the largest cohort of patients with moyamoya disease described from a single institution in the western hemisphere. Moyamoya disease in Asia usually presents with ischemic stroke in children and intracranial hemorrhage in adults.
  
  
  METHODS
  Our study population included all patients with moyamoya disease evaluated at a university hospital in Houston, Texas from 1985 through 1995 (n = 35). We used Kaplan-Meier methods to estimate individual and hemispheric stroke risk by treatment status (medical versus surgical). Predictors of neurological outcome were assessed.
  
  
  RESULTS
  The ethnic background of our patients was representative of the general population in Texas. The mean age at diagnosis was 32 years (range, 6 to 59 years). Ischemic stroke or transient ischemic attack was the predominant initial symptom in both adults and children. Of the 6 patients with intracranial hemorrhage, 5 had an intraventricular site of hemorrhage. The crude stroke recurrence rate was 10.3% per year in 116 patient-years of follow-up. Twenty patients underwent surgical revascularization, the most common procedure being encephaloduroarteriosynangiosis. The 5-year risk of ipsilateral stroke after synangiosis was 15%, compared with 20% for medical treatment and 22% overall for surgery.
  
  
  CONCLUSIONS
  Our observations indicate that moyamoya disease may have a different clinical expression in the United States than in Asia, and may demonstrate a trend toward a lower stroke recurrence rate and better functional outcome after synangiosis.
authors.affiliation: Department of Neurology, Baylor College of Medicine, Houston, Tex 77030, USA. dchiu@bcm.tmc.edu
authors.forename: D
authors.initials: D
authors.lastname: Chiu
authors.forename: P
authors.initials: P
authors.lastname: Shedden
authors.forename: P
authors.initials: P
authors.lastname: Bratina
authors.forename: J C
authors.initials: JC
authors.lastname: Grotta
mesh_terms: D000293:Adolescent; D000328:Adult; D002545:Brain Ischemia / Q000209:etiology; D002543:Cerebral Hemorrhage / Q000209:etiology; D002548:Cerebral Revascularization; D002561:Cerebrovascular Disorders / Q000209:etiology; D002648:Child; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D002546:Ischemic Attack, Transient / Q000209:etiology; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009072:Moyamoya Disease / Q000150:complications / Q000503:physiopathology* / Q000601:surgery; D012008:Recurrence; D016019:Survival Analysis; D016896:Treatment Outcome; D014481:United States