title: Clinical features and outcome in North American adults with moyamoya phenomenon.
abstract: OBJECTIVE
  To describe baseline clinical features and outcomes of adults with moyamoya phenomenon treated at a single North American institution.
  
  
  METHODS
  We identified 34 adults with moyamoya phenomenon by review of angiographic records. Clinical presentation and baseline stroke risk factors were obtained by chart review. Follow-up was obtained prospectively. A 5-year Kaplan-Meier stroke risk was calculated.
  
  
  RESULTS
  The median age was 42 (range 20 to 79) years. Twenty-five were women. The initial symptom was ischemia, hemorrhage, or asymptomatic in 24, 7, and 3 patients, respectively. Twenty-two had bilateral involvement and 12 had unilateral moyamoya vessels. Baseline stroke risk factors were similar between groups. The median follow-up in 31 living patients was 5.1 (range 0.2 to 19.6) years. Fourteen patients were treated with surgical revascularization (20 total hemispheres). In medically treated symptomatic hemispheres, the 5-year risk of recurrent ipsilateral stroke was 65% after the initial symptom and 27% after angiographic diagnosis. Patients with bilateral involvement presenting with ischemic symptoms were at the highest risk of subsequent stroke (n=17, 5-year risk of stroke with medical treatment after first symptom of 82%). In surgically treated hemispheres, the 5-year risk of perioperative or subsequent ipsilateral stroke or death was 17%. This was significantly different compared with medical treatment after first symptom (P=0.02) but not after angiographic diagnosis.
  
  
  CONCLUSIONS
  Moyamoya phenomenon in North American adults is associated with a high risk of recurrent stroke, particularly those with bilateral involvement and ischemic symptoms. These data suggest a potential benefit with surgery if diagnosis could be made earlier.
authors.affiliation: Interventional Neuroradiology Section, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO 63110, USA.
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Hallemeier
authors.forename: Keith M
authors.initials: KM
authors.lastname: Rich
authors.forename: Robert L
authors.initials: RL
authors.lastname: Grubb
authors.forename: Michael R
authors.initials: MR
authors.lastname: Chicoine
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Moran
authors.forename: DeWitte T
authors.initials: DT
authors.lastname: Cross
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Zipfel
authors.forename: Ralph G
authors.initials: RG
authors.lastname: Dacey
authors.forename: Colin P
authors.initials: CP
authors.lastname: Derdeyn
mesh_terms: D000328:Adult; D000368:Aged; D002545:Brain Ischemia / Q000209:etiology*; D002543:Cerebral Hemorrhage / Q000209:etiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009072:Moyamoya Disease / Q000150:complications* / Q000401:mortality / Q000503:physiopathology* / Q000628:therapy; D011446:Prospective Studies; D012008:Recurrence; D012307:Risk Factors; D020521:Stroke / Q000209:etiology; D016019:Survival Analysis; D016896:Treatment Outcome; D014656:Vascular Surgical Procedures