title: Perfusion-weighted magnetic resonance imaging used in assessing hemodynamics following superficial temporal artery-middle cerebral artery bypass in patients with Moyamoya disease.
abstract: BACKGROUND
  The best strategy to assess the changes in brain hemodynamics following superficial temporal artery (STA)-middle cerebral artery (MCA) bypass in patients with Moyamoya disease remains unknown. The purpose of the present study was to assess cerebral hemodynamics using perfusion-weighted magnetic resonance imaging (PWI) before and after STA-MCA bypass surgery in patients with Moyamoya disease.
  
  
  METHODS
  STA-MCA bypass surgeries were performed on 23 symptomatic cerebral hemispheres in 21 patients (11 females/10 males, age 11-62 years) with Moyamoya disease due to cerebral ischemic attacks or intracranial hemorrhages. Brain PWI images were obtained in the frontal lobes, the temporal lobes, the occipital lobes, and the basal ganglia before and after STA-MCA bypass surgery. The relative parameters cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) derived from PWI were calculated. All patients underwent CT angiography or MR angiography after surgery in order to confirm the patency of bypass.
  
  
  RESULTS
  According to preoperative PWI, there was significant hypoperfusion in the symptomatic temporal and frontal lobes. According to postoperative PWI, the regional CBF had increased in both the temporal and frontal lobes on the operative side (p < 0.05, versus preoperative data). In the postoperative CBV maps, there was a significant decrease in the occipital lobe on the operative side (p < 0.05, versus preoperative data). The postoperative MTT in the temporal lobe, frontal lobe and basal ganglia area on the operative side was short, relative to the preoperative MTT (p < 0.05). The CT angiography or MR angiography imaging demonstrated patency of the bypass in all patients after surgery. During the follow-up period, all patients showed significant improvement in neurological function postoperatively.
  
  
  CONCLUSIONS
  This study demonstrates that STA-MCA bypass is a safe and effective surgical treatment for Moyamoya disease. PWI enables an effective and objective assessment of hemodynamics before and after STA-MCA bypass surgery in patients with Moyamoya disease.
authors.affiliation: Department of Neurosurgery, Wuhan Medical and Health Center for Women and Children, Wuhan, China.
authors.forename: Zhengwei
authors.initials: Z
authors.lastname: Li
authors.forename: Ping
authors.initials: P
authors.lastname: Zhou
authors.forename: Zhongwei
authors.initials: Z
authors.lastname: Xiong
authors.forename: Zhao
authors.initials: Z
authors.lastname: Ma
authors.forename: Sheng
authors.initials: S
authors.lastname: Wang
authors.forename: Hongqiang
authors.initials: H
authors.lastname: Bian
authors.forename: Jincao
authors.initials: J
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000328:Adult; D001479:Basal Ganglia / Q000098:blood supply; D001783:Blood Flow Velocity; D001810:Blood Volume; D002533:Cerebral Angiography; D002540:Cerebral Cortex / Q000098:blood supply; D002548:Cerebral Revascularization; D002560:Cerebrovascular Circulation; D002648:Child; D005260:Female; D006439:Hemodynamics; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000601:surgery*; D009072:Moyamoya Disease / Q000503:physiopathology* / Q000601:surgery; D013699:Temporal Arteries / Q000000981:diagnostic imaging / Q000601:surgery*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014654:Vascular Patency; D055815:Young Adult