title: Time course of cerebral hemodynamics in aneurysmal subarachnoid hemorrhage.
abstract: BACKGROUND
  Vascular complications are important causes of neurologic sequelae among survivors of aneurysmal subarachnoid hemorrhage (SAH). However, little is known about the time course of cerebral hemodynamics and outcome in patients with and without angiographically confirmed cerebral vasospasm.
  
  
  METHODS
  Serial transcranial color-coded sonography (TCCS), angiography, and MRI studies were performed to measure cerebrovascular hemodynamics and assess complications following aneurysmal SAH.
  
  
  RESULTS
  Eighteen aneurysmal SAH patients were enrolled. Angiographically confirmed cerebral vasospasm occurred in 14 patients (77.8%), 5 of whom (35.7%) were asymptomatic. The mean blood flow velocity (V(mean) ) of the middle cerebral artery increased significantly as compared with healthy volunteers from day 1 to day 15, and substantially decreased thereafter. The V(mean) of middle cerebral artery was significantly higher in patients with than in patients without angiographically confirmed cerebral vasospasm from day 3 to day 12. Compared to angiography, TCCS detected cerebral vasospasm with 85.7% sensitivity, 100% specificity, 100% positive predictive value, and 66.7% negative predictive value. MRI-evidenced cerebral infarctions occurred in nine patients (50%), three of whom (33.3%) were asymptomatic.
  
  
  CONCLUSIONS
  This study demonstrated that approximately one-third of acute phase aneurysmal SAH patients have asymptomatic delayed cerebral infarction, which was undetected by TCCS in one-third of them. This may explain why the accuracy of TCCS to predict clinical symptomatic cerebral vasospasm is suboptimal.
authors.affiliation: Department of Neurosurgery, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Hung-Chen
authors.initials: HC
authors.lastname: Wang
authors.forename: Wei-Che
authors.initials: WC
authors.lastname: Lin
authors.forename: Tzu-Ming
authors.initials: TM
authors.lastname: Yang
authors.forename: Wu-Fu
authors.initials: WF
authors.lastname: Chen
authors.forename: Yu-Jun
authors.initials: YJ
authors.lastname: Lin
authors.forename: Nai-Wen
authors.initials: NW
authors.lastname: Tsai
authors.forename: Wen-Neng
authors.initials: WN
authors.lastname: Chang
authors.forename: Cheng-Hsien
authors.initials: CH
authors.lastname: Lu
mesh_terms: D000328:Adult; D000368:Aged; D002533:Cerebral Angiography; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging* / Q000503:physiopathology; D013997:Time Factors; D017585:Ultrasonography, Doppler, Transcranial / Q000379:methods*; D020301:Vasospasm, Intracranial / Q000000981:diagnostic imaging* / Q000503:physiopathology