title: Brain computed tomography perfusion may help to detect hemodynamic reconstitution and predict intracerebral hemorrhage after carotid stenting.
abstract: OBJECTIVE
  We wanted to examine whether brain computed tomography (CT) perfusion can help to detect the reconstitution of cerebral hemodynamics and predict intracerebral hemorrhage (ICH) after carotid stenting.
  
  
  METHODS
  From September 2002 to October 2009, data of 114 patients with carotid intervention were prospectively collected, and we retrospectively identified a total of 108 consecutive patients with unilateral carotid stenting. Brain CT perfusion was studied at three time points: 1 week before, and 1 week and 6 months after stenting. Cerebral blood volume (CBV), cerebral blood flow, and time to peak (TTP) of brain CT perfusion were examined at cortical and subcortical areas of middle cerebral artery (MCA) and posterior cerebral artery territory. The CBV, cerebral blood flow, and TTP ratios of stenting side/nonstenting side were used for comparison. The flow direction of ophthalmic artery was detected by sonography, and the presence of anterior communicating artery was examined on prestenting cerebral angiogram.
  
  
  RESULTS
  After carotid stenting, CBV and TTP ratios improved significantly in both MCA cortical and subcortical areas in patients with unilateral carotid stenosis (P < .01) but not in patients with bilateral carotid stenosis. Patients with reversed ophthalmic flow had better improvement of TTP in both MCA and posterior cerebral artery territories (P < .05) than patients with forward flow. However, no significant difference was found between patients with and patients without anterior communicating artery collateral (P > .05). The prestenting TTP ratio in MCA subcortical area was significantly higher in patients with poststenting ICH than patients without ICH (P = .0191).
  
  
  CONCLUSIONS
  Cerebral hemodynamics can be reconstituted within a few days after carotid revascularization, especially in patients with reversed ophthalmic flow. Prolonged TTP in prestenting MCA subcortical area may suggest a high risk of poststenting ICH.
authors: Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital, Linkou Medical Center and Chang Gung University College of Medicine, Taoyuan, Taiwan.
authors: Shy-Chyi
authors: SC
authors: Chin
authors: Chien-Hung
authors: CH
authors: Chang
authors: Ting-Yu
authors: TY
authors: Chang
authors: Ko-Lun
authors: KL
authors: Huang
authors: Tai-Cheng
authors: TC
authors: Wu
authors: Jr-Rung
authors: JR
authors: Lin
authors: Yeu-Jhy
authors: YJ
authors: Chang
authors: Tsong-Hai
authors: TH
authors: Lee
mesh_terms: D000368:Aged; D016893:Carotid Stenosis / Q000601:surgery*; D002543:Cerebral Hemorrhage / Q000000981:diagnostic imaging*; D002560:Cerebrovascular Circulation; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D059906:Neuroimaging; D011183:Postoperative Complications / Q000000981:diagnostic imaging*; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D015607:Stents; D014057:Tomography, X-Ray Computed