title: Intraoperative microemboli and low middle cerebral artery blood flow velocity are additive in predicting development of cerebral ischemic events after carotid endarterectomy.
abstract: OBJECTIVE
  Microemboli generated during dissection of the carotid arteries in patients undergoing carotid endarterectomy result in postoperative cerebral ischemic events. The purpose of this study was to determine whether these events correlate with middle cerebral artery blood flow velocity.
  
  
  METHODS
  One hundred sixty-three patients with ipsilateral internal carotid artery stenosis (>70%) underwent carotid endarterectomy under transcranial Doppler monitoring of mean blood flow velocity and microembolic signals in the ipsilateral middle cerebral artery.
  
  
  RESULTS
  Logistic regression analysis of several variables demonstrated that only middle cerebral artery mean blood flow velocity during carotid dissection was significantly associated with new postoperative neurological deficits in patients with microembolic signals during carotid dissection (95% CI, 1.069 to 1.528; P=0.0072). The combination of low middle cerebral artery mean blood flow velocity (<or=28 cm/s) and microembolic signals >or=10 during carotid dissection resulted in improved specificity and positive predictive value for the development of new postoperative neurological deficits when compared with either criterion used alone.
  
  
  CONCLUSIONS
  Intraoperative microemboli and low middle cerebral artery mean blood flow velocity are additive in predicting the development of cerebral ischemic events after carotid endarterectomy.
authors.affiliation: Department of Neurosurgery, School of Medicine, Iwate Medical University, Morioka, Japan. kuogasa@iwate-med.ac.jp
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Ogasawara
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Suga
authors.forename: Makoto
authors.initials: M
authors.lastname: Sasaki
authors.forename: Kohei
authors.initials: K
authors.lastname: Chida
authors.forename: Masakazu
authors.initials: M
authors.lastname: Kobayashi
authors.forename: Kenji
authors.initials: K
authors.lastname: Yoshida
authors.forename: Yasunari
authors.initials: Y
authors.lastname: Otawara
authors.forename: Akira
authors.initials: A
authors.lastname: Ogawa
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity; D002545:Brain Ischemia / Q000209:etiology*; D016894:Endarterectomy, Carotid / Q000009:adverse effects*; D006801:Humans; D020766:Intracranial Embolism / Q000150:complications / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000473:pathology / Q000502:physiology; D017585:Ultrasonography, Doppler, Transcranial