title: Cerebral hemodynamics in symptomatic and asymptomatic patients with severe unilateral carotid stenosis before and after carotid endarterectomy.
abstract: BACKGROUND
  Data concerning hemodynamic status prior to and after carotid endarterectomy (CEA) in symptomatic and asymptomatic patients is insufficient. Transcranial Doppler (TCD) provides information regarding compensatory collateral flow as well as mechanisms of cerebral autoregulation in patients with carotid stenosis.
  
  
  METHODS
  Forty eight symptomatic and 81 asymptomatic patients with unilateral severe carotid stenosis were examined by TCD before and in early postoperative period after CEA.
  
  
  RESULTS
  Cigarette smoking was the only risk factor significantly more frequent in symptomatic patients. Preoperative anterior cerebral artery (ACA) and middle cerebral artery (MCA) asymmetry, basilar artery velocity and number of ophthalmic arteries with reversed flow, were not significantly different between the two groups. Pulsatility index, cerebrovascular reactivity and flow acceleration on the side of stenosis were significantly lower in symptomatic patients. After surgery there was a significant improvement of all TCD parameters in symptomatic as well as asymptomatic patients.
  
  
  CONCLUSIONS
  The exhausted ability of cerebral autoregulation is an important factor differentiating between symptomatic and asymptomatic patients with severe carotid stenosis. Successful surgery provides good recovery of cerebral hemodynamics in both symptomatic and asymptomatic patients.
authors.affiliation: Department of Neurology, Rambam Medical Center, P.O.B 9602, 31096 Haifa, Israel. g_telman@rambam.health.gov.il
authors.forename: G
authors.initials: G
authors.lastname: Telman
authors.forename: E
authors.initials: E
authors.lastname: Kouperberg
authors.forename: S
authors.initials: S
authors.lastname: Nitecki
authors.forename: T
authors.initials: T
authors.lastname: Karram
authors.forename: H A
authors.initials: HA
authors.lastname: Schwarz
authors.forename: E
authors.initials: E
authors.lastname: Sprecher
authors.forename: A
authors.initials: A
authors.lastname: Hoffman
authors.forename: D
authors.initials: D
authors.lastname: Yarnitsky
mesh_terms: D000368:Aged; D001488:Basilar Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D001783:Blood Flow Velocity; D002343:Carotid Artery, Internal; D016893:Carotid Stenosis / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery; D002536:Cerebral Arteries / Q000000981:diagnostic imaging / Q000503:physiopathology; D002560:Cerebrovascular Circulation; D003097:Collateral Circulation; D016894:Endarterectomy, Carotid; D005260:Female; D006801:Humans; D008297:Male; D017585:Ultrasonography, Doppler, Transcranial