title: Normalization of transcranial Doppler middle cerebral artery velocities after aneurysm clipping.
abstract: BACKGROUND
  Factors that promote normalization of middle cerebral artery (MCA) velocities after cerebral aneurysm surgery may be important to identify in order to optimize management. Survival analysis of serial transcranial Doppler (TCD) MCA velocities in the setting of aneurysm surgery offers an additional means of analyzing outcome.
  
  
  METHODS
  We retrospectively studied serial MCA velocities obtained via TCD in 113 patients who underwent cerebral aneurysm clipping to analyze which factors promoted normalization. The presence of bleeding, aneurysm location, age, gender, ethnicity, initial blood pressure, hemoglobin, and clinical condition were examined.
  
  
  RESULTS
  Patients who did not bleed but were clipped still tended to have transient periods of abnormally elevated velocities. Of those patients who bled and were clipped, older patients normalized faster. Women showed a trend toward slower normalization only in the subarachnoid hemorrhage (SAH) absent group. Other parameters listed above did not effect normalization time.
  
  
  CONCLUSIONS
  Our data suggest aneurysm surgery in and of itself may promote transient rises in MCA velocities. Age appears to be a significant factor in predicting normalization of MCA velocities after SAH.
authors.affiliation: Transcranial Doppler Laboratory, University of Illinois College of Medicine, Chicago 60612, USA.
authors.forename: S U
authors.initials: SU
authors.lastname: Brint
authors.forename: W B
authors.initials: WB
authors.lastname: Yoon
authors.forename: D B
authors.initials: DB
authors.lastname: Hier
authors.forename: J I
authors.initials: JI
authors.lastname: Ausman
authors.forename: F
authors.initials: F
authors.lastname: Charbel
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017542:Aneurysm, Ruptured / Q000150:complications / Q000601:surgery; D001783:Blood Flow Velocity; D002536:Cerebral Arteries / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D012016:Reference Values; D012189:Retrospective Studies; D013345:Subarachnoid Hemorrhage / Q000209:etiology; D016896:Treatment Outcome; D017585:Ultrasonography, Doppler, Transcranial