title: Hemodynamic and electrophysiological evaluation following extracranial/intracranial bypass surgery.
abstract: We examined 50 patients with an extracranial/intracranial bypass using transcranial Doppler blood flow mapping, somatosensory evoked potentials, and computer-assisted EEG analysis. The investigation was supplemented by temporary compression of the extracranial supplying vessel. Transcranial Doppler sonography revealed in addition to 4 patients with nonpatent anastomoses, a bypass-mediated retrograde flow in the ipsilateral middle cerebral artery beyond a depth of 40 mm in the majority of patients. In 9 patients, retrograde flow could be demonstrated in the whole proximal (M1) MCA segment. The precommunicating segment of the anterior cerebral artery (A1) could be reliably insonated in all but 5 patients. Bypass-compression dependent alterations in the SSEP and in EEG analysis were only observed in a small number of patients. Transcranial Doppler sonography, with the aid of the flow mapping system, appears therefore, to be a reliable and repeatedly performable noninvasive technique for the assessment of intracranial hemodynamics following bypass surgery.
authors.affiliation: Neurosurgical Clinic, Medical University Hannover, Fed. Rep. of Germany.
authors.forename: G
authors.initials: G
authors.lastname: Dorfmüller
authors.forename: W P
authors.initials: WP
authors.lastname: Sollmann
authors.forename: M
authors.initials: M
authors.lastname: Lorenz
authors.forename: M R
authors.initials: MR
authors.lastname: Gaab
authors.forename: H
authors.initials: H
authors.lastname: Hinrichs
authors.forename: H
authors.initials: H
authors.lastname: Feistner
mesh_terms: D000328:Adult; D000368:Aged; D000714:Anastomosis, Surgical; D001783:Blood Flow Velocity / Q000502:physiology; D001921:Brain / Q000098:blood supply*; D002545:Brain Ischemia / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging / Q000601:surgery; D016893:Carotid Stenosis / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D002548:Cerebral Revascularization; D004453:Echoencephalography / Q000295:instrumentation*; D004569:Electroencephalography / Q000295:instrumentation*; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging / Q000503:physiopathology; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000503:physiopathology*; D011930:Reaction Time / Q000502:physiology; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*