title: Cerebral blood flow response pattern during balloon test occlusion of the internal carotid artery.
abstract: OBJECTIVE
  To evaluate the risk of temporary or permanent internal carotid artery occlusion.
  
  
  METHODS
  In 156 patients intraarterial balloon test occlusion in combination with a stable xenon-enhanced CT cerebral blood flow study was performed before radiologic or surgical treatment. All 156 patients passed the clinical balloon test occlusion and underwent a xenon study in combination with a second balloon test. Quantitative flow data were analyzed for absolute changes as well as changes in symmetry.
  
  
  RESULTS
  Fourteen patients exhibited reduced flow values between 20 and 30 mL/100 g per minute, an absolute decrease in flow, and significant asymmetry in the middle cerebral artery territory during balloon test occlusion. These patients would be considered at high risk for cerebral infarction if internal carotid artery occlusion were to be performed. With one exception they belonged to a group (class I) of 61 patients who showed bilateral or ipsilateral flow decrease and significant asymmetry with lower flow on the side of occlusion. The other 95 patients, who showed a variety of cerebral blood flow response patterns including ipsilateral or bilateral flow increase, were at moderate (class II) or low (class III) stroke risk. In contrast to these findings, exclusively qualitative flow analysis failed to identify the patients at high risk: a threshold with an asymmetry index of 10% revealed only 16% specificity whereas an asymmetry index of 45% showed only 61% sensitivity for detection of low flow areas (< 30 mL/100 g per minute).
  
  
  CONCLUSIONS
  For achieving a minimal hemodynamic related-stroke rate associated with permanent clinical internal carotid artery occlusion we suggest integration of a thorough analysis of quantitative cerebral blood flow data before and during balloon test occlusion.
authors.affiliation: Hannover University, Germany.
authors.forename: J P
authors.initials: JP
authors.lastname: Witt
authors.forename: H
authors.initials: H
authors.lastname: Yonas
authors.forename: C
authors.initials: C
authors.lastname: Jungreis
mesh_terms: D000293:Adolescent; D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology; D001921:Brain / Q000098:blood supply*; D002545:Brain Ischemia / Q000000981:diagnostic imaging; D001932:Brain Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000601:surgery; D002340:Carotid Artery Diseases / Q000000981:diagnostic imaging* / Q000601:surgery; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging / Q000601:surgery; D002404:Catheterization; D002426:Cavernous Sinus / Q000000981:diagnostic imaging / Q000601:surgery; D002544:Cerebral Infarction / Q000000981:diagnostic imaging; D002648:Child; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery; D006801:Humans; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging* / Q000601:surgery; D008297:Male; D008577:Meningeal Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery; D008579:Meningioma / Q000000981:diagnostic imaging / Q000601:surgery; D011183:Postoperative Complications / Q000000981:diagnostic imaging; D012039:Regional Blood Flow / Q000502:physiology; D012307:Risk Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014978:Xenon
chemical_list: D014978:Xenon