title: Carotid perfusion CT with balloon occlusion and acetazolamide challenge test: feasibility.
abstract: Carotid balloon test occlusion (BTO) is used to assess the collateral circulation and cerebrovascular reserve in patients in whom carotid artery occlusion is contemplated. Eight patients in whom the test was successful were evaluated with perfusion computed tomography (CT) in the resting state and after acetazolamide challenge. Three of the patients showed symmetric blood flow and normal response to acetazolamide. One of them underwent permanent carotid occlusion and did not develop any delayed ischemic stroke. The remaining five patients showed asymmetric blood flow. One of them had markedly low blood flow and abnormal response to acetazolamide. The patient developed ipsilateral hemispheric stroke following permanent carotid occlusion after the superficial temporal artery to middle cerebral artery bypass graft occluded. In the other four patients, the steal phenomenon was seen in ipsilateral and contralateral hemispheres. Although definitive quantitative values for perfusion CT are not yet standardized, it may be feasible to predict that the patients with symmetric blood flow and normal acetazolamide-enhanced challenge test results will do well after permanent carotid occlusion. Patients with asymmetric blood flow and abnormal response to the acetazolamide challenge test may require a revascularization procedure to protect them from delayed ischemic stroke.
authors.affiliation: Department of Radiology, University of Michigan Health System, University Hospital UH B2 A209, 1500 E Medical Center Drive, Ann Arbor, MI 48109, USA.
authors.forename: Rajan
authors.initials: R
authors.lastname: Jain
authors.forename: Ellen G
authors.initials: EG
authors.lastname: Hoeffner
authors.forename: John P
authors.initials: JP
authors.lastname: Deveikis
authors.forename: Mark R
authors.initials: MR
authors.lastname: Harrigan
authors.forename: B Gregory
authors.initials: BG
authors.lastname: Thompson
authors.forename: Suresh K
authors.initials: SK
authors.lastname: Mukherji
mesh_terms: D000086:Acetazolamide / Q000494:pharmacology; D000328:Adult; D021721:Balloon Occlusion; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging*; D002560:Cerebrovascular Circulation / Q000187:drug effects; D003097:Collateral Circulation; D003287:Contrast Media; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D020521:Stroke / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media; D000086:Acetazolamide