title: Unstable cerebral hemodynamics in carotid artery occlusion and large hemispheric stroke: a cerebral blood flow volume study.
abstract: OBJECTIVE
  In chronic internal carotid artery (ICA) occlusion, cerebral hemodynamics are likely to be stable due to collateral flow. The authors evaluated cerebral hemodynamics in ICA occlusion using the sonographic method of cerebral blood flow volume (CBVF) measurement to find differences that might identify patients with large hemispheric stroke in ICA occlusion.
  
  
  RESULTS
  The ultrasound method of CBVF measurement was used, which represents the sum of flow volumes of both internal carotid and both vertebal arteries. CBVF was measured in 29 patients with ICA occlusion including patients with (1) chronic ICA occlusion without acute minor stroke, (2) chronic ICA occlusion with acute minor stroke, (3) acute minor stroke due to acute ICA occlusion, and (4) ICA occlusion and large hemispheric stroke. In ICA occlusion, overall CBVF is lower compared to healthy volunteers, due to a significant reduction of CBVF in groups 3 and 4. Comparing groups, there were no differences in CBVF between groups 1, 2, and 3. CBVF in group 4 is reduced compared to all other groups. By receiver-operating characteristic analysis, a CBVF cutoff value for large hemispheric stroke was computed with a sensitivity of 100% and a specificity of 95.8%.
  
  
  CONCLUSIONS
  Stroke due to acute ICA occlusion is associated with decreased CBVF compared to chronic ICA occlusion. Moreover, ICA occlusion and large hemispheric stroke are associated with decreased CBVF compared to all other groups, indicating instability of cerebral hemodynamics. CBVF measurement thus may be a useful tool in predicting large middle cerebral artery stroke early in ICA occlusion.
authors.affiliation: Department of Neurology, Universitätsklinikum Hamburg-Eppendorf, Martinistr.52, D-20246, Germany. niesen@uke.unihamburg.de
authors.forename: Wolf-Dirk
authors.initials: WD
authors.lastname: Niesen
authors.forename: Cornelius
authors.initials: C
authors.lastname: Weiller
authors.forename: Ulrich
authors.initials: U
authors.lastname: Sliwka
mesh_terms: D000368:Aged; D001157:Arterial Occlusive Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002343:Carotid Artery, Internal; D016893:Carotid Stenosis / Q000000981:diagnostic imaging / Q000503:physiopathology*; D016022:Case-Control Studies; D002560:Cerebrovascular Circulation; D006801:Humans; D008875:Middle Aged; D012372:ROC Curve; D011859:Radiography; D012680:Sensitivity and Specificity; D020521:Stroke / Q000000981:diagnostic imaging / Q000503:physiopathology*