title: Lack of correlation between pattern of collateralization and misery perfusion in patients with carotid occlusion.
abstract: OBJECTIVE
  Misery perfusion, identified by increased oxygen extraction fraction (OEF), predicts subsequent stroke in patients with carotid occlusion. The purpose of this investigation was to determine the relationship of angiographic findings to increased OEF in these patients.
  
  
  METHODS
  Forty-seven patients with carotid occlusion were studied with cerebral angiography and positron emission tomography (PET). The following angiographic data were collected blind to PET results: (1) pial collateralization, defined as retrograde filling of the MCA branches to the level of the insula; (2) presence of border zone shift; (3) presence of delayed venous phase; and (4) measurement of posterior communicating artery size. Patients were divided into 2 groups based on the PET measurement of normal or increased OEF.
  
  
  RESULTS
  Seventeen of 47 patients had increased OEF distal to the occluded carotid artery. No significant relationship between increased OEF and any angiographic finding was found. Pial collateralization was present in only 2 patients, both with increased OEF (P=0.105). Border zone shift was equally distributed between the 2 groups (12 of 30 with normal OEF and 6 of 15 with increased OEF). Delayed venous phase was present in 4 patients, 3 of whom had increased OEF (P=0.073). The relationship between the size of the posterior communicating artery and OEF was not significant by linear regression analysis (P=0.242).
  
  
  CONCLUSIONS
  With the possible but infrequent exceptions of delayed venous phase and pial collateralization, anatomic findings made on routine angiographic studies of patients with carotid occlusion do not correlate with increased OEF.
authors.affiliation: Mallinckrodt Institute of Radiology, Department of Neurology, Institute of the Jewish Hospital of St Louis, Washington University School of Medicine, St. Louis, MO, USA. derdeyn@mirlink.wustl.edu
authors.forename: C P
authors.initials: CP
authors.lastname: Derdeyn
authors.forename: A
authors.initials: A
authors.lastname: Shaibani
authors.forename: C J
authors.initials: CJ
authors.lastname: Moran
authors.forename: D T
authors.initials: DT
authors.lastname: Cross
authors.forename: R L
authors.initials: RL
authors.lastname: Grubb
authors.forename: W J
authors.initials: WJ
authors.lastname: Powers
mesh_terms: D000328:Adult; D000368:Aged; D001157:Arterial Occlusive Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002545:Brain Ischemia / Q000000981:diagnostic imaging / Q000503:physiopathology; D002340:Carotid Artery Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002533:Cerebral Angiography; D002560:Cerebrovascular Circulation; D002561:Cerebrovascular Disorders / Q000000981:diagnostic imaging / Q000503:physiopathology; D003097:Collateral Circulation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D014055:Tomography, Emission-Computed; D016896:Treatment Outcome
chemical_list: D010100:Oxygen