title: Low Cerebral Blood Volume Identifies Poor Outcome in Stent Retriever Thrombectomy.
abstract: BACKGROUND
  Mechanical thrombectomy (MT) is an efficient treatment of acute stroke caused by large-vessel occlusion. We evaluated the factors predicting poor clinical outcome (3-month modified Rankin Scale, mRS >2) although MT performed with modern stent retrievers.
  
  
  METHODS
  We prospectively collected the clinical and imaging data of 105 consecutive anterior circulation stroke patients who underwent MT after multimodal CT imaging. Patients with occlusion of the internal carotid artery and/or middle cerebral artery up to the M2 segment were included. We recorded baseline clinical, procedural and imaging variables, technical outcome, 24-h imaging outcome and the clinical outcome. Differences between the groups were studied with appropriate statistical tests and binary logistic regression analysis.
  
  
  RESULTS
  Low cerebral blood volume Alberta stroke program early CT score (CBV-ASPECTS) was associated with poor clinical outcome (median 7 vs. 9, p = 0.01). Lower collateral score (CS) significantly predicted poor outcome in regression modelling with CS = 0 increasing the odds of poor outcome 4.4-fold compared to CS = 3 (95% CI 1.27-15.5, p = 0.02). Lower CBV-ASPECTS significantly predicted poor clinical outcome among those with moderate or severe stroke (OR 0.82, 95% CI 0.68-1, p = 0.05) or poor collateral circulation (CS 0-1, OR 0.66, 95% CI 0.48-0.90, p = 0.009) but not among those with mild strokes or good collaterals.
  
  
  CONCLUSIONS
  CBV-ASPECTS estimating infarct core is a significant predictor of poor clinical outcome among anterior circulation stroke patients treated with MT, especially in the setting of poor collateral circulation and/or moderate or severe stroke.
authors.affiliation: Medical Imaging Center, Tampere University Hospital, PL2000, 33521, Tampere, Finland. sara.protto@pshp.fi.
authors.forename: Sara
authors.identifier: http://orcid.org/0000-0003-2131-7739
authors.initials: S
authors.lastname: Protto
authors.affiliation: Medical Imaging Center, Tampere University Hospital, PL2000, 33521, Tampere, Finland.
authors.forename: Juha-Pekka
authors.initials: JP
authors.lastname: Pienimäki
authors.affiliation: Medical Imaging Center, Tampere University Hospital, PL2000, 33521, Tampere, Finland.
authors.forename: Janne
authors.initials: J
authors.lastname: Seppänen
authors.affiliation: Department of Neurology, Tampere University Hospital, Tampere, Finland.
authors.forename: Heikki
authors.initials: H
authors.lastname: Numminen
authors.affiliation: Medical Imaging Center, Tampere University Hospital, PL2000, 33521, Tampere, Finland.
authors.forename: Niko
authors.initials: N
authors.lastname: Sillanpää
mesh_terms: D000208:Acute Disease; D000368:Aged; D000818:Animals; D002533:Cerebral Angiography / Q000379:methods; D002536:Cerebral Arteries / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery*; D000071937:Cerebral Blood Volume / Q000502:physiology*; D004285:Dogs; D005260:Female; D006801:Humans; D008297:Male; D011446:Prospective Studies; D015607:Stents; D020521:Stroke / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D017131:Thrombectomy / Q000379:methods*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
keywords: Interventional radiology; Ischemic stroke; Mechanical thrombectomy; Perfusion CT