title: Automated CT Perfusion Ischemic Core Volume and Noncontrast CT ASPECTS (Alberta Stroke Program Early CT Score): Correlation and Clinical Outcome Prediction in Large Vessel Stroke.
abstract: The semiquantitative noncontrast CT Alberta Stroke Program Early CT Score (ASPECTS) and RAPID automated computed tomography (CT) perfusion (CTP) ischemic core volumetric measurements have been used to quantify infarct extent. We aim to determine the correlation between ASPECTS and CTP ischemic core, evaluate the variability of core volumes within ASPECTS strata, and assess the strength of their association with clinical outcomes.
  
  
  
  Review of a prospective, single-center database of consecutive thrombectomies of middle cerebral or intracranial internal carotid artery occlusions with pretreatment CTP between September 2010 and September 2015. CTP was processed with RAPID software to identify ischemic core (relative cerebral blood flow<30% of normal tissue).
  
  
  
  Three hundred and thirty-two patients fulfilled inclusion criteria. Median age was 66 years (55-75), median ASPECTS was 8 (7-9), whereas median CTP ischemic core was 11 cc (2-27). Median time from last normal to groin puncture was 5.8 hours (3.9-8.8), and 90-day modified Rankin scale score 0 to 2 was observed in 54%. The correlation between CTP ischemic core and ASPECTS was fair (R=-0.36; P<0.01). Twenty-six patients (8%) had ASPECTS <6 and CTP core ≤50 cc (37% had modified Rankin scale score 0-2, whereas 29% were deceased at 90 days). Conversely, 27 patients (8%) had CTP core >50 cc and ASPECTS ≥6 (29% had modified Rankin scale 0-2, whereas 21% were deceased at 90 days). Moderate correlations between ASPECTS and final infarct volume (R=-0.42; P<0.01) and between CTP ischemic core and final infarct volume (R=0.50; P<0.01) were observed; coefficients were not significantly influenced by the time from stroke onset to presentation. Multivariable regression indicated ASPECTS ≥6 (odds ratio 4.10; 95% confidence interval, 1.47-11.46; P=0.01) and CTP core ≤50 cc (odds ratio 3.86; 95% confidence interval, 1.22-12.15; P=0.02) independently and comparably predictive of good outcome.
  
  
  
  There is wide variability of CTP-derived core volumes within ASPECTS strata. Patient selection may be affected by the imaging selection method.
authors: From the Grady Memorial Hospital, Emory University, Atlanta, GA.
authors: Diogo C
authors: DC
authors: Haussen
authors: From the Grady Memorial Hospital, Emory University, Atlanta, GA.
authors: Seena
authors: S
authors: Dehkharghani
authors: From the Grady Memorial Hospital, Emory University, Atlanta, GA.
authors: Srikant
authors: S
authors: Rangaraju
authors: From the Grady Memorial Hospital, Emory University, Atlanta, GA.
authors: Leticia C
authors: LC
authors: Rebello
authors: From the Grady Memorial Hospital, Emory University, Atlanta, GA.
authors: Mehdi
authors: M
authors: Bouslama
authors: From the Grady Memorial Hospital, Emory University, Atlanta, GA.
authors: Jonathan A
authors: JA
authors: Grossberg
authors: From the Grady Memorial Hospital, Emory University, Atlanta, GA.
authors: Aaron
authors: A
authors: Anderson
authors: From the Grady Memorial Hospital, Emory University, Atlanta, GA.
authors: Samir
authors: S
authors: Belagaje
authors: From the Grady Memorial Hospital, Emory University, Atlanta, GA.
authors: Michael
authors: M
authors: Frankel
authors: From the Grady Memorial Hospital, Emory University, Atlanta, GA. raul.g.nogueira@emory.edu.
authors: Raul G
authors: RG
authors: Nogueira
mesh_terms: D000368:Aged; D002545:Brain Ischemia / Q000000981:diagnostic imaging*; D016208:Databases, Factual; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D055420:Perfusion Imaging / Q000379:methods*; D012189:Retrospective Studies; D020521:Stroke / Q000000981:diagnostic imaging*; D017131:Thrombectomy; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
keywords: Alberta; Fiji; follow-up; stroke; thrombectomy