title: CT angiography clot burden score and collateral score: correlation with clinical and radiologic outcomes in acute middle cerebral artery infarct.
abstract: OBJECTIVE
  Clot extent, location, and collateral integrity are important determinants of outcome in acute stroke. We hypothesized that a novel clot burden score (CBS) and collateral score (CS) are important determinants of clinical and radiologic outcomes and serve as useful additional stroke outcome predictors.
  
  
  METHODS
  One hundred twenty-one patients with anterior circulation infarct presenting within 3 hours of stroke onset were reviewed. The Spearman correlation was performed to assess the correlation between CBS and CS and clinical and radiologic outcome measures. Patients were dichotomized by using a 90-day modified Rankin scale (mRS) score. Uni- and multivariate logistic regression models were used to assess variables predicting favorable clinical and radiologic outcomes. Receiver operating characteristic and intraclass correlation coefficient (ICC) analyses were performed. Diagnostic performance of a CBS threshold of >6 was assessed.
  
  
  RESULTS
  There were 85 patients (mean age, 70 +/- 14.5 years). Patients with higher CBS and CS demonstrated smaller pretreatment perfusion defects and final infarct volume and better clinical outcome (all, P < .01). CBS (P = .009) and recanalization (P = .015) independently predicted favorable outcome. A CBS >6 predicted good clinical outcome with an area under the curve of 0.75 (95% confidence interval [CI], 0.65-0.84; P = .0001), sensitivity of 73.0 (95% CI, 55.9-86.2), and specificity of 64.6 (95% CI, 49.5-77.8). The recanalization rate with intravenous recombinant tissue plasminogen activator was higher in patients with CBS >6 (P = .04; odds ratio, 3.2; 95% CI, 1.1-9.4). The ICC was 0.97 (95% CI, 0.95-0.98) and 0.87 (95% CI, 0.80-0.91) for CBS and CS, respectively.
  
  
  CONCLUSIONS
  CBS and CS are useful additional markers predicting clinical and radiologic outcomes.
authors.affiliation: Department of Neuroradiology, Sunnybrook Health Science Centre, Toronto, Ontario, Canada.
authors.forename: I Y L
authors.initials: IY
authors.lastname: Tan
authors.forename: A M
authors.initials: AM
authors.lastname: Demchuk
authors.forename: J
authors.initials: J
authors.lastname: Hopyan
authors.forename: L
authors.initials: L
authors.lastname: Zhang
authors.forename: D
authors.initials: D
authors.lastname: Gladstone
authors.forename: K
authors.initials: K
authors.lastname: Wong
authors.forename: M
authors.initials: M
authors.lastname: Martin
authors.forename: S P
authors.initials: SP
authors.lastname: Symons
authors.forename: A J
authors.initials: AJ
authors.lastname: Fox
authors.forename: R I
authors.initials: RI
authors.lastname: Aviv
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002533:Cerebral Angiography / Q000379:methods*; D002548:Cerebral Revascularization; D002560:Cerebrovascular Circulation; D003097:Collateral Circulation; D005260:Female; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000000981:diagnostic imaging* / Q000628:therapy; D020767:Intracranial Thrombosis / Q000000981:diagnostic imaging* / Q000628:therapy; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome