A Combined Arterial and Venous Grading Scale to Predict Outcome in Anterior Circulation Ischemic Stroke

Abstract

Objective: Prognostic evaluation based on cortical vein score difference in stroke (PRECISE) score, a novel venous grading scale better predicted stroke outcomes. Henceforth, we aimed to describe and determine if a physiologically relevant combined arterial and venous grading scale (CRISP grading scale) is accurate in determining 90-day stroke outcomes in patients with proximal arterial occlusion in the anterior circulation.

Methods: Data are from the Keimyung Stroke Registry. Consecutive patients with M1 middle cerebral artery (MCA) or terminal internal carotid artery (ICA) occlusion on CT-angiography (CTA) from May-2004 to July-2008 were included. The affected hemisphere 'four veins composite score' and 'arterial collaterals' were each graded 'good' and 'poor'. On the combined scale, a 'good' grade represented a 'good' score on both scales and a 'poor' grade represented a 'poor' score on both scales. The 'other two' combinations were graded 'intermediate.'

Results: Eighty-one patients were included in the study. Dummy variable regression analysis demonstrated that poor outcome was commonly seen in the group with poor arterial and venous grades [OR(95%CI); 48 (8.24, 279.598); P < 0.00001] as opposed to poor arterial collaterals alone [OR(95%CI); 9.6(1.483,62.162); P = 0.018]. In multivariate analysis the CRISP grade [OR(95%CI); 2.638(1.192, 6.039), P = 0.017] and National Institutes of Health Stroke Scale [OR(95%CI);1.230(1.085, 1.395),P = 0.001(per unit increase)] emerged as the independent predictors of poor outcome (modified Rankin Scale >2) when adjusted for other imaging predictors of outcome.

Conclusion: CRISP grading was precise in predicting stroke outcomes when compared to individual imaging scales including arterial collateral grading, PRECISE score and CTA-SI ASPECTS in patients with proximal arterial occlusion in the anterior circulation.

Keywords: CT angiography; Cerebral veins; acute ischemic stroke; cerebral perfusion; collaterals; imaging; prognosis.