Thrombus Attenuation Gradient Can Predict Successful First-Pass Recanalization Following Stentriever Thrombectomy

Abstract

ObjectiveComputed tomographic angiography (CTA) derived thrombus enhancement characteristics can predict the first pass (FP) recanalization. In this study, we analyzed whether dynamic contrast kinetics with in the clot in multiphase CTA can predict first pass (FP) recanalization following stentriever thrombectomy. MethodsAcute large vessel occlusive stroke evaluated with multiphasic CTA and underwent stentriever thrombectomy (MT) were selected. Thrombus perviousness on various phases like arterial, venous and delayed phases were calculated. Additionally, thrombus attenuation gradient (TAG) defined as average attenuation difference between adjacent phases were also evaluated and correlated with successful FP outcome (mTICI>2b). ResultsOf the 69 patients, 32/69 (46 %) had successful FP recanalization (group 1) and 37/69 (53%) required more than one attempts (group 2). The TAG showed significant difference in the arterial-plain and venous-arterial phases. The early increase in TAG was seen in group 1 in the arterial-plain phase compared to group 2 (12.6 vs. 9, P value - 0.01), which plateaued in the venous-arterial phase for group 1, while it showed further increment in the group 2 (2.1 vs 5.1, P value - 0.02). A cut-off value of 9.2 HU for arterial-plain phase (P value 0.001) and 4.2 HU (P value 0.001) for venous-arterial phase was predictive of FP effect. Combining two metrics had odds ratio of 2.8 for FP recanalization (P value 0.035). The accuracy evaluated in a validation cohort yielded 74%. Other features including histology were not significant. ConclusionTAG evaluated from multiphase CT can predict the first pass effect in stentriever thrombectomy.