Thrombus Enhancement Sign May Differentiate Embolism From Arteriosclerosis-Related Large Vessel Occlusion

Background and Purpose To evaluate whether the thrombus enhancement sign (TES) can be used to differentiate embolic large vessel occlusion (LVO) from in situ intracranial atherosclerotic stenosis (ICAS)-related LVO in the anterior circulation of patients with acute ischemic stroke (AIS). Methods Patients with LVO in the anterior circulation who underwent both non-contrast computed tomography (CT) and CT angiography and mechanical thrombectomy were retrospectively enrolled. Both embolic LVO (embo-LVO) and in situ ICAS-related LVO (ICAS-LVO) were confirmed by two neurointerventional radiologists after reviewing the medical and imaging data. TES was assessed to predict embo-LVO or ICAS-LVO. The associations between occlusion type and TES, along with clinical and interventional parameters, were investigated using logistic regression analysis and a receiver operating characteristic curve. Results A total of 288 patients with AIS were included and divided into an embo-LVO group (n=235) and an ICAS-LVO group (n=53). TES was identified in 205 (71.2%) patients and was more frequently observed in those with embo-LVO, with a sensitivity of 83.8%, specificity of 84.9%, and area under the curve (AUC) of 0.844. Multivariate analysis showed that TES (odds ratio [OR], 22.2; 95% confidence interval [CI], 9.4-53.8; P<0.001) and atrial fibrillation (OR, 6.6; 95% CI, 2.8-15.8; P<0.001) were independent predictors of embolic occlusion. A predictive model that included both TES and atrial fibrillation yielded a higher diagnostic ability for embo-LVO, with an AUC of 0.899. Conclusion TES is an imaging marker with high predictive value for identifying embo-and ICAS-LVO in AIS and provides guidance for endovascular reperfusion therapy.