Thrombus iodine-based perviousness is associated with recanalisation and functional outcomes in endovascular thrombectomy

Background Dual-energy CT (DECT) provides several novel methods to assess thrombus perviousness. We aimed to evaluate whether the novel thrombus perviousness measured with DECT is associated with improved recanalisation and better functional outcomes in acute ischaemic stroke (AIS) patients with endovascular thrombectomy (EVT). Methods 108 AIS patients with middle cerebral artery occlusion who underwent DECT angiography on admission and received EVT treatment between April 2020 and September 2023 were retrospectively analysed. Thrombus attenuation increase (TAI) was evaluated on routine CT angiography and non-contrast CT, and DECT quantitative parameters of thrombus, including iodine concentration (IC) and normalised IC (NIC) were measured. Multivariable logistic regression analysis was used to evaluate the association of thrombus characteristics with arterial occlusive lesion scale and 90-day modified Rankin Scale. Results NIC was significantly associated with successful recanalisation (OR 1.372 (95% CI 1.194 to 1.625); p<0.001) and good functional outcome (OR 1.252 (95% CI 1.114 to 1.446); p<0.001). NIC yielded higher performance, with area under curve (AUC) of 0.789 and 0.740, in the prediction of recanalisation and functional outcome than TAI (AUCs=0.635 and 0.592). Compared with low-level NIC thrombus, high-level NIC was associated with 11.4 and 15.4 times higher likelihood of successful recanalisation and good functional outcome. Moreover, NIC was a significant indicator to differentiate large artery atherosclerosis from cardioembolism stroke with high specificity and positive predictive value. Conclusions Higher DECT-derived NIC is associated with increased odds of successful recanalisation and good functional outcome for EVT patients, and it yielded higher prediction performance than TAI.