Usefulness of stent strut deformity during thrombectomy for predicting the stroke etiology in acute large artery occlusion

Abstract Background Stent retriever thrombectomy has been regarded as the standard treatment for acute intracranial large artery occlusion. As fast recanalization is the most important factor for favorable outcomes in patients with stroke, defining the etiology is important for the treatment of acute large vessel occlusion. We aimed to investigate whether full-length stent visibility during thrombectomy could provide information on the stroke etiology or the clot characteristics using the stent strut deformity during thrombectomy. Materials and methods Intra-arterial thrombectomy was performed on 46 patients with Trevo stent as the first endovascular thrombectomy device. Patients were assigned to the full expansion group or the stent deformity group based on the shape of the stent strut during the endovascular procedure. The presence of stent deformity during the procedure, underlying intracranial atherosclerotic stenosis (ICAS), and residual stenosis at the occlusion site on the final conventional angiography, follow-up magnetic resonance angiography, or computed tomography angiography were retrospectively assessed. Results Recanalization without underlying arterial stenosis at the occlusion site was observed in 92.9 % (26/28 patients) and 50.0 % (8/16 patients) of the full expansion and stent deformity groups (p = 0.002), respectively. A significantly lower proportion of patients in the full expansion group demonstrated ICAS-related occlusion compared with that in the stent deformity group (3.6 % vs. 43.8 %, respectively; p = 0.002). Conclusions The degree of stent expansion during thrombectomy in acute large artery occlusion can be a useful predictor of the stroke etiology and potentially helpful to the operator for endovascular treatment planning.