Effect analysis of Solitaire stent retriever thrombectomy in anterior circulation occlusion involving various locations

Objective To evaluate the technical success and clinical functional outcomes of mechanical thrombectomy (MT) by Solitaire stent in anterior circulation occlusion involving varying locations. Methods We retrospectively reviewed 148 patients with anterior circulation occlusion who were admitted to Department of Neurosurgery, 101st Hospital of PLA and underwent MT from March 2015 to September 2017. According to locations, all patients were divided into internal carotid artery (ICA) group (n=42), middle cerebral artery (MCA) M1 group (n=70) and M2 group (n=36). Revascularization was evaluated with modified thrombolysis in cerebral infarction (mTICI). Clinical outcomes were assessed based on National Institutes of Health stroke scale (NIHSS) and modified Rankin scale (mRS). Baseline clinical and imaging variables, time from onset to recanalization, duration of the procedure, revascularization, perioperative complications and mRS at 90 d post stroke were documented. Results The results of mTICI 2b or 3 was achieved in 96 (64.9%) cases and there were no significant differences among the 3 groups [66.7%(28/42), 71.4%(50/70), 50.0%(18/36), P=0.091]. Overall, 76 out of 148 (51.4%) patients experienced favorable clinical outcome (mRS of 0-2) with no significant difference among the 3 groups [42.9%(18/42), 58.6%(41/70), 47.2%(17/36), P=0.231]. In ICA and M1 groups, favorable clinical outcome was more often seen in patients who achieved successful recanalization (ICA: 57.1% vs. 14.3%, P=0.009; M1: 70.0% vs. 30.0%, P=0.003). In patients with M2 occlusions, favorable clinical outcome was reported in 55.6% (10/18) of cases with successful recanalization and 38.9% (7/18) of those with unsuccessful recanalization, which had no significant difference (P=0.514). Conclusions There seems to be no statistically significant difference in the recanalization or clinical outcomes among ICA, M1 and M2 cases that underwent treatment with Solitaire stent. The beneficial effect of endovascular reperfusion using Solitaire stent might more pronounced for patients with ICA and M1 occlusions than for patients with M2 occlusions. Key words: Stroke; Brain ischemia; Treatment outcome; Mechanical thrombectomy; Solitaire stent