The clinical effect of flow-diverting stent for treatment of unruptured internal carotid artery small- and medium-sized wide-neck aneurysms

Abstract

Objective: To study the feasibility of domestic flow diverter(TFD) for the treatment of unruptured internal carotid artery small- and medium-sized wide-neck aneurysms. Methods: This is a retrospective case series study.The study retrospectively evaluated consecutive 54 patients with unruptured intracranial small- and medium-sized wide-neck aneurysms treated with TFD in the Department of Cerebrovascular Disease,the Second Affiliated Hospital of Kunming Medical University between October 2019 and January 2024. There were 11 males and 43 females, and the age of patients was (54.9±9.6) years (range:36 to 74 years). There were 63 aneurysms in 54 patients,6 of which were tandem multiple small aneurysms. One case had saccular aneurysms of bilateral internal carotid artery. The maximum diameter of aneurysm was (4.1±0.8) mm (range: 1.5 to 10.0 mm).The ratio of the maximum diameter of the aneurysm to the neck width diameter was 1.3±0.4 (range:0.4 to 2.4). The surgical and follow-up data were collected. The aneurysm embolization rate at the immediate operation and follow-up,and the complications were analyzed. The degree of aneurysm embolization was evaluated using the O'Kelly-Marotta (OKM) grading system,with OKM grade D as complete occlusion and grade C and above (C1,C2,C3 and D) as successful occlusion. Clinical outcomes of all patients were evaluated by modified Rankin scale(mRS). Results: For 63 aneurysms, 48 aneurysms were treated with TFD alone,and 15 aneurysms were treated with a combination of TFD and coiling. The immediate postoperative successful occlusion rate was 14.3% (9/63) and the complete occlusion rate was 3.2% (2/63). Follow-up results were obtained for all of the patients. The follow-up time (M(IQR)) was 124 (182) days (range: 85 to 754 days). The time to aneurysm successful occlusion was 140.5 (151.5) days (range: 85 to 308 days). At final follow-up,the successful aneurysm occlusion rate was 68.3% (43/63) and the complete occlusion rate was 58.7% (37/63). The complete occlusion rate of the TFD group was 50.0% (24/48) and the TFD+coiling group was 13/15. All patients had no aneurysm rupture,ischemic complications and no recurrence of the aneurysm needed to retreatment during the intraoperative and follow-up period. A total of 3 mild haemorrhagic complications which were related to dual-antiplatelet agents. Twelve patients had asymptomatic mild-moderate stent stenosis. TFD covered 66 branch vessels totally. Only 6 branches were affected by the time of the last follow-up and none of the patients had relevant ischaemic symptoms. All of 54 patients were evaluated as mRS score<2 points at the last follow-up. Conclusion: Using TFD to treat internal carotid artery unruptured small and medium-sized wide-neck aneurysms can simplify the surgical procedure with low complication rate, which is a clinically optional treatment approach.