Endovascular treatment for basilar trunk artery aneurysm in the flow diverter era: a consecutive series and review of literature

Background Endovascular treatment (EVT) for basilar artery trunk aneurysm (BTA) is inadequately studied due to its rarity. The aim of this study was to report our experience regarding treatment modalities, complications and outcomes. Methods A retrospective analysis of 2759 aneurysm patients who underwent EVT between January 2018 and December 2022 was performed. Patients with BTAs were involved, and their clinical characteristics, treatment modalities, complications, and clinical and angiographic outcomes were collected. Literatures from 2013 to 2024 were reviewed and studies included more than 5 BTA cases were summarized. Results Thirty-seven patients were involved, including 6 (16.2%) patients with ruptured BTAs. Treatment modalities included simple coiling for 5 (13.5%) patients, traditional low-metal-coverage stent for 1 (2.7%) patient, stent-assisted coiling for 20 (54.1%) patients, and flow diverter (FD) for 11 (29.7%) patients. Four (10.8%) procedure-related complications occurred, including 1 (2.7%) hemorrhage and 3 (8.1%) ischemia cases. The last angiographic follow-up (mean 9.5 ± 8.6 months) of 32(86.5%) patients showed complete occlusion in 23 (71.8%) patients, near-complete occlusion in 6 (18.8%) patients, and incomplete occlusion in 3 (9.4%) patients. Clinical follow-up (mean 33 ± 18.6 months) showed mRS 0–2 in 33 (89.2%) patients and mRS ≥ 3 in 4 (10.8%) patients, including 2 deaths. Large BTAs tended to be a risk factor for procedure-related complications( p = 0.08) and unfavorable clinical outcomes( p = 0.08). Conclusions Traditional coiling and stent-assisted coiling were still the dominant methods for BTAs, supplemented by FD for some complicated conditions such as large/giant or fusiform BTAs. Large size tends to pose additional risks for EVT.