Internal trapping (IT) is a treatment option for intracranial vertebral artery dissecting aneurysms (VADAs). Medullary infarction (MI) is a complication linked to this treatment. This study aims to clarify the outcomes of IT for VADAs and the risk factors for MIs. We retrospectively reviewed the databases from 2010 to 2017 to identify patients with VADAs treated by IT at seven collaborating institutions. Radiological findings, clinical courses, and outcomes were analyzed. Perforating arteries were classified into terminal or longitudinal types using preoperative angiography. IT was completed in 90 patients (74 ruptured and 16 unruptured VADA). Postoperative rebleeding did not occur in any ruptured VADA patients. Postoperative MRI detected MIs in 26 patients (28.9%). The incidence of MIs in the ruptured VADA (32%) was higher compared with that in the unruptured VADA (13%), though it was not significant. In the MI group, the occlusion or blind alley of the terminal-type and longitudinal-type perforator was confirmed in 23 patients (88%) and 11 patients (42%), respectively. The occlusion or blind alley of the terminal-type perforator was an independent risk factor for MIs in the logistic regression analysis (OR 5.81; 95% CI 1.34–25.11; p = 0.018). In ruptured VADA, postoperative MI (OR 12.2; 95% CI 3.19–64.55; p = 0.0001) and high-grade SAH (OR 8.02; 95% CI 2.32–37.70; p = 0.0006) were independent risk factors of an unfavorable clinical outcome. In conclusion, MIs were an independent risk factor for unfavorable outcomes after IT, especially for a ruptured VADA. The occlusion or blind alley of the terminal-type perforator caused by the IT was associated with postoperative MIs.

内部诱捕 (IT) 是颅内椎动脉夹层动脉瘤 (VADA) 的一种治疗选择。延髓梗死 (MI) 是与这种治疗相关的并发症。本研究旨在阐明 IT 对 VADA 的结果和 MI 的风险因素。我们回顾性审查了 2010 年至 2017 年的数据库，以确定在七个合作机构接受 IT 治疗的 VADA 患者。分析了放射学发现、临床过程和结果。使用术前血管造影术将穿支动脉分为终末型或纵向型。90 名患者（74 名破裂的 VADA 和 16 名未破裂的 VADA）完成了 IT。任何 VADA 破裂患者均未发生术后再出血。术后 MRI 检测到 26 名患者 (28.9%) 的 MI。破裂的 VADA 中 MI 的发生率 (32%) 高于未破裂的 VADA (13%)，但并不显着。MI组终末型和纵型穿支分别有23例（88%）和11例（42%）确诊。在逻辑回归分析中，终末型穿支的闭塞或死胡同是 MI 的独立危险因素（OR 5.81；95% CI 1.34–25.11；p = 0.018）。在破裂的 VADA 中，术后 MI（OR 12.2；95% CI 3.19–64.55；p = 0.0001）和高级别 SAH（OR 8.02；95% CI 2.32–37.70；p = 0.0006）是不利临床结果的独立危险因素. 总之，MI 是 IT 后不良结果的独立危险因素，尤其是 VADA 破裂。由 IT 引起的终末型穿支的闭塞或死胡同与术后 MI 相关。