Transulnar Arterial Access for Intra-Operative Cerebral Angiography during Prone Cerebrovascular Surgery

We reviewed our experience using transulnar access (TUA) to obtain intraoperative cerebral angiography during prone surgery for vascular pathology, where conventional transfemoral and transradial access can be difficult. Ten consecutive patients treated between April 2020 and August 2025 were included. Ulnar artery access was obtained in the supine position before the patient was turned prone for surgery, and angiography was performed after the procedure without repositioning. Eight patients had arteriovenous malformations and 2 had dural arteriovenous fistulas. In all cases, intraoperative angiography was successfully completed through the ulnar artery. The mean ulnar artery diameter was 2.4 mm, indicating adequate vessel size for catheterization, and mean fluoroscopy time was 7.5 minutes. No immediate access-site complications occurred, and no case required conversion to another access route. These findings suggest that TUA is technically feasible and may provide a practical option for intraoperative cerebral angiography when prone positioning limits access to traditional arterial sites. Although the study is limited by its small sample size and retrospective design, the consistent procedural success supports further investigation.