Efficacy and safety of the contralateral approach to vascular lesions in the vertebral artery: patient series.

backgroundEndovascular treatment is preferred over microsurgical clipping for intracranial aneurysms in the posterior circulation. However, access to lesions, particularly those in the regions of the vertebral artery (VA) and the posterior inferior cerebellar artery (PICA), is technically challenging in terms of the vessel diameter of the ipsilateral VA or the branching angle of the PICA. OBSERVATIONS: Nine cases of intracranial aneurysms in the region of the PICA, which were endovascularly treated with an approach beyond the vertebrobasilar junction (VBJ) from the contralateral VA in the last 4 years, are described herein. All procedures, namely stent deployment, the use of a balloon catheter, and coiling, were safely performed using the contralateral approach. Neither rebleeding nor ischemic complications occurred. All patients had favorable outcomes and no recurrence. LESSONS: All aneurysms were successfully treated using an adjunctive technique with an additional approach beyond the VBJ from the contralateral VA. The combination of both ipsilateral and contralateral approaches to VA-PICA or PICA lesions contributes to safe and effective endovascular treatment. https://thejns.org/doi/10.3171/CASE24420.