How I do it? Posterior inferior cerebellar artery-intracranial vertebral artery reimplantation bypass and trapping of dissecting aneurysm involving the proximal posterior inferior cerebellar artery.

This case demonstrates the feasibility and safety of PICA-V4 reimplantation bypass, especially if the origin of the PICA is highly seated and the intracranial VA, or V4 segment, is long enough and well-exposed supra or under hypoglossal nerves.