A male in his 30s was found down after presumed trauma. CT head demonstrated diffuse
SAH + IVH (mFG 4, Hunt–Hess 4). Angiogram demonstrated a proximal left PICA dissecting
fusiform aneurysm. Decision was made to surgically treat via a left extended far lateral
craniotomy with OA-PICA bypass and clipping. The OA graft was harvested in an inside-out
technique and anastomosed on the caudal loop of PICA followed by clip ligation of
the proximal left PICA.
