Extracranial aneurysms of the distal posterior inferior cerebellar artery: Resection and primary reanastomosis as the preferred management approach
This is a 70-year-old female who was found unresponsive, and was brought to an outside hospital where head CT showed SAH in the basal, peripontine, and foramen magnum cisterns, as well as intraventricular hemorrhage (IVH) in the occipital horns, third and fourth ventricles. The patient arrived as Hunt and Hess grade III SAH. A repeat CT demonstrated moderate enlargement of the ventricular system correlating with hydrocephalus and a right frontal EVD was placed. A four vessel cerebral angiogram showed an approximately 9 × 9 mm left PICA aneurysm located at the level of the caudal loop (tonsillomedullary segment). The aneurysm was single lobed, fist shape in appearance, angiographically located at the skull base, likely at the level of the VA dural penetration, with what appeared to be both intracranial and extracranial components [ and ]. Subselective angiography demonstrated separate inflow and outflow branch vessels []. Coil embolization was attempted but the procedure was aborted as it was felt that there was high risk of a left PICA occlusion and subsequent ischemic infarct.