1992 Volume 1 Issue 1 Pages 70-74
A rare case is reported of a distal posterior inferior cerebellar artery (PICA) aneurysm associated with a megadolichobasilar anomaly. This 71-year-old woman was deeply comatose on admission and a thick and diffuse subarachnoid hemorrhage was disclosed in a CT scan. A right vertebral angiography revealed a megadolichobasilar anomaly and an aneurysm located at the junction of the posterior medullary and the supratonsillar segments (the choroidal point) of the left PICA. She underwent a successful neck clipping of the aneurysm 16 days later. Over the next one and half months her level of consciousness gradually improved so that she was able to open and close her eyes and to grasp and release hands to a verbal command. Mild left oculomotor palsy, which was regarded as a pathognomonic sign suggesting a megadolichobasilar anomaly was presented. Unfortunately she suffered from respiratory failure and died on the 73rd postoperative day. Incidence of the megadolichobasilar anomaly was reported approximately 1.5% in autopsy. Correlation between the megadolichobasilar anomaly and this rare aneurysm, constituting less than 0.5% of all intracranial aneurysms, is discussed.
