COMBINED TRANSSYLVIAN-SUBTEMPORAL EXPOSURE OF CEREBRAL ANEURYSMS INVOLVING THE BASILAR APEX

The surgical repair of cerebral aneurysms involving the apex of the ba silar artery continues to undergo refinement and evolution. The inhere nt difficulty in accessing the basilar apex as well as the complexitie s of the microanatomy render this area a notoriously hazardous and tec hnically challenging region in which to perform microsurgical clipping of cerebral aneurysms. Several operative approaches have been describ ed and are constantly undergoing a state of evolution in the hopes of optimizing the exposure of the distal basilar artery and minimizing th e inherent risks of surgery. The consistent decline in operative morbi dity has paralleled improved understanding of the microvascular anatom y, both in this region and along the various corridors of approach. No single operative approach is universally superior, considering the wi de variability of individual patient anatomy and vascular configuratio ns. Each approach has strengths, weaknesses, and potential complicatio ns that must be considered in the thought process of planning an opera tive attack on a basilar apex aneurysm. Intimate familiarity with the microvasculature and the microsurgical anatomy of the region is an imp erative prerequisite for the application of any surgical approach to t his region. This paper outlines a detailed review of the microsurgical anatomy that is pertinent to microsurgery of aneurysms in this region , and describes an approach referred to as the combined transsylvian-s ubtemporal approach. We have found this operative approach particularl y useful in aneurysm surgery of the basilar apex but do not mean to im ply that this single approach is suitable for all surgeons or all pati ents. This paper is designed to discuss an approach and microanatomic understanding that we find useful in the surgical treatment of aneurys ms involving the basilar apex.