Epi- and Subdural Anterior Petrosal Approach to Preserve Venous Flow of Sphenobasal Veins

Abstract

Objective: Anterior transpetrosal approach is well known as effective surgical procedure to the lesions at petroclival area. However, wide epidural exposure of the petrous apex might obstacle the venous flow of sphenobasal veins which might cause venous complications at the area of Sylvian veins. Recently, we developed a new technique named as epi- and subdural anterior petrosal approach to avoid venous complications and to minimize the surgical procedure. This study aims to demonstrate our technique in detail and present the effect of the procedure. Methods: Since January, 2012 our new technique is applied to 10 patients with petroclival meningioma or pontine cavernoma. The key step of our technique is limited epidural exposure of petrous bone, which can preserve venous flow around the foramen ovale. Before opening the dura mater, petrous drilling was limited just along the superior petrosal sinus (SPS) to ligate the SPS. Additional petrosectomy was performed after dural opening and cutting the SPS and tentorium. This subdural procedure can offer wider surgical corridor to petrous apex and restrict the epidural exposure of the middle fossa, which can preserve the venous flow of spehnobasal sinus and shorten the surgical time of petrosectomy. Result: All 10 pathologies were successfully removed without any venous complications. In addition, anatomical landmarks for anterior petrosectomy were easily identified in subdural procedure compared with in original epidural procedure.