Petrous Apex: Approach and Tumors

The petrous apex is the bony limit at the postero-medial middle fossa floor, separating it from the posterior fossa. It is the antero-medial portion of the petrous part of the temporal bone, and it is surrounded by multiple neurovascular structures. The petrous apex area, though deep-seated, can be reached via the endoscopic transorbital approach, as demonstrated by various anatomic studies and preliminary surgical cases. Yet, its location at a confluence of remarkable neural and vascular elements demands comprehensive knowledge of the anatomy of this space from a transorbital perspective and surgical expertise. Hence, in this chapter, a concise anatomic review of the petrous apex region and a detailed description of the surgical technique will be provided, illustrated throughout anatomic pictures and explicative clinical cases.