Anterior Petrosal Approach to Petrous Apex Meningioma: Climbing the Rock-Two-Dimensional Operative Video

Abstract

A 47-year-old woman was referred to the neurological surgery department after a self-limiting episode of dizziness and headache. Magnetic resonance imaging showed an extra-axial mass in the right petrous apex, suggesting a meningioma. We chose the anterior petrosal approach (APA) because meningioma is a benign tumor with brainstem compression, and our goal was total removal for potential cure of the disease. The APA is appropriate for lesions located in the superior petroclival region with a narrow dural tail, above cranial nerves VII and VIII. The posterior petrosal approach is for large petroclival meningiomas that cross the midline, involving the basilar artery and perforating branches, extending below cranial nerves VII and VIII and above the jugular foramen. The retrosigmoid approach is for lesions located in the petrous apex and petroclival regions. Limitations include working between the posterior fossa cranial nerves and removing extensions of the tumor to Meckel cave and middle fossa. The endoscopic endonasal approach is for petroclival lesions. Limitations are the longer distance, nasal disturbances, middle fossa dural tail removal, and cerebrospinal fluid fistula.^1-8 We performed the APA through a suprapetrous craniotomy, which exposes the petrous temporal portion, to drill the posteromedial triangle of the middle fossa to create a surgical corridor to the posterior fossa after splitting the tentorium.^1-8 Removal of the tumor through the APA leads to a direct route to the petrous apex, with short distance and predominant extradural dissection. We achieved gross total removal. The patient presented with transient cranial nerve IV and V disturbances, but recovered entirely in 6 weeks, returning to her professional activities with preserved quality of life (Video 1).

Keywords: Anterior petrosal; Kawase; Meningioma; Petrous apex.