SURG-29. APPROACH SELECTION FOR COMPLEX, MULTI-COMPARTMENTAL PETROCLIVAL MENINGIOMAS: A SYSTEMATIC REVIEW OF ENDOSCOPIC AND TRANSCRANIAL APPROACHES TO AN EXCEEDINGLY DIFFICULT CLASS OF SKULL BASE LESIONS

Abstract

Abstract INTRODUCTION Petroclival meningiomas are among the most formidable and technically challenging tumors in skull base surgery owing to their deep-seated location and proximity to critical neurovascular structures. Herein, we seek to understand why skull base surgeons preoperatively plan the staged excision of petroclival meningiomas. METHODS Three databases were queried per PRISMA to identify studies describing the indications for staging surgical resection of petroclival meningiomas. RESULTS Fourteen studies describing 187 patients (59.3% female, age range: 5 – 81 years) met inclusion criteria. The most common presenting symptom at diagnosis was headache (24.6%). Other common symptoms included cerebellar signs (16.0%) and gait disturbances (13.4%). Petroclival meningiomas were most commonly observed extending to the cavernous sinus (52.88%) and meckel’s cave (49.04%). With respect to critical neurovasculature, the trigeminal nerve was involved in a majority (54.59%) of petroclival meningiomas, while other relevant cranial nerves with tumor involvement included the facial (16.22%) and vestibulococcular (12.43%). Additionally, the most commonly involve vascular structures were the basilar (2.16%) superior cerebellar arteries (1.62%). Of the 187 patients who underwent surgical resection of petroclival meningioma, 144 (77%) underwent surgery involving a single stage, while 43 (23%) underwent surgery in which a two-stage approach was used. The most common single-stage approaches were the retrosigmoid (n = 35) and transpetrosal (n = 22), while the most common approaches employed in a multi-stage fashion were the subtemporal (n = 6), pterional (n = 5), and suboccipital (n = 4) approaches. To clarify, these approaches were each performed as one half of a two-stage surgery involving a second, separate approach. CONCLUSION Common approaches used in multi-stage procedures included the retrosigmoid, anterior petrosectomy, posterior petrosectomy, orbitozygomatic, translabrynthine, and various combinations thereof. Indications for performing surgery in this manner include coexistence of lesion in both middle and posterior skull base compartments, absence of meaningful hearing function, tumor size, and surgeon preference.