Pyramidal Approach with Partial Petrosectomy in Management of Petrous Apex Meningiomas and Other Petroclival Tumors

Introduction: One of the varieties of posterolateral approaches to the petrous apex is the pyramidal approach. It is a combination of subtemporal and retrosigmoid accesses with partial petrosectomy, which is limited by facial nerve canal and labyrinth. The most frequent neoplasm in the region of the petrous apex is meningioma. In its slow growth it can penetrate the clival region, cerebellopontine angle, middle cranial fossa, and even invade cavernous sinus. In its advanced stages it becomes an interdisciplinary problem, requiring the cooperation of the neurosurgeon, ENT, and facial surgeon. Material and Methods: Since 1999 we performed 13 such procedures. There were 10 petroclival meningiomas, 1 epidermal cyst, 1 chondromyxoma, and 1 hemangiopericytoma in our group. During operation continuous monitoring of AEP, SEP, and 3rd, 5th, 6th, and 7th cranial nerves was performed. We present a detailed analysis of the neurological state in short and long postoperative periods. Results: Total resection of the tumor was achieved in 9 cases, subtotal in 3 cases, and in 1 case partial removal was performed. There was no immediate postoperative mortality, but 1 patient died on the 10th day after operation due to pulmonary embolism. In 2 cases severe complications appeared: one was brainstem ischemia with deep hemiparesis, the second was postoperative hematoma in the left temporal lobe due to vein of Labbé damage, with consecutive ischemia of the temporal and occipital lobes. Conclusions: The authors present immediate and late results of operations, discussing benefits and limitations of this approach. As the most important and requiring special attention during this procedure, we consider: exposure of transverse and sigmoid sinus; superior petrosal sinus ligation and transection with special care of the vein of Labbé; tentorium transection; cranial nerve and blood vessel identification and preparation; entrance into cavernous sinus region; dura closure; and reconstruction of pyramid. Preoperative embolization of feeding arteries is very helpful.