Extended retrosigmoid approach for surgery of large petroclival meningiomas

Abstract

Objective To evaluate the extended retrosigmoid approach for surgery of large petroclival meningiomas. Methods We retrospectively analyzed our experience in 6 patients with large petroclival meningiomas treated by extended retrosigmoid approach. The maximum diameter of tumors ranged from 3.4 to 6. 7 cm （ mean, 4. 5 cm）. The sigmoid sinus and the transverse sinus were thoroughly exposed with the bone removal including mastoid and occipital bones. The stay sutures of the dura flaps were performed to pull the sigmoid sinus anteriorly and the transverse sinus upward to widen the opening into the infratentorial space and the posterior surface of the petrous bone. Results Gross total resection of the tumors was achieved in 3 cases, subtotal resection in 2 cases and partial resection in 1 case. No patients died. The neurological deficits improvement was found in 1 case, unchanged in 3 cases, and 2 patients were found to have new cranial nerves palsy. There was no CSF leakage and infections after operations. There was no tumor recurrence or growth by MRI scanning during the follow-up period of 6 to 58 months in all patients. Conclusion The extended retrosigmoid approach can enhance the surgical exposure, enlarge the operative view, cut the blood supply of tumor earlier, and avoid the excessive retraction on cerebellum, as well as facilitate the protection of these vital cranial nerves and vessels around brain stem. Key words: Meningioma ; Microsurgery ; Skull base ; Operative approach