Surgical management of large posterior petrous meningiomas through extended retrosigmoid approach

Abstract

Objective To evaluate extended retrosigmoid approach for surgery on large posterior petrous meningiomas. Methods During 5 - year period between 2004 and 2009, sixteen patients with large posterior petrous meningiomas were treateded through extended retrosigmoid approach. The maximum diameters of tumors were all more than 4 cm. The petrous bone erosion by lesions was found in 4 cases. The sigmoid sinus and the transverse sinus were thoroughly exposed after bone removal including mastoid and occipital bones. The sigmoid sinus was pulled anteriorly and the transverse sinus upward in order to widen the opening into the infratentorial space and the posterior surface of the petrous bone. Results Gross total resection of the tumors were achieved in 15 cases, subtotal resection in 1 case. There was no perioperative death. The symptoms disappeared or improved after surgery in 15 patients. There was a patient with irreversible hemifacial palsy. Cerebrospinal fluid rhinorrhea was found in one case. There was no tumor recurrence in all cases confirmed by MRI scanning during the follow - up period ( 3 to 60 months).Conclusion The extended retrosigmoid approach provides early devascularization of the tumor from its dural attachment to petrous pyramid, enhances surgical exposure and increases the complete tumor resection rate. Key words: Meningioma; Microsurgery; Skull base; Operative approach