[Surgical approach to petroclival meningioma. Value of translabyrinthine approach extended to the petrous apex].

Petro-clival meningiomas are rare tumors. Because of their deep location in the posterior fossa, many surgical approaches have been proposed, generally with severe post-operative morbidity and mortality. Thirty-six meningiomas of the petrous apex (34 posterior surface of petrous bone meningiomas, 2 clivus meningiomas) were operated, via a trans petrosal approach, from 1983 to 1993. In 14 cases, the trans-labyrinthine (TL) approach, extended by drilling the bone above the internal auditory canal (IAC) was performed (39%). In 18 cases the TL approach was extended in a subtemporal, transtentorial approach (50%). In one case (2.5%), after rerouting the facial nerve posteriorly, the TL approach was extended anteriorly in a transcochlear approach. The retro-sigmoïd approach was performed in one case (2.5%). The extended middle fossa approach was performed in two cases of clivus meningiomas (5%). Total excision was obtained in 27 cases (75%). By using the Laser, quality of resection is increased. Most complications and morbidity were encountered with tumors extending towards the cavernous sinus. Extended translabyrinthine approach allows total excision in most of cases of petro-clival meningiomas. For clivus tumors or tumors invading the cavernous sinus, the extended middle fossa approach and subtotal petrosectomy are proposed respectively.