[Transpetrosal approaches to the clivus. Surgical anatomy, challenges and limitations].

Radical excision of skull base tumors is a real challenge for neurosurgeons. The need to preserve the nerves and the vessels in the area lead us to use lateral approaches, if the lesion lies lateral to the cavernous portion of the carotid artery and behind the petrous apex. Lateral approaches are classified into two groups: ventrolateral approaches (in front of the cochlea) and dorsolateral approaches (with or without resection of the bony labyrinth). The three surgical approaches studied were the subtemporal preauricular infratemporal, the subtemporal anterior transpetrosal, and the combined supra and infratentorial presigmoid approach. The approaches were performed on adult cadaver heads fixed in formolin. The technique, the exposure, the modifications and extensions, as well as the problems of reconstruction are discussed.