A combined retroauricular and preauricular transpetrosal-transtentorial approach to clivus meningiomas.

A combined retroauricular and preauricular transpetrosal-transtentorial approach is described for the resection of meningiomas arising from the clivus. Via radical mastoidectomy the sigmoid sinus is exposed down to the jugular bulb, and via the transmastoideal-subtemporal approach the retroauricular petrosal bone, 1 cm in depth from the petrosal ridge, and the roof of the internal auditory meatus are removed, the middle ear and fallopian canal being left intact. Additionally, via a transzygomatic-subtemporal approach the preauricular petrosal bone is removed anteriorly up to the petrosal tip and laterally as far as the petrosal portion of the internal carotid artery, while the cochlea is preserved. By this means, the triangular portion of the posterior petrosal dura mater, delimited by the superior petrosal sinus, inferior petrosal sinus, and sigmoid sinus, is well exposed extradurally. By opening the subtemporal and posterior petrosal dura mater, in combination with a tentoriotomy, adequate exposure of the basilar artery, vertebral arteries, ventral and lateral portions of the brainstem, and cranial nerves is achieved with minimal retraction of the temporal lobe and cerebellum.