The microsurgical anatomy that provides the basis for dealing with les
ions arising in the petroclival region was reviewed in 15 adult cadave
r heads and 25 dry skulls. The eight surgical approaches studied were
the retrosigmoid, extreme lateral transcondylar, translabyrinthine, tr
anscochlear, combined supra and infratentorial presigmoid, subtemporal
anterior transpetrosal, subtemporal preauricular infratemporal, and t
he postauricular transtemporal approach. Considerations important in t
he selection of these approaches are discussed. Special attention was
directed to the course of the facial nerve and internal carotid artery
in the temporal bone and the major venous pathways draining the regio
n.