Right lateral view of the middle fossa following partial removal of the petrous apex. For orientation, the bottom border of the image is superior; the top border is inferior. The trigeminal nerve emerges from the pons just lateral to the basilar artery and expands over the trigeminal depression as the trigeminal ganglion from which its three branches or divisions arise: ophthalmic (V1), maxillary (V2), and mandibular (V3). The oculomotor nerve can be seen converging on the ophthalmic nerve as they course toward the superior orbital fissure. Note the abducens nerve and its course beneath the petrosphenoidal ligament to enter the cavernous sinus coursing lateral to the internal carotid artery to the superior orbital fissure. Note also the greater superficial petrosal nerve, a branch of the facial nerve, coursing deep to the trigeminal ganglion enroute to the foramen lacerum where it joins the deep petrosal nerve. (Image courtesy of AL Rhoton, Jr.)