View of the left middle ear after petrosectomy. Deep to the tympanic membrane, the middle ear consists of the stapes, the incus and the malleus bones. The chorda tympani arises from the postgeniculate facial nerve and courses in a recurrent fashion within the petrous bone directly over the tympanic membrane and middle ear complex. The incus is connected to the mastoid bone via the incus posterior ligament and, in combination with the ligaments of the malleus, forms the axis around which the ossicles rotate. The posterior semicircular canal lies just inferior to the geniculate ganglion. The cochlear nerve, along with the superior and inferior vestibular nerves, have been transected. The anterior inferior cerebellar artery loops near the internal acoustic meatus, and the cranial nerves IX-X-XI complex can be seen just inferior prior to exiting the skull via the jugular foramen. (Image courtesy of AL Rhoton, Jr.)