Left maxillotomy and related anatomy. Extensive bony removal of the lateral skull in this specimen reveals the contents of the lateral orbit, including the eyeball, lacrimal gland, and the lateral and inferior rectus and inferior oblique muscles. These latter two muscles are supplied by branches of the oculomotor nerve. Posterior and inferior to the orbit is the floor of the middle fossa. Here, on the apex of the petrous temporal bone is the trigeminal ganglion from which arise the ophthalmic, maxillary, and mandibular divisions. The ophthalmic nerve enters the orbit through the superior orbital fissure. The maxillary nerve enters the pterygopalatine fossa through the foramen rotundum, and the mandibular nerve descends through foramen ovale to the infratemporal fossa. Vidian nerve also enters the pterygopalatine fossa via the pterygoid canal. The greater and lesser palatine branches of the maxillary nerve gain the hard and soft palate, respectively, via the greater palatine canal. The lingual branch of the mandibular nerve is sensory to the floor of the mouth and anterior two-thirds of the tongue and unites with the chorda tympani nerve, a branch of the facial nerve, to convey taste fibers to the anterior tongue and preganglionic parasympathetic fibers to the submandibular ganglion for secretomotor innervation of the submandibular and sublingual glands. The inferior alveolar nerve supplies sensory innervation to the mandibular teeth and lower lip and chin and the roots of the auriculotemporal nerve enclose the middle meningeal artery. This artery is a branch of the maxillary and enters the middle fossa via the foramen spinosum to supply most of the meninges and overlying skull bone. (Image courtesy of AL Rhoton, Jr.)