A, This approach is usually performed through a degloving incision in the buccogingival junction rather than through an incision along the margin of the nose. The upper lip and cheek flap have been reflected laterally and the anterior wall of the maxilla has been opened to expose the maxillary sinus. B, Enlarged view. The posterior wall of the maxillary sinus has been removed to expose the pterygopalatine fossa. The maxillary nerve enters the pterygopalatine fossa by passing through the foramen rotundum, where it gives rise to communicating rami to the pterygopalatine ganglion and infraorbital and palatine nerves. The terminal branches of the maxillary artery also course through the pterygopalatine fossa. C, Inferior view of another orbit after the orbital floor has been removed and the infraorbital nerve reflected posteriorly to expose the periorbita and orbital fat. D, The orbital fat has been removed to expose the medial and inferior rectus and inferior oblique muscles. The inferior oblique muscle arises from the medial orbital wall and passes laterally below the inferior rectus muscle to insert on the sclera. The branch of the inferior division of the oculomotor nerve to the inferior oblique muscle courses along the lateral side of the inferior rectus muscle. E, The inferior rectus muscle has been divided and reflected back-ward. The ophthalmic artery, in this case, courses below the optic nerve, as occurs in approximately 15% of orbits. The inferior division of the oculomotor nerve gives rise to individual branches to the medial rectus, inferior oblique, and inferior rectus muscles. A tortuous central retinal artery arises below and enters the lower margin of the optic nerve. F, The ophthalmic artery has been retracted medially to expose the origin of the parasympathetic motor root to the ciliary ganglion, which courses from the branch of the inferior oculomotor division to the inferior oblique. The ganglion gives rise to short ciliary nerves, which are distributed to the globe. (Images courtesy of AL Rhoton, Jr.)