The Pterygopalatine Fossa, Orbit, and Maxilla. A, Enlarged anterior oblique view of the pterygopalatine fossa. The pterygopalatine ganglion receives communicating rami from the maxillary nerve. The sphenopalatine branch passes through the sphenopalatine foramen to enter the lateral nasal cavity. B, The terminal branch of the maxillary artery and nasal branches arising from the pterygopalatine ganglion penetrate the lateral wall of the nasal cavity to course along the sphenoid face. C, Anterosuperior view of the orbit. The maxillary nerve gives rise to the infraorbital, zygomatic, and superior alveolar nerves. The anterior wall of the pterygopalatine fossa is formed by the posterior wall of the maxillary sinus. D, Anterosuperior view of the maxilla. The maxillary nerve enters the infraorbital groove and canal by passing through the inferior orbital fissure and continues as the infraorbital nerve. The infraorbital nerve emerges in the face through the infraorbital foramen. E, The posterior wall of the right maxillary sinus has been removed to expose the pterygopalatine fossa. The maxillary artery is located anterior to the pterygopalatine ganglion. The palatine nerves descend through the palatine foramina of the maxilla located at the inferior tip of the pterygopalatine fossa. F, The right buccolabial muscles have been removed to expose the branches of the infraorbital nerve. The branches of the infraorbital nerve communicate with the branches of the facial nerve to form infraorbital plexus in the infraorbital space. G, The branches of the infraorbital nerve have been removed. The infraorbital nerve gives rise to anterior superior alveolar nerve just behind the infraorbital exit through the foramen. (Images courtesy of AL Rhoton, Jr.)