A, The soft palate, which has been preserved, is located at the level of the foramen magnum. The infratemporal fossa, located below the greater sphenoid wing and middle cranial fossa, contains the pterygoid muscles, maxillary artery, mandibular nerve branches, and the pterygoid venous plexus, and opens posteriorly into the area around the carotid sheath, as shown on the left side. B, Enlarged view. The soft palate has been divided in the midline, and the leaves reflected laterally. The atlanto-occipital joints and the foramen magnum are located at approximately the level of the hard palate. The anterior arch of C1 and the dens are located behind the oropharynx, and the clivus is located behind the nasopharynx and sphenoid sinus. The prominence over the longus capitis and the anterior arch of C1 are seen through the pharyngeal mucosa. C, The mucosa lining the posterior pharyngeal wall has been reflected to the right, exposing the longus capitis that attaches to the clivus and the part of the longus colli that attaches to the anterior arch of C1. The left eustachian tube has been divided. D, The clivus and anterior arch of C1 have been removed. The dura has been opened to expose the vertebral and basilar arteries. The dens has been preserved. The structures in the right infratemporal fossa and a segment of the right carotid artery and mandible have been removed to expose the right vertebral artery ascending between the C2 and C1 transverse processes. E, Cross section through the ethmoidal and maxillary sinuses and the nasal cavity in front of the posterior maxillary wall. The posterior wall of the maxillary sinus has been removed to expose the pterygopalatine fossa and ganglia on both sides. The maxillary nerves enter the pterygopalatine fossa by passing through the foramen rotundum. The maxillary arteries enter the pterygopalatine fossa from laterally by passing through the pterygomaxillary fissure and give rise to its terminal branches in the pterygopalatine fossa. Another branch enters the greater palatine canal with the greater palatine nerves. F, Enlarged view of the pterygopalatine fossa. The vidian nerve exits the vidian canal to enter the pterygopalatine ganglion, which receives communicating rami from the maxillary nerve. The sphenopalatine branch passes through the sphenopalatine foramen to enter the lateral nasal cavity. (Images courtesy of AL Rhoton, Jr.)