Foramen lacerum *** The foramen lacerum is on the base of the skull. The pterygopalatine fossa is a small triangular space behind and below the orbital cavity. It communicates laterally with the infratemporal fossa through the pterygomaxillary fissure, medially with the nasal cavity through the sphenopalatine foramen, superiorly with the skull through the foramen rotundum, and anteriorly with the orbit through the inferior orbital fissure. The pterygopalatine ganglion lies in the pterygopalatine fossa just below the maxillary nerve (V-2). The pterygopalatine ganglion receives preganglionic parasympathetic fibers from the facial nerve by way of the greater petrosal nerve. The pterygopalatine ganglion sends postganglionic parasympathetic fibers to the lacrimal gland and glands in the palate and the nose. Note: The maxillary nerve (V-2) and the pterygopalatine portion of the maxillary artery pass through the pterygopalatine fossa. Bony Opening Location (Bone) Contents Sphenopalatine foramen Sphenoid and palatine Sphenopalatine artery and vein, nasopalatine nerve Pterygoid canal Sphenoid Deep and greater petrosal nerves that form nerve of pterygoid canal, area vessels Pterygomaxillary Sphenoid and maxilla Posterior superior alveolar vein, artery and nerve, fissure maxillary artery Foramen rotundum Sphenoid Maxillary nerve (V2) Inferior orbital fissure Sphenoid and maxilla Infraorbital and zygomatic nerves, infraorbital artery, and ophthalmic vein Pterygopalatine canal Maxilla and palatine Greater and lesser palatine veins, arteries and nerves Pharyngeal canal Sphenoid and palatine Pharyngeal branch of V-2