infratemporalfossan

The infratemporal fossa is an irregular, cone-shaped space of the skull base located inferior to the temporomandibular joint and deep to the ramus of the mandible. It lies on the sphenoid and maxillary bones and communicates with the middle cranial fossa via the foramen ovale and foramen spinosum, with the pterygopalatine fossa through the pterygomaxillary fissure, and it opens inferiorly toward the neck.

Boundaries are defined by the greater wing of the sphenoid above; the posterior surface of the maxilla anteriorly; the lateral pterygoid plate medially; the ramus of the mandible laterally; and the tympanic plate and mastoid part of the temporal bone posteriorly. The inferior aspect blends with adjacent spaces in the lower face and neck.

Contents of the infratemporal fossa include the muscles of mastication, notably the lateral and medial pterygoids; branches of the mandibular division of the trigeminal nerve (V3), including the inferior alveolar nerve, lingual nerve, buccal nerve, and auriculotemporal nerve; the otic ganglion; nerves to the tensor tympani and tensor veli palatini; and hitchhiking fibers from the chorda tympani. The maxillary artery and its branches traverse the fossa, accompanied by the pterygoid venous plexus. Lymphatics are present, and veins and autonomic ganglia are closely associated with the neural elements.

Clinical relevance centers on anesthesia and surgery in this region (for example, inferior alveolar nerve block), as well as the risk of vascular injury or infection spreading via the pterygoid venous plexus to adjacent spaces.