The infratemporal fossa, or IT fossa for short, is one of the most important spaces in the head, which acts as a conduit for neurovascular structures entering and exiting the cranial cavity. It contains vital structures such as the maxillary artery and mandibular nerve.
The infratemporal fossa is an irregularly shaped space located deep and inferior to the zygomatic arch, deep to the ramus of the mandible, and posterior to the maxilla.
More specifically, the fossa is bounded laterally by the the ramus of the mandible; medially by the lateral pterygoid plate; anteriorly by the posterior surface of the maxilla; posteriorly by the tympanic plate and the temporal bone’s mastoid and styloid processes; superiorly by the inferior surface of the greater wing of the sphenoid, and inferiorly by the attachment of the medial pterygoid muscle close to the angle of the mandible.
Now, the important structures within the infratemporal fossa include muscles, vessels and nerves.
The muscles of the infratemporal fossa include the inferior portion of the temporalis muscle, the medial pterygoid and lateral pterygoid muscles.
Lying either superficial or deep to the lateral pterygoid muscle, there’s the pterygoid venous plexus and the maxillary artery.
Deep to the lateral pterygoid, the otic ganglion and mandibular nerve or cranial nerve V3 are located inferior to the foramen ovale.
The mandibular nerve splits within the infratemporal fossa into branches that include the inferior alveolar, auriculotemporal, lingual, buccal, masseteric, and deep temporal nerves.