The infratemporal fossa is an irregularly shaped cavity that is a part of the skull. It is situated below and medial to the zygomatic arch. It is not fully enclosed by bone in all directions. It contains superficial muscles, including the lower part of the temporalis muscle, the lateral pterygoid muscle, and the medial pterygoid muscle. It also contains important blood vessels such as the middle meningeal artery, the pterygoid plexus, and the retromandibular vein, and nerves such as the mandibular nerve (CN V3) and its branches.
Structure
Boundaries
The boundaries of the infratemporal fossa occur:
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anteriorly, by the infratemporal surface of the maxilla,
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posteriorly, by the tympanic part of the temporal bone,
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superiorly, by the greater wing of the sphenoid below the infratemporal crest, and by the under surface of the temporal squama, containing the foramen ovale, which transmits the mandibular branch of the trigeminal nerve, and the foramen spinosum, which transmits the middle meningeal artery.
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inferiorly, by the medial pterygoid muscle attaching to the mandible.
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medially, by the lateral pterygoid plate.
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laterally, by the ramus of mandible.
Contents
Muscles
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Lower part of the Temporalis and masseter muscle (origin of masseter muscle:lower margin of the inner surface of zygomatic bone insertion : outer surface of the ramus of the mandible)
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Lateral pterygoid muscle and medial pterygoid muscle.
Arteries
The infratemporal fossa contains the
maxillary artery (originating from the external carotid artery).
It also contains some of its branches, including the:
-
middle meningeal artery
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inferior alveolar artery
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deep temporal artery
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buccal artery
Veins
The infratemporal fossa contains the
pterygoid plexus,
and the retromandibular vein.
Nerves
The infratemporal fossa contains the
mandibular nerve, the inferior alveolar nerve, the
lingual nerve, the
buccal nerve, the chorda tympani nerve, and the
otic ganglion.
[Moore, Keith L & Dalley, Arthur (2006). Clinically oriented anatomy (5th ed.), Lippincott Williams & Wilkins.]
Mandibular nerve
The
mandibular nerve, the third branch of the
trigeminal nerve (CN V
3), also known as the "inferior maxillary nerve", enters infratemporal fossa from the middle cranial fossa through the foramen ovale of the
sphenoid bone.
The mandibular nerve gives off four nerves to the four muscles of mastication in the infratemporal fossa. These are the masseteric nerve to masseter muscle, the deep temporal nerve to temporalis muscle, the lateral pterygoid nerve to lateral pterygoid muscle, and the medial pterygoid nerve to medial pterygoid muscle. It also gives branches to mylohyoid muscle, the anterior belly of digastric muscle, the tensor veli palatini muscle, and tensor tympani muscle.
The mandibular nerve also gives off many sensory branches, including:
Communications
The infratemporal fossa is connected to other spaces in the
skull. It is connected to the middle cranial fossa by the foramen ovale and the
foramen spinosum. It is connected to the
temporal fossa, which lies deep to
zygomatic arch. It is connected to the pterygopalatine fossa through the pterygomaxillary fissure. It is connected to the orbit through the inferior orbital fissure. It is also connected to the parapharyngeal space. The inferior orbital fissure and the pterygomaxillary fissure form a T shape together.
Clinical significance
Certain
can spread into the infratemporal fossa.
This can be
Neurosurgery removed through the middle cranial fossa.
The infratemporal fossa can also be used to approach other parts of the skull.
The infratemporal fossa can be imaged using a
CT scan.
== Additional images ==
External links
