Infratemporal fossa Flashcards
what is the infratemporal fossa?
a complex and irregularly shaped space (wedge shape), located deep to the masseter muscle
function of infratemporal fossa?
The infratemporal fossa acts as a pathway for neurovascular structures passing between the cranial cavity, pterygopalatine fossa and temporal fossa
where is the infratemporal fossa located?
It is located deep to the masseter muscle and zygomatic arch (to which the masseter attaches)
what is the infratemporal fossa connected to? by?
the pterygopalatine fossa by the pterygomaxillary fissure and also communicates with the temporal fossa superiorly
what forms the boundaries of the infratemporal fossa?
bone and soft tissue
lateral border of infratemporal fossa?
ramus of the mandible
medial border of infratemporal fossa?
lateral pterygoid plate of the sphenoid
anterior border of infratemporal fossa?
posterior surface of the maxilla
posterior border of infratemporal fossa?
carotid sheath
floor of the infratemporal fossa?
medial pterygoid muscle
roof of infratemporal fossa?
the greater wing of the sphenoid bone
what opens out onto the roof of the infratemporal fossa?
Two foramina open out on the roof:
foramen ovale
foramen spinosum
function of foramen ovale and foramen spinosum on the roof of infratemporal fossa?
They provide a connection with the cranial cavity
how do you figure out where the infratemporal fossa is?
clench jaw and feel for masseter muscle in cheek (this is above the fossa)
contents of the infratemporal fossa?
3 muscles (of mastication)
1 artery
1 venous plexus
nerves
what are the muscles within the infratemporal fossa?
superior + inferior heads lateral pterygoid muscles (within fossa)
superficial + deep heads of medial pterygoid (within fossa)
inferior temporalis muscle
artery of the infratemporal fossa?
The maxillary artery travels through the infratemporal fossa.
what is the maxillary artery a branch of?
terminal branch of the external carotid artery
what happens to the maxillary artery within the fossa?
gives rise to the middle meningeal artery, which travels into the cranial cavity via the foramen spinosum
how is the maxillary artery of clinical importance?
a site of traumatic bleed as the (anterior) middle meningeal (branch of maxillary) passes underneath the pterion (weakest point of skull)
venous plexus of the infratemporal fossa?
The pterygoid venous plexus
what is the pterygoid venous plexus connected to?
directly connected to the cavernous sinus, and drains the eye and its locality
clinical significance of connection of pterygoid venous plexus?
Infections of the skin and eye socket are able to track back into the plexus (drains eye), and on up into the cavernous sinus (connected directly) where meningitis is a substantial risk
aside from the pterygoid venous plexus, which other veins run within the infratemporal plexus?
the maxillary vein and middle meningeal vein (along with arteries)
what are the nerves running through the infratemporal fossa?
Mandibular nerve
Auriculotemporal, buccal, lingual and inferior alveolar nerves
Chorda tympani
Otic ganglion
what is mandibular nerve a branch of?
a branch of the trigeminal nerve (CN V)
where does mandibular nerve enter the infratemporal fossa?
via the foramen ovale, giving rise to motor and sensory branches
sensory branch of mandibular nerve?
continue inferiorly to provide innervation to some of the cutaneous structures of the face
what are Auriculotemporal, buccal, lingual and inferior alveolar nerves (branches of)?
sensory branches of the trigeminal nerve
what is chorda tympani a branch of?
a branch of the facial nerve (CN VII)
anatomical course of chorda tympani?
It follows the anatomical course of the lingual nerve
function of chorda tympani?
provides taste innervation to the anterior 2/3 of the tongue
what is the otic ganglion?
a parasympathetic collection of neurone cell bodies
where do nerve fibres leaving the otic ganglion travel?
Nerve fibres leaving otic ganglion ‘hitchhike’ along the auriculotemporal nerve to reach the parotid gland
