Infratemporal fossa

Question 1

what is the infratemporal fossa?

Answer 1

a complex and irregularly shaped space (wedge shape), located deep to the masseter muscle

Question 2

function of infratemporal fossa?

Answer 2

The infratemporal fossa acts as a pathway for neurovascular structures passing between the cranial cavity, pterygopalatine fossa and temporal fossa

Question 3

where is the infratemporal fossa located?

Answer 3

It is located deep to the masseter muscle and zygomatic arch (to which the masseter attaches)

Question 4

what is the infratemporal fossa connected to? by?

Answer 4

the pterygopalatine fossa by the pterygomaxillary fissure and also communicates with the temporal fossa superiorly

Question 5

what forms the boundaries of the infratemporal fossa?

Answer 5

bone and soft tissue

Question 6

lateral border of infratemporal fossa?

Answer 6

ramus of the mandible

Question 7

medial border of infratemporal fossa?

Answer 7

lateral pterygoid plate of the sphenoid

Question 8

anterior border of infratemporal fossa?

Answer 8

posterior surface of the maxilla

Question 9

posterior border of infratemporal fossa?

Answer 9

carotid sheath

Question 10

floor of the infratemporal fossa?

Answer 10

medial pterygoid muscle

Question 11

roof of infratemporal fossa?

Answer 11

the greater wing of the sphenoid bone

Question 12

what opens out onto the roof of the infratemporal fossa?

Answer 12

Two foramina open out on the roof:
foramen ovale
foramen spinosum

Question 13

function of foramen ovale and foramen spinosum on the roof of infratemporal fossa?

Answer 13

They provide a connection with the cranial cavity

Question 14

how do you figure out where the infratemporal fossa is?

Answer 14

clench jaw and feel for masseter muscle in cheek (this is above the fossa)

Question 15

contents of the infratemporal fossa?

Answer 15

3 muscles (of mastication)
1 artery
1 venous plexus
nerves

Question 16

what are the muscles within the infratemporal fossa?

Answer 16

superior + inferior heads lateral pterygoid muscles (within fossa)
superficial + deep heads of medial pterygoid (within fossa)
inferior temporalis muscle

Question 17

artery of the infratemporal fossa?

Answer 17

The maxillary artery travels through the infratemporal fossa.

Question 18

what is the maxillary artery a branch of?

Answer 18

terminal branch of the external carotid artery

Question 19

what happens to the maxillary artery within the fossa?

Answer 19

gives rise to the middle meningeal artery, which travels into the cranial cavity via the foramen spinosum

Question 20

how is the maxillary artery of clinical importance?

Answer 20

a site of traumatic bleed as the (anterior) middle meningeal (branch of maxillary) passes underneath the pterion (weakest point of skull)

Question 21

venous plexus of the infratemporal fossa?

Answer 21

The pterygoid venous plexus

Question 22

what is the pterygoid venous plexus connected to?

Answer 22

directly connected to the cavernous sinus, and drains the eye and its locality

Question 23

clinical significance of connection of pterygoid venous plexus?

Answer 23

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

Question 24

aside from the pterygoid venous plexus, which other veins run within the infratemporal plexus?

Answer 24

the maxillary vein and middle meningeal vein (along with arteries)

Question 25

what are the nerves running through the infratemporal fossa?

Answer 25

Mandibular nerve Auriculotemporal, buccal, lingual and inferior alveolar nerves Chorda tympani Otic ganglion

Question 26

what is mandibular nerve a branch of?

Answer 26

a branch of the trigeminal nerve (CN V)

Question 27

where does mandibular nerve enter the infratemporal fossa?

Answer 27

via the foramen ovale, giving rise to motor and sensory branches

Question 28

sensory branch of mandibular nerve?

Answer 28

continue inferiorly to provide innervation to some of the cutaneous structures of the face

Question 29

what are Auriculotemporal, buccal, lingual and inferior alveolar nerves (branches of)?

Answer 29

sensory branches of the trigeminal nerve

Question 30

what is chorda tympani a branch of?

Answer 30

a branch of the facial nerve (CN VII)

Question 31

anatomical course of chorda tympani?

Answer 31

It follows the anatomical course of the lingual nerve

Question 32

function of chorda tympani?

Answer 32

provides taste innervation to the anterior 2/3 of the tongue

Question 33

what is the otic ganglion?

Answer 33

a parasympathetic collection of neurone cell bodies

Question 34

where do nerve fibres leaving the otic ganglion travel?

Answer 34

Nerve fibres leaving otic ganglion ‘hitchhike’ along the auriculotemporal nerve to reach the parotid gland