Ear and Infratemporal Fossa

Question 1

Sensory innervation of the external ear

Answer 1

Auricle: superficially by cervical plexus and V3, deeper by vagus and facial
External acoustic meatus: V3, vagus and facial
Tympanic membrane: outer by V3, vagus, facial and glossopharyngeal, inner by glossopharyngeal

Question 2

Two parts of the middle ear

Answer 2

Tympanic cavity and epitympanic recess

Question 3

The roof of the middle ear is called __________ and separates the middle ear from _____________

Answer 3

The roof of the middle ear is called the tegmental wall and separates the middle ear from the middle cranial fossa

Question 4

The floor of the middle ear is called __________ and separates the middle ear from _________

Answer 4

The floor of the middle ear is called the jugular wall and separates the middle ear from the internal jugular vein

Question 5

The lateral wall of the middle ear is called __________ and separates the middle ear from _____________

Answer 5

The lateral wall of the middle ear is called the membranous wall and separates the middle ear from the external ear

Question 6

The posterior wall of the middle ear is called __________ and separates the middle ear from _____________

Answer 6

The posterior wall of the middle ear is called the mastoid wall and separates the middle ear from the mastoid air cells and continues to the mastoid antrum

Question 7

The anterior wall of the middle ear is called __________ and separates the middle ear from _____________

Answer 7

The anterior wall of the middle ear is called the carotid wall and separates the middle ear from the internal carotid artery

Question 8

The medial wall of the middle ear is called __________ and separates the middle ear from _____________

Answer 8

The medial wall of the middle ear is called the and separates the middle ear from the inner ear

Question 9

Promontory

Answer 9

Produced by the basal coil of the cochlea

Covered by mucous membrane and contains the tympanic plexus

Question 10

What enters the middle ear through the mastoid wall?

Answer 10

The tendon of the stapedius and the chorda tympani

Question 11

What enters the middle ear through the carotid wall?

Answer 11

The eustachian tube and the tensor tympani muscle

Branches from the internal carotid plexus

Question 12

What exits the middle ear through the carotid wall?

Answer 12

The chorda tympani

Question 13

What enters the middle ear through the jugular wall?

Answer 13

A branch of the glossopharyngeal nerve

Question 14

What exits the middle ear through the labyrinthine wall?

Answer 14

Lesser petrosal nerve

Question 15

Innervation of the middle ear

Answer 15

Tympanic plexus

Question 16

Blood supply of the middle ear

Answer 16

Tympanic branch of maxillary artery and mastoid branch of occipital or posterior auricular arteries

Question 17

Things to label on a picture of the tympanic membrane

Answer 17

Posterior malleolar fold
Pars flaccida
Lateral process of malleus
Handle of malleus
Anterior malleolar fold
Cone of light
Umbo

Question 18

Contents of the middle ear

Answer 18

Auditory ossicles
Muscles associated with the ossicles
Tympanic nerve plexus (tympanic branch of CN IX and caroticotympanic nerves of internal carotid plexus)

Question 19

What structure is often injured during middle ear surgery?

Answer 19

Chorda tympani - leads to changes in taste and dryness of the mouth

Question 20

Ossicles

Answer 20

Malleus, incus, stapes

Question 21

Muscles associated with ossicles

Answer 21

Tensor tympani (CN V3)
Stapedius (CN VII)

Question 22

Medial wall of infratemporal fossa

Answer 22

Lateral plate of pterygoid process, pharynx, tensor veli palatine, levator veli palatine

Question 23

Lateral wall of infratemporal fossa

Answer 23

Medial surface of ramus of mandible

Question 24

Anterior wall of infratemporal fossa

Answer 24

Posterior surface of maxila

Question 25

Roof of infratemporal fossa

Answer 25

Greater wing of sphenoid and temporal bone

Question 26

Major contents of the infratemporal fossa

Answer 26

``` Sphenomandibular ligament Lateral and medial pterygoid muscles Maxillary artery CN V3 Pterygoid venous plexus CN IX CN VII branches ```

Question 27

Maxillary artery in the infratemporal fossa

Answer 27

Major branch of external carotid artery Originates adjacent to neck of mandible runs forward through the infratemporal fossa and gives off deep temporal, masseteric, buccal and pterygoid branches

Question 28

4 muscles of mastication

Answer 28

Masseter, temporalis, medial pterygoid and lateral pterygoid

Question 29

Masseter

Answer 29

Originates from zygomatic arch and maxillary process of zygomatic bone Inserts at coronoid process of mandible Innervated by CN V3

Question 30

Medial pterygoid muscle

Answer 30

Originates from lateral pterygoid plate and inserts at medial angle of mandible Innervated by CN V3

Question 31

Lateral pterygoid muscle

Answer 31

Originates from lateral pterygoid plate and inserts at condyloid process of mandible Innervated by CN V3

Question 32

Temporalis

Answer 32

Originates at sphenoid bone and inserts at coronoid process of mandible Innervated by CN V3

Question 33

Openings of the pterygopalatine fossa

Answer 33

``` Foramen rotundum Pterygoid canal Palatovaginal canal Palatine canal Sphenopalatine foramen Inferior orbital fissure ```

Question 34

Sphenopalatine artery

Answer 34

Runs through sphenopalatine foramen in the medial wall of the pterygopalatine fossa Responsible for chronic epistaxis

Question 35

Borders of the pterygopalatine fossa

Answer 35

Sphenoid (posterior), palatine (medial) and maxilla (anterior) bones

Question 36

How are the pterygoid muscles named?

Answer 36

In relation to the lateral pterygoid plate

Question 37

Contents of the pterygopalatine fossa

Answer 37

Maxillary nerve Maxillary artery Greater petrosal branch of facial nerve Deep petrosal branch of carotid plexus

Question 38

Pterygoid ganglion

Answer 38

Also known as the hayfever ganglion | Receives autonomic nerves carried by the nerve of the pterygoid canal

Question 39

Maxillary nerve

Answer 39

Purely sensory Enters pterygopalatine fossa from middle cranial fossa through foramen rotundum Gives off zygomatic and posterior superior alveolar branches Becomes infraorbital nerve when it passes through the inferior orbital fissure

Question 40

Infraorbital nerve branches

Answer 40

Middle, anterior and superior alveolar nerves which innervate the upper teeth, maxillary sinus and nasal cavity

Question 41

Posterior superior alveolar nerve

Answer 41

Supplies upper molar teeth, gingivae and maxillary sinus

Question 42

Maxillary artery branches in the ptergyopalatine fossa

Answer 42

Zygomatic artery Posterior superior alveolar artery Infraorbital artery Anterior superior alveolar arteries

Question 43

The sphenopalatine artery is a continuation of:

Answer 43

The maxillary artery