week 1 anatomy ear

Question 1

what does the temporal bone contain?

Answer 1

Organs of hearing and balance

Facial (CN VII) and vestibulocochlear (CN VIII) nerves

Question 2

what is the Pterion?

Answer 2

H-shaped suture formed from Frontal, parietal, temporal
and sphenoid.

Thinnest part of skull, middle meningeal artery underlying. giving epidural haematoma

Question 3

3 fossa of base of the skull - what are they?

Answer 3

anterior
middle
posterior

Question 4

what makes up the anterior cranial fossa?

Answer 4

frontal, ethmoid & sphenoid

Question 5

what makes up the middle cranial fossa?

Answer 5

sphenoid and temporal

Question 6

what makes up the posterior cranial fossa?

Answer 6

temporal and occipital

Question 7

where does CNI exit skull?

Answer 7

cribriform plate of ethmoid

Question 8

what exits skull at superior orbital fissure?

Answer 8

CNIII, IV, V1, VI

Question 9

what exits the skull at foramen rotundum?

Answer 9

CN V2

Question 10

what exits the skull at foramen ovale?

Answer 10

V3

Question 11

what exits the skull at the optic canal?

Answer 11

V2

Question 12

what exits the skull at the intracranial opening of carotid?

Answer 12

CN 7, 8

Question 13

what exits the skull at the the jugular foramen?

Answer 13

CN 9, 10, 11, internal jugular vein

Question 14

where does CN XII exit the skull?

Answer 14

hypoglosssal canal

Question 15

what is the external ear? function ?

Answer 15

auricle to tympanic membrane
via external acoustic meatus

collects and conveys sound waves to tympanic membrane

Question 16

what is the middle ear? function ?

Answer 16

tympanic membrane to oval window
contains eustachian tube

amplifies & conducts sound waves to the internal ear

Question 17

what is the inner ear? function ?

Answer 17

oval window to internal acoustic meatus

converts special sensory information:into fluid waves, then APs, conducts APs to brain

Question 18

sensory supply to the ear/auricle?

Answer 18

helix= c2, 3

inferior parts of EAM & tympanic membrane=vagus

inner (spots)= facial

superior parts of EAM & most of the tympanic membrane= CN v3

Question 19

lymphatics drainage of the auricle. [where to they eventually drain to?]

Answer 19

Lateral surface of superior half=parotid lymph nodes

Cranial surface of superior half=mastoid lymph nodes (and deep cervical)

Rest of auricle, including lobe
=superficial cervical lymph nodes

[deep cervical lymph nodes (in carotid sheath); then thoracic duct or right lymphatic duct; then venous angle]

Question 20

describe the ‘skeleton of the external ear?’

Answer 20

temporal bone

elastic cartilage = avascular hyaline, so gets nutrients from skin.

Question 21

what is another name for the ear canal? what is it made up of? what does it produce?

Answer 21

external acoustic meatus

1/3 cartilage, 2/3 bony + lined with skin

produces earwax via ceruminous glands

Question 22

which direction to pull ear in otoscopic exam in adult?

Answer 22

gently pull auricle posterosuperiorly

Question 23

which direction to pull ear in otoscopic exam in child?

Answer 23

gently pull auricle posteroinferiorly (careful not to damage tympanic membrane)

Question 24

what does the Glossopharyngeal nerve (CN IX) provide general sensory nerve supply to concerning the ear?

Answer 24

middle ear cavity
eustachian tube
nasopharynx
oropharynx
tonsils

Question 25

what supplies the tympanic membrane?

Answer 25

external surface: mostly CN V3 (auriculotemporal branch) internal surface: CN IX

Question 26

what two points does the eustachian tube connect?

Answer 26

the tympanic cavity to the lateral wall of the nasopharynx

Question 27

what are the three bones (auditory ossicles) of the inner ear? how do they articulate?

Answer 27

malleus incus stapes articulate via synovial joints

Question 28

where does the malleus rest and the base of the stapes attach to?

Answer 28

inner surface of ear drum fits into the oval window (way into inner ear)

Question 29

what are the other names for the Eustachian Tube. what does it connect?

Answer 29

Auditory tube, pharyngotympanic tube connects middle ear cavity to nasopharynx

Question 30

why is the Eustachian Tube clinically important?

Answer 30

bacteria/viruses can spread between the two i.e. from pharynx/tonsils pain and hearing loss tonsillitis or pharyngitis can mimic ‘earache’ common example of referred pain

Question 31

the middle and inner ear and both in what part of the temporal bone?

Answer 31

petrous

Question 32

STOPPED AT SLIDE 14 why?

Answer 32

I've given up tonight :P

Question 33

what is the pinna?

Answer 33

whole out visible outer ear (AKA auricle)

Question 34

what is the helix? trigus?

Answer 34

outer parts of ear infolding