The Ear

Question 1

Where would one find the vestibule-cochlear apparatus?

Answer 1

Petrous temporal bone

Question 2

Describe the structure of the external ear what innervate it?

Answer 2

Auricle and external accoustic meatus composed of cartilage and bone, that leads sound waves towards the tympanic membrane

Auricle shaped to funnel sound

Innervated by greater auricular and auriculotemporal

Question 3

Describe the middle ear

Answer 3

Ossicles mechanically transmit sound. Connected to the pharynx by the auditory tube

Question 4

Describe the inner ear basically

Answer 4

Semi-circular canals and cochlea converting mechanical signals to electrical signals, carried by Vestibulocochlear nerve

Question 5

What is the tympanic membrane?

Answer 5

Membrane held within temporal bone by a fibrocartilaginous ring

Lies at an angle facing slightly downwards and anteriorly. It is concave at the Umbro for attachment of the malleus

Question 6

Label the middle ear bones

Answer 6

Stapes

Incus

Malleus

Question 7

Describe the form and position of the auditory tube

What does it do?

Answer 7

Connects middle ear with Nasopharynx

Initially a bony canal but becomes cartilaginous between petrous temporal and greater wing of sphenoid

For pressure equalisation between middle ear and atmospheric pressure

Question 8

Where is there a risk of infection spread in the ear?

Answer 8

Auditory tube connected to the nasopharynx

Thin roof of bone between middle ear and the middle cranial fossa

Question 9

What is otitis media?

Answer 9

Infections in the middle ear and often caused by obstruction of the auditory tube

Chronic infections may damage ossicles causing deafness

Question 10

What fluid is housed within the inner ear?

Answer 10

Perilymph is housed within the vestibule, semicircular canals, and cochlea,

Within perilymph is endolymph