W21-L7: Ear and Auditory Tube

Question 1

What is the role of the auricle?

Answer 1

collects sound

Question 2

What is the lateral 1/3 of the external acoustic meatus and what is the medial 2/3?

Answer 2

Lateral 1/3=Cartilagenous

Medial 2/3= Temporal bone

Question 3

What nerve innervates the posteroinferior surface of the external acoustic meatus?

Answer 3

Vagus

Question 4

What nerve innervates the anterosuperior surface of the external acoustic meatus and external surface of tympanic membrane?

Answer 4

Auriculotemporal nerve (V3)

Question 5

What shape is the external surface of the tympanic membrane?

Answer 5

Concaved

Question 6

Where is the cone of light on the external surface of the tympanic membrane?

Answer 6

Anterio-inferior

Question 7

Where is the Epitympanic recess and where does it go?

Answer 7

Superior to tympanic membrane, connects to mastoid air cells

Question 8

Where is the tympanic cavity proper?

Answer 8

Directly medial to the tympanic membrane

Question 9

What are the ossicles called?

Answer 9

Stapes, Incus and Malleus

Question 10

What muscle is on the anterior aspect of the medial wall of middle ear?

Answer 10

Tensor Tympani (CN V)

Question 11

What does the tensor tympani attach to?

Answer 11

Malleus

Question 12

What muscle is on the posterior aspect of the medial wall of middle ear?

Answer 12

Stapedius muscle (CN VII)

Question 13

What does the Stapedius muscle attach to?

Answer 13

Stapes

Question 14

What is the bony labyrinth filled with?

Answer 14

Peri-lymph

Question 15

What is the Membranous labyrinth filled with?

Answer 15

endolymph

Question 16

What are the there semi-circular ducts?

Answer 16

Anterior, Horizontal and Posterior

Question 17

Where are the ampulla situated and what do they sense?

Answer 17

Base of the semi-circular ducts which sense dynamic changes in equilibrium

Question 18

Where are high frequency’s represented on the cochlear duct?

Answer 18

Base, low frequency at the apex