External ear (dave's notes)

Question 1

Two words used for the external ear

Answer 1

Auricle/pinna

Question 2

What does the auricle or pinna consist of?

Answer 2

A skeleton of resilient yellow cartilage, with vestigial intrinsic and extrinsic muscles supplied by the facial nerve

Question 3

Describe the external acoustic meatus - length/wall size

Answer 3

~3cm long with the anteroinferior wall the longest and the posterosuperior wall the shortest

Question 4

What tissues does the external acoustic meatus consist of?

Answer 4

Outer 1/3rd cartilage, inner 2/3rds bone

Question 5

What is the boney part of the external acoustic meatus formed from?

Answer 5

The tympanic part of the temporal bone

Question 6

What is the cartilaginous part of the external acoustic meatus rich in?

Answer 6

Hair and sebaceous glands

Question 7

What is the arterial supply of the external ear and external acoustic meatus?

Answer 7

The posterior auricular and superficial temporal arteries

Question 8

What is the nerve supply to the external ear and external acoustic meatus?

Answer 8

Great auricular, auriculotemporal, vagus and facial