3. Clinical Aspects Of Middle & External Ear

Question 1

What forms the pinna during development?

Answer 1

Six hillocks of His from the first and second pharyngeal arches

Question 2

Which pharyngeal cleft forms the external auditory canal?

Answer 2

First pharyngeal cleft

Question 3

Which pharyngeal pouch forms the middle ear cavity?

Answer 3

First pharyngeal pouch

Question 4

Which ossicles arise from the first pharyngeal arch?

Answer 4

Malleus and incus

Question 5

Which ossicle arises from the second pharyngeal arch?

Answer 5

Stapes

Question 6

What is the origin of the tympanic membrane layers?

Answer 6

Ectoderm (outer), mesoderm (middle), endoderm (inner)

Question 7

What is a collaural fistula?

Answer 7

An abnormal connection between the external auditory canal and the neck

Question 8

What is the significance of Korner’s septum?

Answer 8

Persistent petrosquamous suture that can complicate mastoid surgery

Question 9

At what age does the mastoid process develop?

Answer 9

Around 2 years of age

Question 10

What is the embryological origin of the auricle?

Answer 10

First and second pharyngeal arches