Ear-external Auditory Canal,ossicles,embryology

Question 1

Darwin’s tubercle

Answer 1

Variation seen in some people

Conical elevation on helix

Question 2

Embryology of external auditory canal

From where does it develop from

Answer 2

Develop from first brachial cleft

Question 3

Eustachian tube and middle ear develop from

Answer 3

First brachial pouch

Question 4

Tympanic membrane embryology

Answer 4

Derives from all three germ layers

Question 5

Which are the openings in collaural fistula

Answer 5

First opening in floor of EAC

Second opening close to angle of mandible

Question 6

Malleus and incus derived from

Answer 6

First arch

Question 7

Stapes embryology

Answer 7

Head – second arch

Footplate – otic capsule

Question 8

Cochlea Embryology

Answer 8

Derived from otic capsule

Question 9

When does the full development of ear happen

Answer 9

20th week

Question 10

Otic Capsule gives rise to what

Answer 10

Pars superior – development of semicircular canal and utricle
Pars inferior – cochlea and saccule

Question 11

Most common congenital inner ear developmental abnormality

Answer 11

Schiebe’s Dysplasia – cochleosaccular dysplasia

Question 12

Mondini’s Dysplasia

Answer 12

Cochlea turn only 1 1/2

Causes congenital deafness

Question 13

Michel’s aplasia

Answer 13

Absent cochlea

Deaf since birth