Ear

Question 1

What is the skin of the concha innervated by?

Answer 1

VII, IX, and X

Question 2

What is the blood supply to the pinna?

Answer 2

superficial temporal a and posterior auricular a

Question 3

What can trauma to the pinna cause in the subcutaneous tissue?

Answer 3

hemorrhaging
auricular hematoma
cauliflower ear?

Question 4

What are the 3 layers of the tympanic membrane ?

Answer 4

skin, pars tensa (majority) / pars faccida, and inner mucous membrane

Question 5

What innervates the layers of the tympanic membrane?

Answer 5

skin - GSA V, X

inner mucous membrane - GVA IX via tympanic plexus

Question 6

What is the path of the chorda tympani in the ear?

Answer 6

runs through anterior and posterior mallear folds. crosses neck of malleus

Question 7

What is otitis media?

Answer 7

occurs in infants and children.
accumulation of fluids and mucosa
Decreases hearing
happens in children bc auditory tubes are horizontal and impedes drainage

Question 8

What can occur if there is a fracture of the petrous?

Answer 8

basilar skull fracture such as transverse or longitudinal fractures of temporal base can cause:
otorrhea, otorrhagia, and deafness
Bell’s palsy may result
some brain damage -> death

Question 9

Describe the path of the facial n in the ear?

Answer 9

travels laterally in the internal auditory meatus before entering the facial canal
It turns sharply at the level of the geniculate ganglion = external genu
sends branch to stapedius m
exits sytlomastoid foramen

Question 10

What is otosclerosis?

Answer 10

ossification or scarring of small ossicular joints

prevents transmission of sound
bone conduction test is NORMAL
nerve conduction test is ABNORMAL

Question 11

Describe the tensor tympani m path, innervation and action

Answer 11

tendon loops laterally around processus cochleariformis and inserts into malleus

I: V3

Tightens and attenuates tympanic membrane vibrations

Question 12

What is the action and innervation of stapedius m?

Answer 12

VII

Pulls stapes out of fenestra vestibuli protectiton mechanism

Question 13

What is the sensory innervation of middle ear mucosal lining ?

Answer 13

GVA of IX via tympanic plexus

Question 14

What is the innervation of the organ of corti?

Answer 14

VIIIc

Question 15

What does the VIIIv innervate?

Answer 15

maculae utricle and saccule and cristae ampullaris

Question 16

What is the processus cochleariformis?

Answer 16

bony pulley that the tendon of the tensor tymapni m loops before inserting on the manubrium of the malleus

Question 17

What is the promontory ?

Answer 17

formed by basal turn of the cochlea and covered by the tympanic plexus (IX) and caroticotymapnic n

Question 18

What artery in the ear can cause vertigo and nausea if there is atherosclerosis?

Answer 18

labryinthine a

br of AICA

Question 19

What does the cochlear pass through?

Answer 19

Modiolus - bony core of cochlea

Question 20

What does prolong exposure to excessive amounts of noise and music lead to?

Answer 20

partial destruction of the organ of corti

Question 21

What is the innervation of the pinna?

Answer 21

GSA sensory by the auriculotemporal n (V3)

Lesser occipital and greater auricular n.