ENT Pathophysiology

Question 1

Anotia

Answer 1

absence of the ear

Question 2

hidden or “pocket ear.”

Answer 2

Cryptotia

Question 3

Microtia

Answer 3

Tiny ear: diminutive ear (fetal alcohol
syndrome, gestational
diabetes, thalidomide and
isotretinion exposure).
*Often have severe conductive hearing loss

Question 4

Polyotia

Answer 4

“mirror ear”

Question 5

Stahl’s Ears

Answer 5

Pointed ear shape, can be reshapen

Question 6

The Cochlea is Housed in the bony labyrinth of the ____ bone

Answer 6

temporal

Question 7

Vibrations of the skull –> vibrations in cochlear _____

Answer 7

fluid

Question 8

Sound wave conduction

Answer 8

Malleus, incus, stapes, oval window, scala vestibulli, movement of fluid

Question 9

Fibrous membrane separating the scale tympani from scala media

Answer 9

Basilar Membrane

Question 10

Low frequency sounds pass
farther in the cochlea through
the _____

Answer 10

perilymph

Question 11

Translates sound waves into nerve impulses

Answer 11

The Organ of Corti

Question 12

When basilar fibers bend toward scala
vestibuli the hair cells depolarize:

Answer 12

• Mechanical transduction of the cilia
• Opens K+ channels
• K+ flows from scala media fluid into the stereocilia
• Leads to depolarization and opening of voltage-gated calcium channels
• Ca++ flow in, augmenting depolarization and stimulating release of Glutamate

Question 13

_____ Americans have some form of hearing loss

Answer 13

50 million

Question 14

Most common causes of hearing loss

Answer 14

• cerumen impaction,
• eustachian tube dysfunction,
• age-related

Question 15

Function of the Eustachian Tube and what happens if it is blocked?

Answer 15

1) Air-pressure equalizing valve
2) Drain for mucus lining the middle ear
If blocked → middle ear: air pocket → forms vacuum pulling ear drum inward

Question 16

2 Components of the Vestibular System

Answer 16

Semicircular Canal System: indicate rotational movements
Otoliths: indicate linear accelerations

Question 17

5 specific sensory zones

Answer 17

• The utricle and the saccule have flat
  plaques of sensory hair cells called
  maculae (2).
• The ampulla of the semicircular canals contain saddle-like ridges with sensory hair cells called crests (3; aka crista ampullaris).

Question 18

The ____ or the otolith membrane is a gelatinous projection into the lumen of
the ampulla, utricle and saccule that allows for easier deflection of the stereocilia of the sensory cells

Answer 18

cupula

Question 19

Cupula is topped with _____

Answer 19

otolith stones

Question 21

Vestibulo-ocular Reflex (VOR)

Answer 21

• Reflexive eye movement that stimulates the extraocular muscles by
  the vestibular system
• Stabilizes images on the retina during head movement

Question 22

A subjective sense of
rotation of either self or
environment

Answer 22

Vertigo

Question 23

BPPV

Answer 23

benign paroxsymal
positional vertigo)

Question 24

calcium carbonate crystals
dislodge and migrate into
semicircular canals, occurs in

Answer 24

BPPV

Question 25

Types of Epistaxis

Answer 25

1. Anterior epistaxix: most common and less severe, easier to control
   - Kisselbach’s plexus/little’s plexus
2. Posterior epistaxix: less common, more severe and difficult to control
   - sphenopalatine artery

Question 26

Three cell types in smell sensation

Answer 26

olfactory sensory neurons, supporting (sustentacular) cells, and basal stem cells

Question 27

_____ bind specific odorant
receptors on the cilia to initiate a
cascade that leads to an action
potential (AP) from the sensory neuron

Answer 27

Odorants

Question 28

The olfactory epithelium covers ____ of the roof of the nasal cavity.

Answer 28

5- 10 cm2

Question 29

Nystagmus

Answer 29

• Rhythmic, involuntary oscillations of the eyes
  (horizontal, vertical, torsion, combinations of any of
  the above, unilateral or bilateral)

Question 30

Slow vestibular-induced eye movements are interrupted by quick movements in the opposite direction, With what

Answer 30

Nystagmus

Question 31

Rhinitis

Answer 31

• Inflammation of the mucus membranes of the nasal cavity
• Congestion, runny nose, sneezing, post
  -nasal drip
• Caused by viruses, bacteria and most
  commonly allergens (pollen, dander)
• Immune hypersensitivity

Question 32

Laryngeal Muscles
move laryngeal
cartilages to _____

Answer 32

affect
position of vocal folds