Ear Disorders

Question 1

What is the functional unit of the inner ear?

Answer 1

Organ of Corti

Question 2

What is the tympanic reflex?

Answer 2

Protection of the cochlea via muscle contraction in response to loud sounds

Question 3

T or F: The tympanic reflex will help protect your ears from gun shot sounds.

Answer 3

F; The reflex is not fast enough to protect the cochlea (designed for slow building sounds)

Question 4

T or F: You can listen and talk at the same time.

Answer 4

F; Muscle will contract while speaking (can’t hear others)

Question 5

How does sound produce stimulation in the cochlea hair cells?

Answer 5

• Sound waves cause vibration of the ossicles
• Ossicles (specifically Stapes) vibrates the basilar membrane at a complementary frequency

Question 6

From first bone to last, how are the osiccles vibrated from a sound wave?

Answer 6

1. Malleus
2. Incus
3. Stapes

Question 7

Where are different frequencies (high vs low) percieved along the basilar membrane?

Answer 7

• High: percieved towards the beginning of the basilar membrane
• Low: percieved towards the end of the basilar membrane

Question 8

How does persistant loud sounds affect hearing over time?

Answer 8

Loud sounds will damage the proximal portion of the basilar membrane leading to a loss of high pitch hearing over time.

Question 9

If a tumor exist in the ear, what pathologies might be observed?

Answer 9

Facial nerve suppression

Question 10

What are the 3 classifications of hearing loss? (Common differential)

Answer 10

• Conductive
• Sensorineural
• Mixed

Question 11

What are common differentials for diagnosis of Sensorineural hearing loss?

Answer 11

• Prebycusis
• Noise-induced
  
  • Temperature threshold shift > permanent
  • Acoustic trauma (one-time event)
• Ototoxicity
• Acoustic neuroma
• Menierie’s disease

Question 12

T or F: Patients with sensorineural hearing loss demonstrate AC>BC.

Answer 12

T; No change in conductive hearing should be observed

Question 13

What is Acoustic Neuroma?

Answer 13

Benign tumor of the acoustic nerve that commonly causes U/L sensorineural hearing loss

Question 14

How might a patient with Acoustic neuroma present?

Answer 14

Sudden onset U/L hearing loss with no outward/visible causes.

Question 15

What is commonly used to DX & TX Acoustic Neuroma?

Answer 15

DX: MRI/CT (pay attention to internal auditory canal)

TX: Steroids (prevent viral infection), Radiotherapy, Microsurgery

Question 16

What is the S/Sx triad associated with Menierés Disease?

Answer 16

• Rotational vertigo (At least one episode lasting 20+ minutes)
• Hearing loss (Fluctuating, low-frequency and progressive)
• Tinnitus

Question 17

What is Menierés disease?

Answer 17

Malfunction of endolymph volume regulation in the scala media (cochlear duct), results in:

• Disruption of basilar membrane movement
• Mixing of endoymph and perilymph

Question 18

What are dietary manipulations that can be useful in treating Menierés disease?

Answer 18

• Low sodium diet
• Water intake
• Caffeine restriction (includes chocolate)
• Alcohol restriction

Question 19

What is the common treatment for mild/moderate cases of Menierés disease?

Answer 19

Low Sodium diet and Low-dose dieuretic

Question 20

How does Weber testing present with conductive hearing loss?

Answer 20

Will lateralize to the affected ear

Question 21

How does Weber testing present in sensorineural hearing loss?

Answer 21

Will lateralize to the unaffected ear

Question 23

Why is tympanometry and important screening tool in evaluating a patient’s hearing?

Answer 23

evaluates details of middle ear function and middle ear reflexes for possible dysfunction

Question 24

What are the three main types of tympanograms found with tympanometry?

Answer 24

Type A: considered normal hearing, peak at 0 pressurization

Type B: observed with AOM, decreasing plateau

Type C: observed with negative pressure, one peak during negative pressurization

Question 25

How does otosclerosis affect a Type A tympanogram?

Answer 25

DEC amplitude (more rigid ear drum)

Question 26

If the ear drum is more flaccid, how will a Type A tympanogram change?

Answer 26

Amplitued of one peak will INC

Question 27

What are systemic causes of otitis externa?

Answer 27

• Seborrheic dermatitis
• Psoriasis
• Atopic dermatitis
• Lupus
• Acne

“SPALA”

Question 28

What are local causes of otitis externa?

Answer 28

Contact Dermatitis (i.e. topical anti-infectives, hearing aids, ear plugs)

Question 29

T or F: When cleansing the ear canal, do not flush unless the TM is fully visible.

Answer 29

T

Question 30

What other S/Sx should be evaluated for when managing otitis externa?

Answer 30

• Otitis media (esp. with URI or age <2 y/o)
• Fever (>101 °F)
• Severe pain or grandulation tissue
• Immune suppression (i.e. DM, corticosteroids, HIV)

Question 31

What topical treatments are avaiable for otitis externa?

Answer 31

• Acidification solution (with/without)
  
  • Homemade solution (1/3 distilled water, 1/3 white vinegar, 1/3 rubbing alcohol)
• ABX
  
  • Polymycin B/Neomycin
  • Gentamicin
  • Ofloxacin
  • Ciprofloxacin
  • Ciprodex

Question 32

What should be evaluated prior to using Polymycin B/Neomycin solutions for treatment of otitis externa?

Answer 32

R/O Allergies

Question 33

Why is Ofloxacin considered a good treatment for otitis externa? (think coverage)

Answer 33

Very effective against pseudomonas aeroginosa

Question 34

T or F: No oral ABX should be used to treat otitis externa.

Answer 34

T