The ear

Question 1

What is the pathology of auditory exstosis?

Answer 1

This is surfers ear that results in multiple bilateral bony swellings of the canal resulting from repeated cold water exposure. Can cause repeated infections when canal becomes too small for migration of wax and debris. This requires surgical removal.

Question 2

What type of hearing loss requires urgent referral?

Answer 2

Sudden sensorineural hearing loss

Question 3

What types of hearing loss will rinnes and webers tests indicate?

Answer 3

Rinnes test is when the fork is pressed to the mastoid and then held next to the ear. If the mastoid is louder then this shows a conductive deafness.
Webers test is when the fork is put on the forehead. If the sound localises to the affected side then this is conductive hearing loss. If the sound localises to the contralateral ear then this is sensorineural hearing loss.

Question 4

how is hearing most commonly tested?

Answer 4

Using pure tone audiometry from headphones in a soundproofed room

Question 5

How is hearing test done in babies?

Answer 5

Look for otoacoustic emissions from the outer hair cells

This is because normally they move to ampify sounds so this can be detected if they are normal

Question 6

How is the pressure of the middle ear usually measured?

Answer 6

Using tympanometry or an impedance audiogram - measuring pressure in canal to assess middle ear

Question 7

What is a normal tympanogram and how do these change in pathology?

Answer 7

Normally have a peak with normal compliance

Fluid in the middle ear causes a flat line as it reduces the compliance

Question 8

What are some of the common causes of otalgia?

Answer 8

50% is referred pain from elsewhere
Ears:
-Otitis externa
-otitis media
-furunculosis
-barotrauma
-cholestiatoma
Referred:
-CN V - dental disease of TMJ dysfunction
-CN VII - facial nerve refers pain in herpes
-CN IX and X - pain referred from posterior thrid of the tongue e.g. post tonsilectomy

Question 9

What are the causes of otitis externa?

Answer 9

Excess canal moisture e.g. regular swimming
Trauma from fingernails
Absence of wax
Main organism is pseudomonas but staph aureus is also common

Question 10

What are the symptoms of otitis externa?

Answer 10

Ear pain
Discharge
itch
tragal tenderness

Question 11

How is otitis externa treated?

Answer 11

Mild cases can be given acetic acid
Moderate cases need topical antibiotic +/- steroid drops
In severe OE the ear canal is excluded and need to insert thin aluminium acetate ear wick which will allow it to open over a few days

Question 12

What is a contraindication of topical aminoglycosides in otitis externa?

Answer 12

Perforation or patent grommit due to the risk of ototoxicity

Question 13

What is a furunculosis?

Answer 13

This is a painful hair follicle staphlococcus abcess

Question 14

What is the treatment of necrotising otitis externa?

Answer 14

Develops most commonly in diabetics and is life threatening.

Treatment is surgical debridement, systemic antiobiotics and specific immunoglobulins

Question 15

What are the clinical features of TMJ dysfunction?

Answer 15

Earache, joint clicking/popping, joint tenderness exacerbated by movement

Question 16

What is the treatment for TMJ dysfunction?

Answer 16

Usually just require analgesia and reassurance that it will resolve

Question 17

What are the methods for clearing the external auditory canal?

Answer 17

Gentle irrigation if no perforation
Dry mopping using a jobson horne probe
Microsuction in ENT

Question 18

What is the character of discharge from the different parts of the ear?

Answer 18

External ear inflammation causes a scanty discharge (small amount)
Middle ear discharges mucous
Offernsive discharge suggests cholesteotoma
CSF leak may occur after trauma, will show halo sign on filter paper

Question 19

How does acute otitis media usually present?

Answer 19

With pain, discharge, fever or vomiting following a viral URTI
Bulging drum is painful which eases when the drum perforates and there is discharge

Question 20

What organisms typically cause otitis media?

Answer 20

Pneumococcus and other streps ad staphs

Question 21

What is the treatment for otitis media?

Answer 21

60% resolve in 24 hours without antibiotics so optimise analgesia
If it has been ongoing for >4 days or systemically unwell then given antibiotics
Amoxicillin 40mg/kg/day for 5 days

Question 22

What are the types of chronic otitis media and what is the treatment?

Answer 22

There is dry - drum perforation without active infection
Chronic serous otitis media - continous serous drainage (straw coloured)
Chronic suppurative otitis media - persistent purulent drainage through the tympanic membrane
Treated with systemic antibiotics dependent on sensitivites

Question 23

What is a cholesteatoma? How is it treated?

Answer 23

This is a problem that develops from repeated otitis media infections. It causes release of lytic enzymes locally around the ear drum causing damage. It is treated with mastoid surgery to remove it

Question 24

What are the signs and treatment of mastoiditis?

Answer 24

Signs: fever, tenderenss and redness over mastoid, protruding pinna
Treatment is with antibiotics with mastoidectomy in more severe cases

Question 25

What is a myringoplasty?

Answer 25

Repair of the tympanic membrane often from temporalis fascia, this allows a scaffold for the earfrum to grow onto

Question 26

What are the clinical features of otitis media with effusion?

Answer 26

There is hearing loss due to the middle ear being full of fluid. This is usually from eustaion tube blockage. children may have poor speech and language. On examination there may be a fluid level or bubbles behind the drum.

Question 27

What is the treatment of otitis media with effusion?

Answer 27

Usually 3 month period of observation followed by autoinflation of the eustation tube. If this does not work then consider grommets

Question 28

What are the percentages for the causes of childhood hearing loss? genetic, non genetic and idiopathic?

Answer 28

50% genetic
25% non genetic
25% idiopathic

Question 29

What are the newborn hearing screening tests?

Answer 29

otoacoustic emissions - tiny sounds preoduced by the outer hair cells as they amplify sounds
Audiological brainstem responses - electrodes pick up infant brain activity

Question 30

How does a cochlear implant work?

Answer 30

By directly stimulating the auditory nerve in the cochlear

Question 31

What are some of the causes of obstructive hearing loss in adults?

Answer 31

There could be blockage of the ear canal e.g. wax, pus, foreign body
Drum perforation - trauma, infection
Problems with ossicular chain e.g. otosclerosis, infection
Eustachian tube problems e.g. effusion secondary to nasopharangeal carcinoma

Question 32

What are some of the causes of sensorineural hearing loss in adults?

Answer 32

These are problems central to the oval window in the cochlear
Ototoxic drugs - gentomycin, vancomycin, hydrochloroquine
Postinfective - measles, mumps, flu
Cochlear vascular disease
Menieres disease
trauma

Question 33

What is the management of sudden sensorineural hearing loss in adults?

Answer 33

Tkae full history and examine EAC and TM to exclude wax/effusion. Perform tuning fork tests
Get expert ENT help
Look for causes in bloode.g. drugs, mumps, acoustic neuroma
Cause only found in 10%
Arrange audiology
Treatment depends on cause if found
Usually high dose prednisolone 80mg/24hrs for 4 days then tapered over 8 days, this presumes it is an infective cause
May be response to hyperbaric O2 if given promptly