The ear Flashcards
What is the pathology of auditory exstosis?
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.
What type of hearing loss requires urgent referral?
Sudden sensorineural hearing loss
What types of hearing loss will rinnes and webers tests indicate?
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.
how is hearing most commonly tested?
Using pure tone audiometry from headphones in a soundproofed room
How is hearing test done in babies?
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
How is the pressure of the middle ear usually measured?
Using tympanometry or an impedance audiogram - measuring pressure in canal to assess middle ear
What is a normal tympanogram and how do these change in pathology?
Normally have a peak with normal compliance
Fluid in the middle ear causes a flat line as it reduces the compliance
What are some of the common causes of otalgia?
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
What are the causes of otitis externa?
Excess canal moisture e.g. regular swimming
Trauma from fingernails
Absence of wax
Main organism is pseudomonas but staph aureus is also common
What are the symptoms of otitis externa?
Ear pain
Discharge
itch
tragal tenderness
How is otitis externa treated?
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
What is a contraindication of topical aminoglycosides in otitis externa?
Perforation or patent grommit due to the risk of ototoxicity
What is a furunculosis?
This is a painful hair follicle staphlococcus abcess
What is the treatment of necrotising otitis externa?
Develops most commonly in diabetics and is life threatening.
Treatment is surgical debridement, systemic antiobiotics and specific immunoglobulins
What are the clinical features of TMJ dysfunction?
Earache, joint clicking/popping, joint tenderness exacerbated by movement
What is the treatment for TMJ dysfunction?
Usually just require analgesia and reassurance that it will resolve
What are the methods for clearing the external auditory canal?
Gentle irrigation if no perforation
Dry mopping using a jobson horne probe
Microsuction in ENT
What is the character of discharge from the different parts of the ear?
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
How does acute otitis media usually present?
With pain, discharge, fever or vomiting following a viral URTI
Bulging drum is painful which eases when the drum perforates and there is discharge
What organisms typically cause otitis media?
Pneumococcus and other streps ad staphs
What is the treatment for otitis media?
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
What are the types of chronic otitis media and what is the treatment?
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
What is a cholesteatoma? How is it treated?
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
What are the signs and treatment of mastoiditis?
Signs: fever, tenderenss and redness over mastoid, protruding pinna
Treatment is with antibiotics with mastoidectomy in more severe cases
What is a myringoplasty?
Repair of the tympanic membrane often from temporalis fascia, this allows a scaffold for the earfrum to grow onto
What are the clinical features of otitis media with effusion?
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.
What is the treatment of otitis media with effusion?
Usually 3 month period of observation followed by autoinflation of the eustation tube. If this does not work then consider grommets
What are the percentages for the causes of childhood hearing loss? genetic, non genetic and idiopathic?
50% genetic
25% non genetic
25% idiopathic
What are the newborn hearing screening tests?
otoacoustic emissions - tiny sounds preoduced by the outer hair cells as they amplify sounds
Audiological brainstem responses - electrodes pick up infant brain activity
How does a cochlear implant work?
By directly stimulating the auditory nerve in the cochlear
What are some of the causes of obstructive hearing loss in adults?
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
What are some of the causes of sensorineural hearing loss in adults?
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
What is the management of sudden sensorineural hearing loss in adults?
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
