ototoxicity, otosclerosis and otitis media in hearing … · ototoxicity, otosclerosis and otitis...
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Ototoxicity, Otosclerosis and Otitis Media in Hearing aid Fitting
Kath Woolley M.Sc.North West School of Audiology
Definition of Ototoxicity
Damage to the ear- cochlea, auditory nerve or sometimes the vestibular system.
Drugs
Aminoglycosides e.g. Gentamycin ‘Mycin’
Loop Diuretics e.g. Furosemide
Chemotherapy Agents e.g. CisplatinPlatinum based
Adverse Effect of Aminoglycosides
Damage to the vestibular system Headache Ear fullness Imbalance Inability to tolerate head movement Problems walking in dark
Acute Cochlear Damage
Tinnitus > 4000 Hz Low frequencies affected later Profound? Loss usually permanent
Ototoxicity Process Poorly understood
Kanamycin, Neomycin, Amikacin toxic to the cochlea
Free Radical
The Risk of Noise and Chemicals Together
Noise alone- Risk factor 4.1
Solvent mixture alone- Risk factor 5.0
Noise and Toluene- Risk factor 10 to 27.5
Variables in Ototoxicity
Bilateral, symmetrical, asymmetrical Time of onset Single dose. After completion of course. Monitor hearing for 6 months after. Benefits vs. risks Mouth vs. injection Susceptible Genetic link
Prevention of Ototoxicity Aminoglycoside, loop diuretics,
chemotherapy, aspirin, quinine – infusion rates, monitor drug levels, kidney history & hearing
Daily administration Lowest effective dose Other ototoxic agents High risk- alternatives Avoid noise for 6 months
General Monitoring High frequencies affected first- high
frequency audiometry No tinnitus monitoring Dizziness Handicap Inventory
Ototoxicity and Hearing Aid Fitting
Recruitment Tinnitus
Frequency selectivity reducedSpeech in noise unclearDead regions
Consider hearing aid output
What is Otosclerosis?
A disorder affecting collagen Cause? Remodelling faulty Oval window/round window Sensory, neural, mixed Gradual Progressive
Incidence Hereditary in 70% cases Dominant gene Virus? Unilateral 10-15% Caucasians Present in 10% of pop. Age of onset – approx. 30 years Females Worse in pregnancy
Symptoms & Diagnosis
Progressive conductive hearing loss
Carhart’s notch @ 2 kHz
Tinnitus in 4/5
Paracusis Willisi
Symptoms & DiagnosisSchwartze’s sign
Dizziness in 1/ 4 Weber lateralised to
affected ear Sometimes bluish cast
over eye whites Difficulty hearing when
chewing?
Risk Factors & Treatment
More common in White & Asian
Women Age-15 – 35 years +ve family history Drinking non-
fluoridated water-very controversial
Hearing aids BAHA Surgery Fenestration Stapedectomy Stapedotomy Fluoride therapy Oestrogen blockers Biphosphonates
Possible Complications of Surgery
Loss of hearing in 1 in 100
Dizziness
Taste disturbance
Reaction to ear dressings
Tinnitus
Considerations of Otosclerosis and Hearing Aid Fitting Type of hearing loss Conductive = more gain REM’s and conductive- careful
interpretation NAL- not for conductive losses BSA Guidance on REM’s (2007) Progressive- increase amplification
Otitis Media Eustachian tube
Otitis Media- inflammation of the middle ear
Eustachian tube dysfunctionair in middle ear absorbed-ve mepexudate fills up middle ear
Acute (Suppurative) Otitis Media
Acute – rapid onset following a short but severe course
Suppurative- formation of pus or discharge
Inflammation of mucous membrane lining middle ear cleft
Bacteria Responsible
Adenovirus Rhinovirus Pneumococcus Haemophilus Influenzae Streptococcus Staphylococcus
Symptoms
Pain Temperature Earache Pressure build up Perforation Discharge containing pus escapes Antibiotics
Risk Factors Age Adenoids Frequent URTI Prematurity Craniofacial abnormalities Nurseries Poor socio-economic conditions Cold weather Pre-existing middle ear effusion
Chronic Suppurative Otitis Media
Chronic- long-standing Suppurative – formation of pus or
discharge Acute infection Irritation of lining of
middle earinfection
destroys bone Infectiongranulation
Bacteria responsible
Pseudomonas aeroginosa Staphylococcus aureaus Proteus species Klebsiella pneumonia Diptheroids
Symptoms: hearing loss; fever; vertigo; pain
‘Safe’Ear and ‘Unsafe Ear’
Perforation in pars tensa
No local destruction
Perforation in attic region (pars flaccida)
Infection of attic, antrum, mastoid
Possible cholesteatoma
Cholesteatoma Looks like an onion Produces osteolytic enzymes Complications include: Hearing loss Vertigo Headaches Facial nerve palsy Meningitis Epidural abscess
Otitis Media with Effusion Effusion-seeping of watery fluid from
tissue OME is thick or watery fluid in middle ear
with NO infection No pain No fever
Unilateral fluid in an Adult requires further investigation
Considerations of Otitis Media and Hearing Aid Fitting No active infection Conductive hearing loss and fluctuating Follow up fine tuning appointments Rigidity of TM and presence of fluid
increase the risk of feedback