Contents
Introduction
Hearing loss can be:
- Sensorineural
- Conductive
- Mixed
Hearing loss is quantified by audiological assessment and the production of an audiogram which quotes air and bone hearing thresholds in dB.
Sensorineural hearing loss
- pathology in cochlear or CN VIII
- commonly due to irreversible loss of hair cells on organ of Corti
- Permanent hearing loss
- Audiometry; loss in the high frequencies
Conductive hearing loss
- pathology in outer or middle ear
- Commonly responds to surgery
Comparison
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Cause
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Conductive hearing loss
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Sensorineural hearing loss
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Congenital
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Abnormalities of ossicles
Atresia
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Genetic
Congenital rubella
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Acquired
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Otitis externa
Wax
Foreign body
Middle ear effusion
Cholesteatoma
Perforation
otosclerosis
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Perinatal hypoxic injury
Perinatal jaundice
Trauma; injury, surgery, noise exposure
Chronic otitis media
Measles
Syphilis
Ototoxic drugs; aminoglycacides and cytotoxics
Acoustic neuroma
Meniere’s disease
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History Taking
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Taking a general hearing loss Hx
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Taking a paediatric hearing loss Hx
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