Diagnosis Sensorineural hearing loss

1 diagnosis

1.1 case history
1.2 otoscopy
1.3 differential testing
1.4 tympanometry
1.5 audiometry
1.6 magnetic resonance imaging

diagnosis
case history

before examination, case history provides guidance context of hearing loss.

major concern
pregnancy , childbirth information
medical history
development history
family history

otoscopy

direct examination of external canal , tympanic membrane (ear drum) otoscope, medical device inserted ear canal uses light examine condition of external ear , tympanic membrane, , middle ear through semi-translucent membrane.

differential testing

differential testing useful when there unilateral hearing loss, , distinguishes conductive sensorineural loss. these conducted low frequency tuning fork, 512 hz, , contrast measures of air , bone conducted sound transmission.

weber test, in tuning fork touched midline of forehead, localizes normal ear in people unilateral sensorineural hearing loss.
rinne test, tests air conduction vs. bone conduction positive, because both bone , air conduction reduced equally.
less common bing , schwabach variants of rinne test.
absolute bone conduction (abc) test.

table 1. table comparing sensorineural conductive hearing loss

other, more complex, tests of auditory function required distinguish different types of hearing loss. bone conduction thresholds can differentiate sensorineural hearing loss conductive hearing loss. other tests, such oto-acoustic emissions, acoustic stapedial reflexes, speech audiometry , evoked response audiometry needed distinguish sensory, neural , auditory processing hearing impairments.

tympanometry

a tympanogram result of test tympanometer. tests function of middle ear , mobility of eardrum. can identify conductive hearing loss due disease of middle ear or eardrum other kinds of hearing loss including snhl.

audiometry

an audiogram result of hearing test. common type of hearing test pure tone audiometry (pta). charts thresholds of hearing sensitivity @ selection of standard frequencies between 250 , 8000 hz. there high frequency pure tone audiometry tests frequencies 8000-20,000 hz. pta can used differentiate between conductive hearing loss, sensorineural hearing loss , mixed hearing loss. hearing loss can described degree i.e. mild, moderate, severe or profound, or shape i.e. high frequency or sloping, low frequency or rising, notched, u-shaped or cookie-bite , peaked or flat.

there other kinds of audiometry designed test hearing acuity rather sensitivity (speech audiometry), or test auditory neural pathway transmission (evoked response audiometry).

magnetic resonance imaging

mri scans can used identify gross structural causes of hearing loss. used congenital hearing loss when changes shape of inner ear or nerve of hearing may diagnosis of cause of hearing loss. useful in cases tumour suspected or determine degree of damage in hearing loss caused bacterial infection or auto-immune disease. scanning of no value in age-related deafness.