Types of Hearing LossTypes of Hearing Loss

Heidi Walsh 2010Heidi Walsh 2010

Conductive Hearing LossConductive Hearing Loss

Part of ear affectedPart of ear affected: outer and/or middle: outer and/or middle

DescriptionDescription: occurs when sound cannot : occurs when sound cannot reach inner ear – in other words when reach inner ear – in other words when something prevents sound from getting something prevents sound from getting into ear into ear

Outer Ear - CausesOuter Ear - Causes

Blocked ear canalBlocked ear canalWaxWax Infection / swellingInfection / swelling

Perforated eardrumPerforated eardrumScarred / thickened Scarred / thickened

eardrumeardrumOften caused by glue Often caused by glue

earear

Middle Ear - CausesMiddle Ear - Causes

Broken ossiclesBroken ossiclesHammer, anvil, stirrupHammer, anvil, stirrup

Glue earGlue ear Infection with build up Infection with build up

of sticky fluid which of sticky fluid which prevents ossicles from prevents ossicles from vibrating properlyvibrating properly

Middle Ear - CausesMiddle Ear - Causes

Eustachian tube not Eustachian tube not opening and closing opening and closing properlyproperlyCold or catarrhCold or catarrhAllergic reactionAllergic reaction

Middle Ear - CausesMiddle Ear - Causes

OtosclerosisOtosclerosis Bony growth around Bony growth around

base of stirrup which base of stirrup which stops it from moving stops it from moving properlyproperly

Tends to run in familiesTends to run in families Often triggered by Often triggered by

pregnancy in womenpregnancy in women

Sensori-neural Hearing LossSensori-neural Hearing LossPart of ear affectedPart of ear affected: inner ear and/or : inner ear and/or

auditory nerveauditory nerve80% of people with a hearing loss have SNHL80% of people with a hearing loss have SNHL

DescriptionDescription: occurs when either the hair : occurs when either the hair cells in the cochlea and/or the nerve to the cells in the cochlea and/or the nerve to the brain are damaged and sound is not been brain are damaged and sound is not been passed onto the auditory centre in the passed onto the auditory centre in the brainbrain

Very rare that the exact cause can be Very rare that the exact cause can be identifiedidentified

The Inner EarThe Inner Ear

Cochlea

Auditory nerve

Inner Ear - CausesInner Ear - Causes

Commonest cause – old age deafness Commonest cause – old age deafness (presbyacusis)(presbyacusis)

Noise damageNoise damageVirus or infectionVirus or infectionHigh doses of some medicationsHigh doses of some medicationsChemotherapy / radiotherapy – sometimes Chemotherapy / radiotherapy – sometimes

Inner Ear - CausesInner Ear - Causes

Acoustic neuroma (benign tumour)Acoustic neuroma (benign tumour)Accident – head injuryAccident – head injuryAutoimmune Inner Ear Disease (AIED)Autoimmune Inner Ear Disease (AIED)Meniere’s DiseaseMeniere’s DiseaseCongenital Congenital

Mixed Hearing LossMixed Hearing Loss

Part of ear affectedPart of ear affected: Outer/middle and : Outer/middle and innerinner

DescriptionDescription: combination of both types of : combination of both types of hearing loss described previouslyhearing loss described previously

CausesCauses: generally more than one cause – : generally more than one cause – or conductive loss plus age-related or conductive loss plus age-related hearing loss hearing loss

Central Auditory Processing Central Auditory Processing Disorder (CAPD)Disorder (CAPD)

Part of ear affectedPart of ear affected: none: noneCaused by a difficulty in the hearing part of Caused by a difficulty in the hearing part of

the brainthe brainDescriptionDescription: occurs when sound reaches : occurs when sound reaches

brain but there is a delay / difficulty in brain but there is a delay / difficulty in identifying sound patternsidentifying sound patternsa sort of hearing dyslexiaa sort of hearing dyslexiacan be helped by lipreading as ability to can be helped by lipreading as ability to

process words is not affectedprocess words is not affected

More InformationMore Information

RNID websiteRNID websitehttp://www.rnid.org.uk/information_resourchttp://www.rnid.org.uk/information_resourc

es/aboutdeafness/es/aboutdeafness/ Includes factsheets & videosIncludes factsheets & videos