Deafness and its rehabilitation Chunfu dai m,d ph. d
Deafness and its rehabilitation Chunfu Dai M.D & Ph.D
Background Speech frequency 500-3000Hz Normal hearing Sound conduction Sound perception( cochlea) Sound analysis(retro-cochlea) Deafmutism Profound hearing loss No language speech perception Language development quit(6M-6Y) Postlingual deafness deafness present following language developed
Background ◼ Speech frequency 500-3000Hz ◼ Normal hearing ◼ Sound conduction ◼ Sound perception (cochlea) ◼ Sound analysis (retro-cochlea) ◼ Deafmutism: ◼ Profound hearing loss. ◼ No language speech perception ◼ Language development quit (6M-6Y) ◼ Postlingual deafness ◼ deafness present following language developed
Morbidity 1/1000 in new born baby 1/100 in younger 14/100 in middle age 30/100 in 65-75 year old(presbycusis) 50/100 in >75 year old
Morbidity ◼ 1/1000 in new born baby ◼ 1/100 in younger ◼ 14/100 in middle age ◼ 30/100 in 65-75 year old (presbycusis) ◼ 50/100 in >75 year old
Classification Conductive deafness Sensorineural deafness Sensory deafness Lesion located in cochlea cochlear deafness) Nervous deafness a Lesion located in retrocochlear(retrocochlear deafness) Mixed deafness 1. Eardrum 5 Semcretear canals-B Vestibular nerve dal Nerve 4 SIDes
Classification ◼ Conductive deafness ◼ Sensorineural deafness ◼ Sensory deafness ◼ Lesion located in cochlea ( cochlear deafness) ◼ Nervous deafness ◼ Lesion located in retrocochlea (retrocochlea deafness) ◼ Mixed deafness
Classification Congenital deafness Hereditary deafness a Non hereditary deafness Acquired deafness Prelingual deafness Postlingual deafness
Classification ◼ Congenital deafness ◼ Hereditary deafness ◼ Non hereditary deafness ◼ Acquired deafness ◼ Prelingual deafness ◼ Postlingual deafness
Degree of hearing loss Based on PTA in 500, 1k, 2K HZ (WHO 1980 criteria) Mild HL(90 dB)
Degree of hearing loss ◼ Based on PTA in 500, 1k, 2k Hz (WHO 1980 criteria) ◼ Mild HL (90 dB)
Conductive hearing loss Pathogen Infection Trauma EAC Obstruction(foreign body, cerumen, tumor) Deformation ( aural atresia malformation of ossicular chain, dysplasia of oval or round window 1. Eardrum rcutar canals B Vestibular nerve Note Eustachian tube
Conductive hearing loss ◼ Pathogen ◼ Infection ◼ Trauma ◼ EAC Obstruction (foreign body, cerumen, tumor) ◼ Deformation (aural atresia, malformation of ossicular chain, dysplasia of oval or round window
Conductive hearing loss Location Deformation of auricle 3dB) s semicircular u Stenosis and autrsia of EAC(45- 60dB) Vestibula TM lesion(30-45 dB) Cochlea nerve Dysfunction of ossicular chain (50dB) Dysfunction of Eustachian tube (60dB) Lymphatic fluid dysfunction
Conductive hearing loss ◼ Location ◼ Deformation of auricle (3dB) ◼ Stenosis and autrsia of EAC (45- 60 dB) ◼ TM lesion (30-45 dB) ◼ Dysfunction of ossicular chain (50dB) ◼ Dysfunction of Eustachian tube (60dB) ◼ Lymphatic fluid dysfunction
Conductive hearing loss u Diagnosis u Tuning fork RI: negative WT: lesion side ST: prolongation ter fann 阳a33C1B0 PTA Bone threshold: normal o Air threshold 25-60 dB Image stud 00000n0一 0p00000009 100 110 10
Conductive hearing loss ◼ Diagnosis ◼ Tuning fork ◼ RT: negative ◼ WT: lesion side ◼ ST: prolongation ◼ PTA ◼ Bone threshold: normal ◼ Air threshold: 25-60 dB ◼ Image study
Conductive hearing loss Interventions Surgery(based on pathogen) Ventilation tube placement Malleus Incus Stapes myringoplasty Tympanoplasty Stapes surgery Hearing aid Tympanic Round Base of stapes membrane window in oval window
Conductive hearing loss ◼ Interventions ◼ Surgery (based on pathogen) ◼ Ventilation tube placement ◼ Myringoplasty ◼ Tympanoplasty ◼ Stapes surgery ◼ Hearing aid