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Hearing Impairment
Diagnostic Purposes and
Treatment in Practice
Prim. MUDr.Ivan Šejna, CSc
Introduction
Measure methods of hearing:
» Subjective
» Objective
Before testing:
- Otoscopy
- Mikrootoscopy
Goal and Result: Determine the Degree of
Hearing Loss and Nature of Diseases
(Pathology).
Contribute to better Treatment
Anatomy
Structure and Function of the Organ of Hearing
Conductive Part
= Conductive Hearing Loss
- External Ear
- Middle Ear – Tympanic Membrane Ossicles
- Liquid Filled Space
Perceptive Part
- Organ of Corti
- Auditory Nerve
- Hearing Pathway
- Cerebral Cortex
= Sensorineural Hearing Loss (H.L.)
= Cochlear H.L.
= Neural H.L.
= Supracochlear H.L.
= Central H.L.
Conductive + Sensorineural = Combined H.L.
Subjective Tests of Hearing
without Special Devices
• Whispering x Conversational Speech
• Tuning Force
• Weber´s
• Rinne´s
• Schwabach
• Gelle
(Obsolete ?)
Tests of Hearing Subjective
Hearing Thresholds
- Air Conduction Thresholds
- Bone Conduction Thresholds
Audiometer – Electronic Instrument Generate Pure Tone
Frequency 125 – 8000 Hz, Volume 0 – 110 dB and
Noise.
Performend in a Room Reasonably free of Noise
Type of Hearing:
- Conductive
- Sensorineural
- Mix
Medico-Legal Methods according Fowler – Sabin
Tests of Hearing Subjective
Speech Audiometry – Determined
Understanding Highly Usefful for
Diagnosis.
Special Words from CD
50 % Correctly understood Word =
Speech Receptual Thershold
100 % Correctly understanding Word =
100 % Speech Discrimination
Tests of Hearing Objective
• Impedance Measuremant
TYMPANOMETRY
• A Tympanogram = Normal Middle Ear and Eardrum
• B Tympanogram = Fluid in the Middle Ear
• C Underpressure in the Tympanic Cavity
• STAPEDIUS REFLEX Changes:
Present x Notpressent
Decay
Test of Hearing Objective
• ERA – Evoked Response Audiometry
• Registration Electrical Charges
Generated on Presentation of Sound
• in Cochlea ( Cochleography )
• In Brainstem ( BERA, BAEP )
• In Cortex ( CERA )
Test of Hearing Objective
OAE – Otoakustic Emission
The Ear, when stimulated can emit
Sound (prof.Kemp).
This Sound can be Measured when
Hearing is Normal
Usefful in Screening of Infants
(Newborns)
Therapy
• Cerumen:Preferency of Otomikroscopic
Menagement
• Sekretoric otitis:
– endoskopic adenotomy
– Transmyringing Drainege (Tubes)
Chronic Otitis, otosklerosis:
Otosurgery (Excelent Results )
Therapy
Sensorineural H.L.
Deafnes: Cochlear Implants
(Condition: Functional Auditory
Nerve)
Sudden Hearing Loss: Corticoids +
Vasoactive Drug Imidiately (in 24
hours)
Progressive Sensorineural H.L.:
Binaural Hearing Aids (Digital)
Presbyacusis
• Hearing Impaired Person (Seniors) =
Bad Communication:
• Central and Periferal
• Hearing Threshold
• Hearing Pathway
• Psychological
Difficulty Solutions (Therapy and
Rehabilitation)
Summary
Progres in Hearing Imparment: Testing + Treatment
G.P: Otoscopy
Whisper and Normal Speech
Tuning Fork
ENT:
Audiometry: Bone and Air Conduction Thresholds
Speech Audiometry
Objective Audiometry
Impedance Measurment (Tympanometry + Stapedius rfl.)
Evoked Potentials, OAE
Therapy: Digital Hearing Aids
Cochlear Implant