The First Objective Audiometer (Wedenberg) Cow Bell The First Objective Audiometer (Wedenberg)

Subjective Component The patient

Subjective Component The Operator

Sound STR Tympanometry OAE ECoG 5ms BERA 10ms CERA 500ms CNV ERA S U B J E C T I V E A U D I O M E T R Y Sound STR OUTER & MIDDLE EAR INNER EAR BRAIN STEM CORTEX CEREB- RUM Tympanometry OAE ECoG 5ms BERA 10ms CERA 500ms CNV ERA

Hang STR Tympanometria OAE ECoG BERA CERA CNV ERA S Z U B J E K T Í V A U D I O M E T R I A Hang STR KÜLSŐ és KÖZÉP FÜL BELSŐ FÜL AGY- TÖRZS CORTEX CEREB- RUM Tympanometria OAE ECoG BERA CERA CNV ERA

Hang STR Tympanometria OAE ECoG BERA CERA CNV ERA S Z U B J E K T Í V A U D I O M E T R I A Hang STR KÜLSŐ és KÖZÉP FÜL BELSŐ FÜL AGY- TÖRZS CORTEX CEREB- RUM Tympanometria OAE ECoG BERA CERA CNV ERA

Hang STR Tympanometria OAE ECoG BERA CERA CNV ERA S Z U B J E K T Í V A U D I O M E T R I A Hang STR KÜLSŐ és KÖZÉP FÜL BELSŐ FÜL AGY- TÖRZS CORTEX CEREB- RUM Tympanometria OAE ECoG BERA CERA CNV ERA

Hang STR Tympanometria OAE ECoG BERA CERA CNV ERA S Z U B J E K T Í V A U D I O M E T R I A Hang STR KÜLSŐ és KÖZÉP FÜL BELSŐ FÜL AGY- TÖRZS CORTEX CEREB- RUM Tympanometria OAE ECoG BERA CERA CNV ERA

Hang STR Tympanometria OAE ECoG BERA CERA CNV ERA S Z U B J E K T Í V A U D I O M E T R I A Hang STR KÜLSŐ és KÖZÉP FÜL BELSŐ FÜL AGY- TÖRZS CORTEX CEREB- RUM Tympanometria OAE ECoG BERA CERA CNV ERA

Objectiv audiometry Evoked Responses Reflexes STR Acoustic response OAE Electric Response Audiometry: ERA ECoG 5 ms BERA 10 ms MLR 50 ms Steadystate response CERA 250-500 ms CNV ca. 2 sec

Age-dependence in examinations Type of examination 0 1 2 3 4 5 6 ERA, OAE Stapedial reflex Reflexaudiometry Behaviour-audiometry Play-audiometry Pure-tone audiometry Speech-audiometry Supratreshold-audiometry

Tympanometry, STR, MFT Tympanograms A-type B-type C-type Loudspeaker Tone-generator A-type Airpump Equalizer Ampli-fier Voltmeter Earcanal-Probe Amplifier Microphon Voltage Controller Tympanometry, STR, MFT B-type C-type Normal Reflexdecay

Loudspeaker Amplifier Tone-generator Air-pump Amplifier Equaliser Voltmeter Ear-canal-Probe Microphone Voltage Controller

Pressure [dPa] Pressure [dPa] Pressure [dPa] Type A Type B Type C

Normal STR-decay Pathological STR-decay

Hearing Pathway

Photosummation

Digitalis purpurea Finger Hut Fox glove Gyüszűvirág

A/D Conversion AVERAGING AVERAGING 2048 sample Channels Analog signal AVERAGING 2048 sample averaging Digital data

Minták száma Sampling Rate Mintavétel sűrűsége Number of Sampling sample Sampling Rate 85 points 51 points 256 points Mintavétel sűrűsége Number of Sampling

Sound stimuli Sound stimuli Click01 click10 click23 One-cycle Sinus Halve-cycle Sinus rectangular biphase Click01 click10 click23 Sound stimuli Sound stimuli STOP Sinus tone without modulatio 500 4000 risetime = 0 Wavolvaso Rising Plateau decreasing T.burst05 t.burst4 -> longer Ms/division

Built in the computer Sound generator Ampli- fier Monitor/ Printer AD-Conv Averager Ampli- fier Pre Amplifier

ECoG

Tchaikovsky B minor piano concerto Panpipe

Amplifier Loudspeaker Tape recorder

0.day Neomycin 4.day Neomycin 9.day Hearing aid

SP less than half as AP is normal SP more than half as AP is recruitment

Advantages of ECoG: Exact information about the periphery No negative interaction of the general anesthesia Disadvantages of ECoG: Information is only about the periphery Invasive

BERA (ABR)

Intenzity-latency gram BERA-thresholds

Retrocochlear lesion I –V IPL 4.2 +/- 0.3 <4.5 normal >4.5<4.65 suspect >4.6 RL Retrocochlear lesion

Waves are successive missing Retrocochlear lesion

Recruitment

Advantages of BERA : Exact information from the periphery No negative interaction of the general anesthesia Noninvasive Brainstem topo-diagnostic Precise objective hearing threshold (2-4 kHz) Drawbacks of BERA: Information is only from the periphery There is no frequency-specificity

BERA

MLR-Threshold MLR FFR BERA

MLR BERA

40 Hz Response

Advantages of MLR : Noninvasive Frequency -specificity Drawbacks of MLR: Slight interaction of general anesthesia Threshold is not precise Time consuming

CERA 500 ms

Advantages of CERA: Noninvasive Frequency -specificity Drawbacks of CERA: Strong interaction of general anesthesia Threshold is not precise Time consuming

CNV MMN

ON-Responses all together

BeforeTreat-ment After Treat-ment SUDDEN DEAFNESS BeforeTreat-ment After Treat-ment AUDIOGRAM BERA DPOAE TEOAE

OAE + BERA TUMOUR

STEADY-STATE POTENCIALS AMFR MASTER John&Picton1998 Steady-St. Resp

David Kemp 1978

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