residual inhibition - ENT

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residual inhibition - ENT

CLINICAL ASSESSMENT OF TINNITUS

AN AUDIOLOGICAL APPROACH

Prof. Dr. B. Vinck

University of Ghent, Belgium

University of Pretoria, South-Africa


Introduction

“I'm going to bring such a disaster

on this place that the ears of

everyone who hears about it will

ring”

Jeremia 19:3


Clinical Measurement of Tinnitus


Clinical measurement of Tinnitus

It is important to measure tinnitus in order to obtain a status before

the start of any treatment.

Without that status it is difficult to show that different treatments really changed

anything

It is important to measure tinnitus in order to gain more insight

about the nature of the problem.

It is important to measure tinnitus in order to provide reassurance

to the patient that today “the doctor believes him/her” and “that

his/her tinnitus is real” (important too for family members)

Medicolegal aspects …..


CIBA Foundation Symposium (‘85)

TINNITUS PITCH

TINNITUS LOUDNESS

MASKABILITY

RESIDUAL INHIBITION

To allow comparison between different clinics


PURE TONE AUDIOMETRY FIRST !!!

(If loudness intolerance mentioned : LDL)

Advanced Clinical Audiometer

HF – 2 SEPARATED CHANNELS

HIGH FREQ RESOLUTION …. e.g. Interacoustics AC 40


125 Hz – 16000 Hz

e.g. SENNHEISER HEADPHONES

HIGH FREQUENCY AUDIOMETRY


TINNITUS and HIGH FREQUENCY

AUDIOMETRY

Shim et al, 2009

12/18 tinnitus patients elevated high

frequency thresholds between 10-16 kHz

compared to control group

ALSO VERY IMPORTANT FOR ASSESSMENT TINNITUS PITCH !!!


HISTORY : TONAL VERSUS NOISE LIKE

TINNITUS

DESCRIPTION OF TYPES OF TINNITUS

RINGING

CRICKETS

HIGH-PITCHED TONE

HISSING

HUMMING

ROARING

BUZZING

CLICKING

PULSING

RUNNING WATER

STATIC NOISE

SIREN

CRACKLING

FIZZING

James Hall (2007)


HISTORY : TONAL VERSUS NOISE LIKE

TINNITUS

REDUCE DESCRIPTION TO TWO CATEGORIES

NOISE TONE


HISTORY : TONAL VERSUS NOISE LIKE

TINNITUS

TINNITUS CLINIC UNIVERSITY HOSPITAL

GHENT (SINCE 1998 : n = 22368 patients)

GHENT


31%

5%

IMPORTANT FOR PITCH MATCHING

TYPE OF TINNITUS

64%

n = 22368

patients

Tone

Noise

?

TINNITUS POPULATION UGENT

(1998- 2010)


HISTORY : LOCALISATION OF TINNITUS

UNILATERAL OR BILATERAL ??

20%

10%

34%

LOCALISATION

BE CAREFUL : STENGER EFFECT !!!

36%

UNI LEFT

UNI RIGHT

BILATERAL

HEAD

n = 22368 patients

TINNITUS POPULATION UGENT

(1998- 2010)


4 kHz

Unilateral

Tinnitus

RIGHT !!!!

STENGER

PHENOMENON

4 kHz


TINNITUS PITCH

TINNITUS LOUDNESS

MASKABILITY

RESIDUAL INHIBITION


1. ASSESSMENT TINNITUS PITCH

I. Identify “Tinnitus Ear” and

“Stimulus Ear”

II. Ear with most bothersome

tinnitus is “Tinnitus ear” and

contralateral ear is “Stimulus

ear”

Remark (1)

In case of binaural diplacousis : ipsilateral

matching is indicated !

Remark (2)

Be sure the patient understands the

different between pitch and loudness


Procedure

ASSESSMENT TINNITUS PITCH

TWO ALTERNATIVE FORCED CHOICED METHOD

Two tones are presented alternately to the patient (several

times) and patient indicates which tone (noise) is more like the

tinnitus

The order of presenting the pair of tones (noises) must be

varied at random !


TWO PHASES

ASSESSMENT TINNITUS PITCH

PROVISIONAL PITCH MATCH

OCTAVE CONFUSION TEST


EXAMPLE

PROVISIONAL PITCH MATCH

* PROVISIONAL MATCH = 5000 Hz

1000 Hz 2000 Hz 2000 Hz

2000 Hz 3000 Hz 3000 Hz

4000 Hz 5000 Hz 5000 Hz

5000 Hz 6000 Hz 5000 Hz

*


OCTAVE CONFUSION TEST

* BEST MATCH = 5000 Hz

1000 Hz 2000 Hz 2000 Hz

2000 Hz 3000 Hz 3000 Hz

4000 Hz 5000 Hz 5000 Hz

5000 Hz 6000 Hz 5000 Hz

5000 Hz 10000 Hz 5000 Hz

*


80% > 2000 Hz !!!

Percentage (%) (n= 22368)

25

20

15

10

5

0

8

< 1000

Hz

PITCH MATCHING

12

1 kHz - 2

kHz

2 kHz -

4kHz

Prevalence

21

19,8

4 kHz - 6

kHz

TINNITUS POPULATION UGENT

(1998- 2010)

18,3

6 kHz - 8

kHz

14,2

8 kHz -

10 kHz

6,7

10 kHz -

16 kHz

ANNOYANCE FOR HIGH PITCHED SOUNDS > LOW PITCHED SOUNDS ! IMPORTANT

FOR TREATMENT (PITCH REDUCTION)


TINNITUS PITCH

TINNITUS LOUDNESS

MASKABILITY

RESIDUAL INHIBITION


2. ASSESSMENT LOUDNESS

I. Often tinnitus loudness is

reported in dB sensation level

I. dB SL represents the intensity,

NOT loudness, of the signal

above threshold

I. Problem :

At frequencies with normal

hearing the match in dB SL can be

much greater than at

frequencies with hearing loss

(Recruitment !!!)


2. ASSESSMENT LOUDNESS

Some prefer to report loudness in

SONES

ADVANTAGE :

• MORE MEANINGFULL

e.g. Loudness of 4 sones =

tone : 60 dB SPL at 1 kHz

• EASIER TO COMPARE PATIENTS


FLETCHER MUNSON CURVE


2. ASSESSMENT LOUDNESS

Figuur Tyler pagina 158 inscannen

L sones = k(P − P 0 ) 6

P = Intensity of matched sound (in Pa)

P 0 = Intensity of auditory threshold


2. ASSESSMENT LOUDNESS

MOST CLINICS STILL MEASURE IN

dB SL


2. ASSESSMENT LOUDNESS

REPORT LOUDNESS IN dB SL

AT PITCH TINNITUS AT FREQ = 1 KHz

Recommended !


Percentage (%) (n= 22368)

40

35

30

25

20

15

10

5

0

38,4

LOUDNESS MATCHING

21

15,2

12

0 - 2 2 - 4 4 - 6 6 - 8 8 - 10 10 - 15 15 - 20 > 20

6,4

dB (Sensation Level)

IMPORTANT TO USE THIS FACT IN COUNSELING THE PATIENT

TINNITUS POPULATION UGENT

(1998- 2010)

70 % < 6 dB SL) !!!!

5

2 1


TINNITUS PITCH

TINNITUS LOUDNESS

MASKABILITY

RESIDUAL INHIBITION


3. EVALUATION MASKABILITY

I. DETERMINE THE LOWEST

LEVEL OF NBN OR BBN or

TONE TO MAKE A PATIENT’S

TINNITUS INAUDIBLE (i.e.

Masking the tinnitus)

II. This level is called the

Minimum Masking Level

(MML)


3. EVALUATION MASKABILITY

Examples :

FELDMANN MASKING

CURVES

TYLER CLASSIFICATION

SYSTEM


Feldmann Masking Curves

TECHNIQUE

Continuous tone or

noise band (1-2 sec)

250, 500, 1 K, 2K, 3K,

4K, 6K en 8 kHz

Classification (Type I-V)

1 st NBN, if not maskable then

pure tone stimulation

Unilateral : ipsilateral &

contralateral masking curve

Bilateral tinnitus : ipsilateral

Masking curve of each ear

separately

Conclusions


High pitched tonal tinnitus

Type I. Convergence

Type III. Congruence

White noise tinnitus

Low pitched humming sound

Type II. Divergence

AC threshold

Masking level


≥ 20 dB

White noise

Type IVa. Distance

Type V. Persistent

Tones > Noise

Pulsatile hissing sound

Type IVb. Dispersion

No maskability


Feldmann Masking Curves

12%

20%

33%

35%

Convergence

Congruence

Distance

Other


Feldmann Masking Curves

INTERPRETATION

Types I-III : Good candidate acoustical masking

Types II-IV : Bad candidate acoustical

masking/good candidate electrostimulation

Type V : Bad candidate acoustical masking


Feldmann Masking Curves

Interpretation

Relationship to pathology

Type I Noise induced hearing loss

Type II Unknown etiology – normal hearing

Type III Meniere’s disease

Type Iva Presbycusis

Type Iv Secretory otitis media

Type V Cochlear degeneration


3. EVALUATION MASKABILITY

Examples :

FELDMANN MASKING

CURVES

TYLER CLASSIFICATION

SYSTEM


Tyler classification system

Figuur Tyler pagina 163 inscannen


TINNITUS PITCH

TINNITUS LOUDNESS

MASKABILITY

RESIDUAL INHIBITION


Concept

Residual inhibition

Feldmann (1971) observed that a substantial

proportion of tinnitus patients experienced a brief

reduction of their tinnitus after cessation of the masker

This phenomenon is known as “RESIDUAL INHIBITION”

(also referred to as “residual suppression”


Residual inhibition : mechanism


Residual inhibition : mechanism

TEMPORAL MASKING


Residual inhibition : procedure

DETERMINE MINIMUM MASKING LEVEL (

MML)

APPLY MASKING NOISE AT MML + 10 dB FOR

60 SECONDS

OBSERVE DEGREE OF RESIDUAL INHIBITION

IMPORTANT : WARN THE PATIENT IT IS A TEST – NOT A

TREATMENT !!!!!


Residual inhibition : results


Rebound

Negative

Partial

Complete

Residual inhibition : clinic

9

11,8

37,8

41,4

0 10 20 30 40 50


Residual inhibition : procedure

DETERMINE MINIMUM MASKING LEVEL (

MML)

APPLY MASKING NOISE AT MML + 10 dB FOR

60 SECONDS

OBSERVE DEGREE OF RESIDUAL INHIBITION

REGISTER DURATION OF RESIDUAL INHIBITION


70

60

50

40

30

20

10

0

Residual inhibition : procedure

63,4

21,2

7,4

5,2

2,8

0-2 Min 2-5 Min 5-7 Min 7-10 Min > 10 Min


Other tests …

Otoacoustic Emissions ABR


Otoacoustic Emissions in the

assessment of tinnitus


Literature

Otoacoustic Emissions in the

assessment of tinnitus

Granjeiro et al. Transient and distortion product evoked oto- acoustic emissions

in normal hearing patients with and without tinnitus. Arch Otorhinolaryngol

Head Neck Surg 134: 2008.

Tinnitus group versus control group

Results :

TEOAES

70% abnormal in Tinnitus group

16% abnormal in Control group

DPOAES

68% abnormal in Tinnitus group

50% abnormal in Control group


Literature

ABR and Tinnitus

Kehrle et al. Comparison of auditory brainstem response results

in normal hearing patients with and without tinnitus. Arch

Otorhinolaryngol Head Neck Surg 134: 2008

Tinnitus group versus control group

Results :

ABNORMAL ABR IN 43 % OF TINNITUS GROUP

SIGNIFICANT INCREASE IN WAVE I-III INTERVAL


EXTRA IN CASE OF HYPERACUSIS


HYPERACUSIS


SCHULTZ et al (1987)

TOLERANCE


TOLERANCE

Decrease in tolerance

Loudness discomfort levels < 90 dB HL in two

or more frequencies (Goldstein, 1996)

Loudness discomfort levels < 100 dB HL in two

or more frequencies (Jastreboff, 2000)

Reduced dynamic range (55-60 dB HL)


TERMINOLOGY

USE OF TERMS FOR SENSITIVITY

ALLODYNIA

Abnormal auditory aversions to normal daily sounds

HYPERACUSIS

Hyperacute hearing thresholds

ODYNACUSIS

Lower ULL (typically 86-98 dB HL)

PHONOPHOBIA

Fear potentiated aversion


HYPERACUSIS MECHANISM

Herraiz, 2008


HYPERACUSIS MECHANISM


HYPERACUSIS DIAGNOSIS

AUDIOLOGICAL TESTING

LOUDNESS DISCOMFORT LEVELS (LDL)

Pure tones

Ascending technique

Continuous, not pulsed

Perform it twice !!!

Patients can stop the

test


Results

HYPERACUSIS DIAGNOSIS


Johnson Hyperacousic Dynamic Range

Quotient

HYPERACUSIS DIAGNOSIS

TOOL TO POTENTIALLY QUANTIFY HYPERACUSIS

QUANTIFY PROGRESS WITH HYPERACUSIS TREATMENT


Johnson Hyperacousic Dynamic Range

Quotient

HYPERACUSIS DIAGNOSIS

Johnson, 1999


HYPERACUSIS and OAE/ABR

ABNORMAL DP GROWTH

FUNCTIONS

Efferent suppression

(Collet effect)

ABR : UNCLEAR ????


HYPERACUSIS DIAGNOSIS

Other audiological parameters

Acoustic reflex testing (ART) & Tymp

Tensor tympani syndrome

94% OF HYPERACUSIS PATIENTS

Often misdiagnosed as Meniere


Other audiological parameters

CERA

LOUDNESS SCALING


HYPERACUSIS DIAGNOSIS


SUMMARY AND CONCLUSIONS

CLINICAL MEASUREMENT IS IMPORTANT TO BOTH PATIENT

AND AUDIOLOGIST

PSYCHOLOGICAL IMPACT

TRY NOT TO REDUCE YOUR CONSULTATION TO A

TECHNICAL SESSION : TALKING IS IMPORTANT

DO NOT SKIP THE HISTORY !!! MOST IMPORTANT ASPECT

OF ANY TINNITUS APPROACH


Baie dankie

Ngiyabonga

Enkosi

Ndi a livhuha

Asante sana

…..

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