4. Routine clinical tests of hearing

Routine clinical tests of hearing

1. Routine Clinical
Tests of Hearing
Dr. Krishna Koirala

2. •Assessment of Hearing is an integral part of ENT
examination
•Hearing tests can be divided into subjective and
objective tests
•Subjective tests like finger friction test , watch test
and voice test (whisper/conversation/ loud voice)
lack standardization and have become obsolete
•Although subjective, tuning fork tests are considered
standard tests of hearing evaluation in current clinical
practice

3. Aims of Clinical tests of Hearing
•Estimation of hearing threshold
•Confirm Hearing Loss
•Differentiate type of Hearing Loss (Conductive /
Sensorineural )
•Identification of non-organic hearing loss
(Malingerers)

4. Tuning Forks (Gardiner Brown)

5. Different Tuning Fork frequencies used
in ENT
•256, 512, 1024 Hz
•128 Hz produces more vibration sense
•>1024 Hzshort tone decay time

6. •512 Hz Tuning Fork is ideal in ENT
•No false vibration sensation
•Optimum tone decay time
•Lies in speech frequency range

7. Striking Surfaces
•Hard:Olecranon, radial styloid process, patella
•Soft:Thenar & hypothenar eminences,
•Thick rubber pad
•Tuning fork is allowed to fall by its own weight
•Impact area is between proximal two-thirds &
distal one-thirds of its prongs

9. Tuning fork Tests
•RoutineTests
•Rinne test
•Weber test
•Pomroy’s test (ABC )
•Schwabach’s test
•Others
•Bing test
•Gelle’s test
•Stenger’s test
•Chimani Moo’s test

10. Rinne Test
1) Duration comparison technique
Vibratingtuningforkplacedonpt'smastoidPatient
signalswhensoundceases→Movevibratingtuningfork
overopeningofearcanal(2cmaway&axisparallelto
it)→Patientindicatesifsoundisstillheard

11. 2) Loudness comparison technique
Vibrating tuning fork placed on pt's mastoid
Pt signals if sound is heard→ Move vibrating
tuning fork immediately over opening of ear
canal→ If sound is heard→ patient asked to
tell which sound is louder?

12. Rinne Test

14. Results of Rinne Test
•A.C. > B.C. (positive test)
•Normal hearing or Sensorineural deafness
•B.C. > A.C. (negative test)
•Conductive deafness

15. Rinne Negative with different
frequency Tuning forks
•256 Hz15 -30 dB HL (Mild conductive Loss)
•512 Hz31 -45 dB HL ( Moderate conductive Loss)
•1024 Hz46 -60 dB HL (Severe conductive Loss)

16. Weber Test
Procedure:
Vibrating 256/ 512 Hz
tuning fork placed in
midline of pt’s skullat
forehead / vertex /
central incisor

17. Results of Weber test
•Sound heard equally (central) : Normal hearing or B/L
equal deafness
•Sound lateralizes to deafer ear : Conductive deafness
•Sound lateralizes to better hearing ear : Sensorineural
deafness

18. Why does Weber lateralize to deafer ear in
Conductive Hearing Loss ?
1.Lackofmaskingeffectofsurroundingnoiseon
tuningforksound,asairconductionisreducedin
conductivedeafness
2.Lackofdispersionofsoundenergyduetoossicular
break

19. Absolute Bone Conduction Test (ABC)
•Pt's B.C. is compared with normal examiner's B.C.
•Vibrating tuning fork placed on pt's mastoid with pt’s
E.A.C. occluded(to prevent A.C.)→ pt signals when
sound ceases→ vibrating tuning fork placed on
examiner's mastoid with examiner'sE.A.C. occluded

21. Results of Absolute Bone Conduction Test
•Pt stops hearing before examiner : Sensorineural
deafness
•Both hear for same duration : Normal hearing /
conductive deafness

22. Schwabach's Test
•Same as A.B.C. but E.A.C. is not occluded
•Pt stops hearing before examiner
•Sensorineural deafness
•Both hear for same duration
•Normal hearing
•Pt hears longer than examiner
•Conductive deafness

23. Schwabach Test

24. False Negative Rinne
•Etiology:Unilateralsevere/profoundsensorineural
deafness
•Detection:Rinnenegative(Noresponsenearthe
canal),Weberlateralizedtobetterhearingear
•Confirmation:A.B.C.reducedindeafear
•Correction:RepeatRinnetestwithmaskingofbetter
earwithBarany'snoisebox

25. Mechanism of false negative Rinne
In deaf ear, air conduction & bone conduction are
absent.Trans -cranial transmission of sound to
opposite cochleais perceived as ipsilateral bone
conduction. Reported as bone conduction > air
conduction in deaf ear (Rinne Negative)

26. Gelle Test
•Vibrating tuning fork placed on pt's mastoid &
examiner increases pt's E.A.C. pressure with
Siegel's speculum
•Softer sound
•Normal hearing or Sensorineural deafness
•No change in sound
•Conductive deafness

27. Bing Test
•Vibrating tuning fork placed on pt's mastoid &
examiner blocks pt's E.A.C.
•Louder sound: normal hearing or Sensorineural
deafness
•No change in sound:conductive deafness