This increase in pressure in ear canal pushes the tympanic membrane and ossicles inward, leading to rise in intralabyrinthine pressure. Gelle’s test: Tuning fork is placed on mastoid and the pressure in the ear canal is increased using the Siegle’s speculum. Positive bing test (Louder when occluded): Normal or SNHLī.Bing test: This is like ABC test, but the external ear canal is alternately closed and opened by pressing and releasing the tragus. If the clinician doesn’t listen the sound after transferring it from mastoid of the patient, the procedure may be reversed.Ĭlinician listens equal to that of patientĪ.Clinician listens whether he can appreciate the sound stimulus or not.Immediately same fork is transferred over mastoid bone of the clinician and simultaneously ear canal is closed by pressing the tragus.Foot piece of vibrating tuning fork is kept over mastoid bone and patient listens to the fork till sound disappears completely.Examiner closes the test ear by gently pressing the tragus against ear canal.Pre-requisite: Clinician should have normal bone conduction level or at least he should know his bone conduction level. It includes occlusion of the External Auditory Canal by pressing the tragus to reduce the ambient sound in the surrounding, which is not done in Schwabach’s test. Principle: This is a modified Schwabach’s test where, the bone conduction level of patient is compared to that of the clinician. Note: Weber is a sensitive test and a difference of even 5 dB is sufficient to lateralise the Weber. Ask the patient – which ear hears the sound louder?.Place the foot piece or base of the vibrating tuning fork on either of midline of vertex, forehead, chin or upper incisor teeth.This is because the conduction problem masks the ambient noise of the room, whilst the well-functioning inner ear picks the sound up via the bones of the skull causing it to be perceived as a louder sound than in the unaffected ear. Principle: This test is useful in identifying unilateral hearing loss. A patient with a unilateral conductive hearing loss (CHL) would hear the tuning fork loudest in the affected ear. Weber test is lateralized to better ear.Masking opposite ear with Barany’s noise box to prevent transcranial transmission of sound.On application of vibrating tuning fork to deaf side the sound is transmitted to the non-test ear by bone and patient perceives this bone conduction and presumes that it is perceived by test ear, thus interpreting it as BC > AC.Īssociated conditions: Congenital causes, Skull fracture, Meningitis, Mumps, Acoustic neuroma This is seen when a patient has severe SNHL on test side and normal hearing on non-test side. Test of duration should be performed to confirm. Note: Sometimes, in testing for loudness AC = BC can be noted and this may indicate mild CHL. Ask the patient if loudness of AC or BC is greater?.Ask if he can still hear the sound or not?.After the patient signals, quickly bring the tuning fork in the position to test AC.Ask patient to signal as soon as he ceases to hear the sound. Since, the cochlear mechanism is same for both the routes, Air conduction (AC) tests the whole ear (conductive and senorineural component) while Bone conduction (BC) tests only the senosrineural component.
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