When affected left ear hears louder than the right in Weber test the patient is said to have?
Show Introduction: The Weber test is a useful, quick, and simple screening test for the evaluation of hearing loss. The test can detect unilateral conductive and sensorineural hearing loss. The External and Middle ear mediate conductive hearing. The Inner ear mediates sensorineural hearing. The Weber test is often combined with the Rinne test to detect the location and nature of hearing loss. History: The test is named after Ernst Heinrich Weber (1795–1878). Aim: The Weber test, along with its paired Rinne test, is commonly used to distinguish the site and likely cause of hearing loss. Conductive hearing loss is due to any pathology with the sound-conducting system, while sensorineural hearing loss is due to problems with the sound-transducing system, the auditory nerve or its central pathways. Occasionally, one can get a mixed hearing loss, which is a combination of the two-hearing loss. Principles of Weber test: In normal hearing, an individual will hear equally on both sides of the ear. The Weber test is a test of lateralization and is of most value useful in those with an asymmetrical hearing loss. The inner ear is more sensitive to sound via air conduction than bone conduction (in other words, air conduction is better than bone conduction). In the presence of a purely unilateral conductive hearing loss, there is a relative improvement in the ability to hear a bone-conducted sound. This can be explained by the following:
In the presence of sensorineural hearing loss, the sound will be perceived louder in the unaffected ear which has the better cochlear. Procedure of Weber test: An ideal tuning fork of choice for the Weber test would be one that has a long period of tone decay, in other words, the tone maintains and lasts long after the tuning fork has been struck and cannot be detected by sense of bone vibration. Therefore, preventing misinterpretation of the vibration as sound. In clinical practice, the 512-Hz tuning fork has traditionally been preferred. At this frequency, it provides the best balance of time of tone decay and tactile vibration. Lower-frequency tuning forks like the 256-Hz tuning fork provide greater tactile vibration. In other words, they are better felt than heard. Higher-frequency tuning forks, for example, the 1024-Hz tuning fork, have a shorter tone decay time.
Mechanism of bone conduction: Mainly there are three ways of bone conducted vibration reaching the central auditory region:
Interpretation of Weber test:
2) Unilateral Sensorineural Hearing Loss
Note: An abnormal/negative response on the affected ear (BC greater than AC) can also occur in a severe sensorineural hearing loss, also called a dead ear. This is termed a “false negative.” Rinne “true negative” only occurs if there is a conductive hearing loss element. However, when testing a dead ear, the bone conduction is perceived to be heard louder than air conduction due to cross-over of bone conduction detected by the opposite normal-functioning cochlear, resulting in a Rinne false negative. 3) Unilateral Conductive Hearing Loss
4) Symmetrical Conductive Hearing Loss
We Are Always Ready to Help You. Book An AppointmentWhat does the side heard louder indicate during Weber's test?In an affected patient, if the defective ear hears the Weber tuning fork louder, the finding indicates a conductive hearing loss in the defective ear.
Why is Weber test louder in affected ear?due to the sound localization process, in a patient with a unilateral conductive hearing loss, the sound will be louder in the affected ear (airborne sounds mask bone conduction in the normal ear; conductive loss prevents masking in affected ear è sound is perceived to be louder in affected ear)
What is lateralization of sound in Weber test?Weber test: Place the base of a struck tuning fork on the bridge of the forehead, nose, or teeth. In a normal test, there is no lateralization of sound. With unilateral conductive loss, sound lateralizes toward affected ear. With unilateral sensorineural loss, sound lateralizes to the normal or better-hearing side.
Where does Weber test localize to affected ear?Unilateral Conductive Hearing Loss
Weber test lateralizes to the affected ear. In other words, it is heard louder in the poorer ear.
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