Verbal consent should be gained prior to performing the test.Ideally, the test should be carried out in a quiet room.Higher-frequency tuning forks, for example, the 1024-Hz tuning fork, have a shorter tone decay time. In other words, they are better felt than heard. Lower-frequency tuning forks like the 256-Hz tuning fork provide greater tactile vibration. At this frequency, it provides the best balance of time of tone decay and tactile vibration. In clinical practice, the 512-Hz tuning fork has traditionally been preferred. Therefore, preventing misinterpretation of the vibration as sound. A conductive hearing loss (in other words, when an occlusion is present) will, therefore, prevent external dissipation of these frequencies and lead to increased cochlear stimulation and increased loudness in the affected ear.Īn 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. However, some of the low-frequency sounds dissipate out of the canal. Occlusion effect: Most of the sound transmitted via bone conduction travels through to the cochlea.Therefore, the affected ear is more sensitive to bone-conducted sound. Masking effect: The sound heard via the affected ear has less environmental noise reaching the cochlea via air conduction (for example, the environmental noise is masked) as compared to the unaffected ear which receives sounds from both bone conduction and air 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. The inner ear is more sensitive to sound via air conduction than bone conduction (in other words, air conduction is better than bone conduction). The Weber test is a test of lateralization and is of most value useful in those with an asymmetrical hearing loss. In normal hearing, an individual will hear equally on both sides of the ear.
Occasionally, one can get a mixed hearing loss, which is a combination of the two-hearing loss. The Weber test, along with its paired Rinne test, is commonly used to distinguish the site and likely cause of hearing loss.Ĭonductive 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. History: The test is named after Ernst Heinrich Weber (1795–1878).
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