Tuning Fork Test, Weber, Rinne and Schwabach Tests
Norm of Tuning Fork Test, Weber, Rinne and Schwabach Tests
Weber's test: The tone is heard equally well in both ears.
Rinne's test: The tone is heard twice as long by air conduction (AC) as by bone conduction (BC).
Schwabach's test: The tone is heard for the same length of time by both the client and the examiner.
Usage of Tuning Fork Test, Weber, Rinne and Schwabach Tests
Assists in the differential diagnosis of conduction and perceptive or sensorineural hearing loss, hearing disorders, and tinnitus.
Description of Tuning Fork Test, Weber, Rinne and Schwabach Tests
The Weber, Rinne, and Schwabach tests are three simple tuning-fork hearing tests.
Weber's test helps determine whether hearing loss is the result of conductive or sensorineural causes. In clients with normal hearing, a vibrating tuning fork positioned midline on the skull is heard equally well by both ears. However, in conductive hearing loss, the tone seems loudest in the affected ear; in sensorineural hearing loss, the tone seems loudest in the unaffected ear.
Rinne's test also helps differentiate conductive from sensorineural hearing loss by comparing the duration of tone perception by bone conduction to the duration of tone perception by air conduction. In a client with normal hearing, a vibrating tuning fork that can no longer be heard by bone conduction can still be heard by air conduction for twice as long. Conductive hearing loss may be secondary to blocked pathways of sound conduction in the middle or external ear; thus bone conduction will be longer than air conduction (BC > AC). Perceptive or sensorineural loss may be secondary to inner ear disease or vestibulocochlear (eighth cranial nerve) disorders; thus air conduction will be longer than bone conduction (AC > BC) but not as high as the 2:1 ratio expected in normal clients.
Schwabachs test helps evaluate bone conduction by comparing the length of time the client hears a tuning fork placed against his or her mastoid process with the length of time it is heard by a client with normal hearing.
Professional Considerations of Tuning Fork Test, Weber, Rinne and Schwabach Tests
Consent form NOT required.
Preparation
- Obtain a low-frequency tuning fork of 256–512 Hz.
- The test should take place in a quiet room, free of noise and visual distractions.
Procedure
- Weber's test:
- a. The examiner sets the tuning fork into light vibration by pinching the prongs between the thumb and index finger or by tapping it on his or her own knuckles.
- b. The tuning fork is placed on the skull at the midpoint or on the maxillary incisors.
- c. The client is asked to state whether the sound can be heard better in one ear than the other and, if so, to state which ear hears the tone more loudly.
- Rinne's test:
- a. The examiner sets the tuning fork into light vibration by pinching the prongs between the thumb and index finger or by tapping it on his or her own knuckles.
- b. The ear not being tested should be masked from detecting sound by bone conduction by providing a sound stimulus into it during step c.
- c. The vibrating fork is held by its stem on the mastoid process of the ear until vibration is no longer heard by the client.
- d. The fork is then held close to the external auditory meatus (within 2.5 cm of the pinna). If the client still hears the vibrations, this is called a positive Rinne's test. If the fork is not heard by air conduction, the test is repeated, but air conduction is first tested until the sound is no longer heard, and then the stem of the fork is placed on the mastoid process of the ear. If the sound is still heard, this is called a negative Rinne's test.
- Schwabach's test:
- a. The examiner sets the tuning fork into light vibration by pinching the prongs between the thumb and index finger or by tapping it on his or her own knuckles.
- b. The ear not being tested should be masked from detecting sound by bone conduction by providing a sound stimulus into it during step c.
- c. The vibrating fork is held by its stem on the mastoid process of the client, who is instructed to indicate whether the tone is heard. Each time he or she hears the tone, the tuning fork is quickly transferred to the mastoid process of the examiner, who listens for the tone. This process continues back and forth between the client and the examiner until the tone is no longer heard by one of them, and the results are recorded. The process is then repeated in the other ear.
Postprocedure Care
- None.
Client and Family Teaching
- Testing is noninvasive and can take up to 15 minutes.
- Thorough audiologic testing is indicated if results are abnormal.
Factors That Affect Results
- The examiner should strike the tuning fork with equal intensity for each repetition of the tests.
- For the Schwabach test, the examiner must have normal hearing for the results to be meaningful.
Other Data
- Not to be used as a general screening test.
