What is the Weber tuning fork test?
IntroductionRinne’s and Weber’s tests are simple tuning fork tests used to screen for the presence of conductive and sensorineural hearing loss. They are usually performed as part of a comprehensive ear examination. Show
It is important to be able to interpret the results of Rinne’s and Weber’s, as these tests frequently appear in OSCEs and written examinations. How to perform Rinne’s test1. Place a vibrating 512 Hz tuning fork firmly on the mastoid process (apply pressure to the opposite side of the head to make sure the contact is firm). This tests bone conduction. 2. Confirm the patient can hear the sound of the tuning fork and then ask them to tell you when they can no longer hear it. 3. When the patient can no longer hear the sound, move the tuning fork in front of the external auditory meatus to test air conduction. 4. Ask the patient if they can now hear the sound again. If they can hear the sound, it suggests air conduction is better than bone conduction, which is what would be expected in a healthy individual (this is often confusingly referred to as a “Rinne’s positive” result). Interpretation of Rinne’s testIn healthy patients, air conduction (using the structures in the ear) should be better than bone conduction (conduction of vibrations via bone). Therefore, the patient should be able to hear the tuning fork held over the external auditory meatus (which is testing air conduction) for longer than the tuning fork held on the mastoid (testing bone conduction). If there is a problem with air conduction (i.e. conductive hearing loss), then bone conduction may be better than air conduction. In this situation, the patient will be able to hear the tuning fork for longer when held on the mastoid (testing bone conduction) than when held over the external auditory meatus (testing air conduction). However, a patient with significant sensorineural hearing loss may have a ‘false negative’ Rinne’s test, as they are unable to hear anything in the affected ear but bone vibrations may be transmitted to the unaffected ear. How to perform Weber’s testExplain to the patient that you are going to test their hearing using a tuning fork. 1. Tap a 512Hz tuning fork and place in the midline of the forehead. The tuning fork should be set in motion by striking it on your knee (not the patient’s knee or a table). 2. Ask the patient “Where do you hear the sound?” A 512Hz tuning fork is used as it gives the best balance between time of decay and tactile vibration. Ideally, you want a tuning fork that has a long period of decay and cannot be detected by vibration sensation. Interpretation of Weber’s testWeber’s test should be assessed in context with the results of Rinne’s test before any diagnostic assumptions are made:
*In conductive hearing loss, there is a relative improvement in bone conduction on the affected side. The affected ear has less environmental noise (due to the problem with air conduction). In addition, low-frequency sounds are ‘trapped’ within the inner ear by the obstruction leading to increased loudness in the affected ear. You can demonstrate this by speaking/humming, and then occluding an external auditory meatus. You will notice your voice is louder in the occluded ear. Interpretation of Rinne’s and Weber’s tests
Conductive vs sensorineural hearing loss
Key points
 What does the Weber test test for?The Weber test has been mainly used to establish a diagnosis in patients with unilateral hearing loss to distinguish between conductive and sensorineural hearing loss. It is a useful, quick, and simple screening test for evaluating hearing loss. The test can detect unilateral conductive and sensorineural hearing loss.
What is the purpose of a tuning fork test?Key points
General practitioners can use otoscopy and the tuning fork tests to differentiate between conductive and sensorineural hearing loss. Tuning fork tests remain useful and are used in daily ENT practice.
What is Weber and Rinne test?What are Rinne and Weber tests? Rinne and Weber tests are exams that test for hearing loss. They help determine whether you may have conductive or sensorineural hearing loss. This determination allows a doctor to come up with a treatment plan for your hearing changes.
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