Otology A4


Tuning fork tests

Weber’s test is performed with a vibrating tuning fork (usually 512 Hz) placed on the midline (typically on either the forehead or the vertex) and the patient is asked whether the sound is heard loudest on one side or equally on both sides. Lateralisation to one side is indicative of either an ipsilateral conductive hearing loss or contralateral sensorineural (or mixed) hearing loss. 

Rinne’s test is performed with a vibrating tuning fork (also 512 Hz) placed first on the mastoid process and then parallel to and ~3cm away from the external ear canal; the patient is asked which of the two positions sounds louder. A variant of this test is to let the tuning fork vibrate on the mastoid process until it can no longer be heard before moving it to the second position and asking if the sound returns. If air conduction is louder than bone conduction, this is a normal result (Rinne positive); if bone conduction is louder than air conduction then it is an abnormal result (Rinne negative). 

By using different frequencies of tuning fork (i.e. 256 Hz and 1024 Hz) along with a Barany box, one can crudely quantify the level of hearing loss (in dB). Pure tone audiometry is a much better (and routine) investigation to quantify hearing loss!

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