Negative Rinne's test for 256 Hz tuning fork indicates a minimum air-bone gap of
Rinne's test: Is named after Adolf Rinne of Gottingen, who described this test in 1855 It compares the patient ability to hear a tone conducted air and bone - the mastoid process. The base of a vibrating tuning fork is first placed on the mastoid process and then after the sound is no longer appreciated the vibrating top is held one inch from the external auditory meatus The patient is asked whether the sound is louder behind or in front - referring to bone and air conduction respectively Normally the note is audible at the external meatus When nerve deafness is present then the note is audible at the external meatus, as air and bone conduction are reduced equally, so that the air conduction is better (as is normal) than bone conduction - this is termed Rinne-positive (AC is longer/louder than BC). It is seen in normal person or those having sensorineural deafness. Rinne-negative occurs with a conductive hearing loss - no note is audible at the external meatus (i.e. bone conduction is better than air conduction). A prediction of the air-bone gap can be made if tuning forks of 256, 512 and 1024 are used. A negative Rinne test for 256, 512 and 1024 Hz indicates a minimum air-bone gap of 15, 30 and 45 dB respectively.
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