Audiology
Alternative names:
audiogram; audiography; audiometry; hearing test
Normal values:
The unimpaired ability to hear a whisper, normal speech, and a ticking watch is normal. The unimpaired ability to hear a tuning fork through air and bone is normal.
Audiography screening usually includes 2 tones of 256 cps and 4,096 cps delivered at 5 and 10 dB (the normal speech range). Detailed audiography shows normal hearing, with low tones (around 64 cps) heard at 1 or 2 dB and high tones (11,584 cps) heard at around 10 dB, and tones in between this range all heard at less than 10 dB.
What abnormal results mean:
There are many different kinds and extents of hearing loss. Some include only the loss of the ability to hear high or low tones, or the loss of only air or bone conduction. The inability to hear pure tones below 10 dB indicates some extent of hearing loss. The extent and kind of hearing loss may give clues to the cause and the prognosis (probable outcome).
Conditions that may affect test results:
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