The results of such tests help identify the sites of lesions and and point to strategies for intervention and treatment. Patients may be screened in a relatively course way, or may be evaluated using more sophisticated testing procedures. Using a tuning fork may help evaluate the nature of a hearing loss short of an audiologic examination. Testing is typically carried out in a sound-attenuated room with the subject listening to carefully calibrated sounds. Threshold sensitivity testing using airborne pure tones.
Testing is done using earphones thereby allowing each ear to be examined independently.
Tones are reduced in intensity until they are no longer heard, at which point the examiner alternately raises and lowers the intensity of the sound until a just-detectable threshold is determined. This is repeated at several frequencies within the audible range and the results plotted as an audiogram . The shape of the curve is a measure of the frequency sensitivity of both the middle ear and the inner ear . The testing and plotting procedures are the same as with air conduction testing. In this case, however, sound is transmitted directly to the cochlea via bone conduction, thereby by-passing the transmission mechanism of the middle ear .