A Tinnitus Evaluation may consist of:
- Pitch matching
- Loudness matching
- Measure of residual inhibition
Each test is also described below.
Pitch matching attempts to quantify tinnitus in terms of its possible frequency. It is used as a reference point for discussion for the clinician and patient. It is also used for the fitting of tinnitus maskers.
Tones are presented to the patient and the patient is asked to choose which one most closely matches the tinnitus that they hear. This is continued until the match is made.
The results of the pitch match are very useful in the counseling of a tinnitus sufferer. First of all, it helps to validate the presence of tinnitus, which can be very comforting to the patient. The patient now knows that the tinnitus is real and that he/she is not just imagining it. Secondly, the pitch match is used for the selection and fitting of tinnitus maskers.
Loudness matching attempts to quantify the tinnitus in decibels. Similar to pitch matching, this test is also used in the counseling of the tinnitus patient. Tinnitus is usually found to be only a few decibels above a person’s threshold for the frequency being tested (Henry & Meikle, 2000; Goldstein & Shulman, 1997). One procedure for loudness matching suggested by Goldstein and Shulman, (1997) is to start at a level just below threshold and increase intensity until the patient signals a match. They use a frequency that is at or near the frequency that was matched to the patient’s tinnitus.
Residual Inhibition Test
The purpose of testing for residual inhibition is to determine whether the use of tinnitus maskers would be a viable treatment course (Shulman & Goldstein, 1997).
Residual inhibition is defined as the temporary suppression and/or disappearance of tinnitus following a period of masking (Goldstein & Shulman, 1997). To test for residual inhibition the clinician should use the tinnitus frequency at 10dB above the loudness match for one minute. Then the post-masking effects are classified into four categories. These categories are:
- 1) positive-complete, where the tinnitus is completely absent for more than one minute
- 2) positive-partial, where the tinnitus is still present but softer at a lower perceived level than before for more than one minute
- 3) negative, where there is no reported change in the tinnitus; and finally
- 4) rebound, where the tinnitus is actually louder after the masking stimulus is presented.