Clinical application of long-term intensity and pitch matches in fluctuating low-frequency hearing loss.

The purpose of this study was to measure changes in intensity and pitch matches to better assess disease activity in fluctuating hearing loss. Long-term suprathreshold audiometry was carried out at home on a subject with a unilateral fluctuating low-frequency hearing loss during a period when the subject demonstrated no symptoms and a period when the subject reported hearing loss, aural pressure, and tinnitus. Daily measurements of binaural intensity and pitch matches were made. Day-to-day fluctuations were clearly accentuated during the period when the subject experienced symptoms. Specifically, deviations from the reference tone were only observed for binaural pitch matches at 1 kHz during the period without symptoms; however, highly fluctuating binaural intensity and pitch matches were observed at 0.25 kHz during the period with symptoms. These fluctuations were not observed in a normal-hearing group. The results suggest that long-term measurements of binaural intensity and pitch matches can be used to monitor disease activity in fluctuating low-frequency hearing loss.