The Analysis of Loudness Discomfort Level and Hyperacusis in Tinnitus Patients

Park, Ki Ho; Kim, Hyun Su; Kim, Young Ho; Park, Seong Won; Hong, Sun Man; Cho, Joong Hwan

Abstract

BACKGROUND AND OBJECTIVES: Hyperacusis is an abnormally strong reaction which occurs within auditory pathways resulting from exposure to moderate sound. More patients are inflicted with it than with tinnitus, accounting for a relatively high proportion of the total tinnitus patients. However, no single test could pass as an objective diagnostic test of hyperacusis. Among various psychoacoustic evaluations, loudness discomfort level (LDL) is frequently used in the evaluation of hyperacusis. Thus, this study aimed to demonstrate a proportion of hyperacusis in tinnitus patients and characterize LDL in hyperacusis and tinnitus patients as a diagnostic test. MATERIALS AND METHOD: Using 186 patients with tinnitus as experiment group and 35 acoustically normal persons as control group, pure tone audiometry (PTA), LDL, and dynamic range (DR) were checked.
RESULTS
Amongst the total number of tinnitus patients, there were 10 hyperacusis patients (5.38%). Those hyperacusis patients had much lower LDL (73.50 dB) and DR (41.50 dB) than tinnitus patients without hyperacusis (LDL: 100.90 dB, DR: 67.20 dB) as well as the control group (LDL: 104.86 dB, DR: 93.98 dB).
CONCLUSION
Hyperacusis patients consist 5.38% (10/186) and have much lower LDL than tinnitus patients without hyperacusis and the control group. There is a positive correlation between hyperacusis and LDL. Therefore, in a diagnosis of hyperacusis, it is essential to check LDL and take a careful look into the history from patients.