Electrocochleography in Chronic Tinnitus: Correlations with Audiological Profiles and Psychological Distress

This study aimed to explore the electrophysiological characteristics of patients with chronic tinnitus through electrocochleography (ECochG) findings and determine if these findings correlate with specific audiological patterns that could differentiate tinnitus patients from those without this condition.

A retrospective analysis of medical records from patients who visited a tinnitus clinic at a tertiary university hospital between March 2020 and December 2023 was conducted. Inclusion criteria were non-pulsatile subjective tinnitus lasting over three months, and ECochG performed at initial evaluation. Audiological assessments and ECochG results were analyzed, with the SP/AP ratio being a focal point.

Among 256 patients, an elevated SP/AP ratio was observed in 37.5 % of patients. No significant difference in ECochG outcomes was noted based on tinnitus laterality. Patients with an elevated SP/AP ratio reported more sleep disturbances, higher depression scores, attention problems, and aural fullness. These patients also exhibited lower loudness discomfort levels and low-frequency hearing losses. Significant correlations were found between elevated SP/AP ratios and DPOAE responses.

The findings highlight the SP/AP ratio in ECochG as a valuable biomarker for assessing clinical and psychological aspects of tinnitus, indicating its potential utility in tailoring treatment strategies. Elevated SP/AP ratios were associated with sleep disturbances, depression, attention problems, aural fullness, hyperacusis, and low-frequency hearing loss, suggesting a complex interplay between cochlear pathology and tinnitus perception. This study underscores the need for a nuanced understanding of ECochG results in the clinical evaluation of tinnitus, potentially guiding more personalized management approaches.