Stapedectomy Effects on Tinnitus: Relationship of Change in Loudness to Change in Severity.

OBJECTIVE: To relate poststapedectomy change in tinnitus loudness to change in tinnitus severity. STUDY DESIGN: Prospective, within-subjects. SETTING: A single otology and neurotology subspecialty referral practice. SUBJECTS AND METHODS: Forty-nine subjects undergoing stapedectomy completed the study between January 2012 and October 2013. Tinnitus instruments, audiometric data, and demographic information were collected prior to and 1 and 6 months after surgery. Tinnitus loudness was assessed using an 11-point (0 = none; 5 = conversation level; 10 = jet engine) visual analog scale, and severity was measured using the validated Tinnitus Functional Index. The relationship between change in tinnitus loudness and change in tinnitus severity was evaluated using linear regression and receiver operating characteristic (ROC) analyses. RESULTS: A linear regression model of change in tinnitus loudness averaged for both ears on a visual analog scale (ΔVASavg) versus change in Tinnitus Functional Index score (ΔTFI) showed a strong correlation (ΔTFI = 9.35 ×ΔVASavg; R = 0.64; P < .001). An ROC analysis identified ΔVASavg between 1.5 and 2.0 as the optimal threshold for predicting a clinically significant change in tinnitus severity (ΔTFI ≥ 13), with sensitivity and specificity of approximately 0.62 and a positive predictive value (PPV) of 0.64. CONCLUSION: For poststapedectomy patients, a VAS loudness change by 1.5 to 2.0 points averaged for both ears in bilateral tinnitus or ~3 points in unilateral tinnitus has a PPV ~0.64 for a clinically significant change in tinnitus severity.