INTRODUCTION
Tinnitus is the most common ear disease and represents a global issue(1, 2), with a prevalence of 5.1-42.7% around the world and increases with age. (3) Guidelines of different countries stratify chronic tinnitus differently, with 3 months in Japan(4) and 6 months in China, USA and Europe(1, 5, 6). According to guidelines, acute tinnitus resolves spontaneously(1, 7), but patients with chronic tinnitus are less likely to achieve self-improvement(1); however, that may not be correct. Previous studies on chronic tinnitus have shown that 20-50% of patients may heal within 5 years(8, 9).
Tinnitus is only a clinical symptom with complex etiology. Although hearing loss is indeed an initiating factor for tinnitus, the association is not simple and direct (10). Among the various classifications and severities of hearing loss, sudden hearing loss has the most definite association with tinnitus as more than 80% of SSNHL cases have been found to be accompanied by tinnitus (11). Tinnitus in SSNHL patients often lasts for more than 6 months. Although several studies have focused on the prognosis of tinnitus accompanied by SSNHL, the follow-up times were mostly within 1 year(12-16). Therefore, we investigated the long-term outcomes of tinnitus in 161 patients with SSNHL after standard treatments. We also analyzed possible factors affecting tinnitus recovery to provide clarification and counseling for patients with residual tinnitus after SSNHL to build reasonable confidence and set appropriate expectations.