Comparison of hearing recovery criteria in sudden sensorineural hearing loss

The countless methods available to analyze hearing recovery in idiopathic sudden sensorineural hearing loss (ISSHL) cases hinder the comparison of the various treatments found in the literature. OBJECTIVE: This paper aims to compare the different criteria for hearing recovery in ISSHL found in the literature. MATERIALS AND METHODS: This is an observational clinical cohort study from a prospective protocol in patients with ISSHL, treated between 2000 and 2010. Five criteria were considered for significant hearing recovery and four for complete recovery by pure tone audiometry, using non-parametric tests and multiple comparisons at a significance level of 5%. After determining the stricter criteria for hearing recovery, vocal audiometry parameters were added. RESULTS: There was a significant difference between the criteria (p < 0.001) as they were analyzed together. Mild auditory recovery occurred in only 35 (27.6%) patients. When speech audiometry was added, only 34 patients (26.8%) showed significant improvement. CONCLUSIONS: There is a lack of consistency among the criteria used for hearing recovery. The criterion of change of functional category by one degree into at least mild hearing recovery was the stricter. Speech audiometry did not prove essential to define significant hearing recovery.