Intratympanic Dexamethasone in Sudden Sensorineural Hearing Loss: A Systematic Review and Meta-Analysis

Objective: Systemic dexamethasone has demonstrated conclusive benefits in reversing sudden sensorineural hearing loss (SSNHL) despite considerable number of potential side effects. In contrast, the intratympanic route of steroid administration averts several possible complications. This study aims to examine the literature to delineate the efficacy and side effect of intratympanic dexamethasone (ITD) injection for the treatment of SSNHL. Data Source: Cochrane, Embase, and MEDLINE electronic databases from January 1950 to August 2014, with an update performed on November 10, 2014. Review Methods: Systematic review and meta-analysis of randomized controlled clinical trials (RCCTs), using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagram and guidelines. Quality assessment was performed using The Cochrane Collaboration Tool for Assessing Risk of Bias. Results: Eight RCCTs on SSNHL were included Three of the eight studies had high risk of bias. Substantial heterogeneity was found. The meta-analysis failed to detect statistically significant difference between ITD and alternative treatment ( odds ratio = 0.39, 95% credible intervals = 0.11-1.27). The side-effects profile was favorable for ITD. No serious adverse events were recorded. Conclusion: There is no sufficient scientific evidence to support a difference between ITD and alternative therapy for SSNHL. We recommend larger RCCTs to determine the effectiveness of ITD compared to oral steroid therapy. We encourage a shift in study design selection toward noninferiority or superiority studies. Avoiding systemic corticotherapy, especially in vulnerable populations, should be the rationale for future research in the field.