Intratympanic Versus Systemic Steroid Therapy for Idiopathic Sudden Hearing Loss: A Systematic Review and Meta-Analysis.

Idiopathic sudden sensorineural hearing loss (ISSHL) is a common condition characterized by hearing threshold reduction, most often of unknown causes. The patient experiences a sudden reduction of the hearing threshold in one or both ears. Steroids are the mainstream of the treatment. This study aims to investigate the effectiveness of intratympanic steroid administration compared with systemic administration and the combination of the two steroid treatments in the hearing recovery of patients with idiopathic sudden sensorineural hearing loss. We searched electronic databases such as PubMed, ScienceDirect, CINAHL, Cochrane (Central), Ovid, and Medline from August 31, 2021, to November 31, 2021, and from February 5 to 10, 2022. We included 12 randomized controlled trials (RCTs) and performed a meta-analysis comparing the efficiency in the hearing recovery of intratympanic versus systemic steroid treatment, systemic versus combined, and intratympanic versus combined steroid treatment. The results of the intratympanic versus systemic steroid therapy comparison showed no actual difference in efficiency and no statistical significance (odds ratio: 1.07 (Mantel-Haenszel (M-H), fixed, 95% confidence interval (CI): 0.76-1.51)). Systemic steroid treatment was inferior to combined steroid treatment and was the only outcome with statistical significance (odds ratio: 0.55 (M-H, fixed, 95% CI: 0.38-0.80)). Intratympanic steroid treatment was inferior to combined steroid treatment, although the results were not statistically significant (odds ratio: 0.65 (M-H, fixed, 95% CI: 0.37-1.16)). In conclusion, systemic steroid therapy was inferior to combined steroid therapy. The comparison of intratympanic with systemic therapy and intratympanic with combined therapy showed no statistical significance. Further research is needed with more RCTs, and side effects should be considered.