Systematic review and meta-analysis of intratympanic steroid injection in sudden sensory neural hearing loss as initial, combined, or salvage treatment compared to systemic steroids alone

<sec><strong>Background</strong> Sudden sensorineural hearing loss (SSNHL) is a rapid condition of hearing impairment, typically occurring over 72 hours and affecting the inner ear or auditory nerve pathways. The etiology of SSNHL remains largely idiopathic, with potential causes including viral infections, vascular occlusions, and autoimmune disorders. Traditional treatment primarily involves systemic corticosteroids, but their efficacy is inconsistent, leading to exploring alternative and adjunctive therapies such as intratympanic steroid (ITS) injections. </sec> <sec><strong>Objective</strong> This Systematic Review and Meta-Analysis intends to determine the effectiveness of ITS injections as an initial treatment, combined therapy, or salvage treatment for SSNHL compared to systemic steroids alone. </sec> <sec><strong>Methods</strong> An inclusive study was performed through the PubMed, Scopus, Web of Science, and Cochrane Library databases, encompassing publications published from 2015 to 2024. Case-control studies, cohort studies, randomized controlled trials (RCTs), and systematic reviews were included. Two separate reviewers read the studies and extracted data on steroid administration methods, study outcomes, and risk of bias (ROB) using the Cochrane Collaboration Tool and RevMan 5.4. </sec> <sec><strong>Results</strong> The review included 12 studies with varied designs, including prospective RCTs, systematic reviews, and retrospective analyses. Combined ITS and systemic steroid therapy showed superior hearing recovery compared to systemic steroids alone in several studies. ITS alone demonstrated variable efficacy, with some studies indicating benefits, particularly as a salvage therapy. ROB assessment revealed variability in methodological rigor, with studies like those of Li &amp; Ding et al. (2020) and Devantier et al. (<xref ref-type="bibr" onclick="findReferencesById(event)" class="bDevantier2022" rid="bDevantier2022">2022</xref>) showing low risk, while others exhibited higher risks, particularly in random sequence generation and allocation concealment. </sec> <sec><strong>Conclusion</strong> The findings suggest that ITS injections, particularly when combined with systemic steroids, can enhance hearing recovery in SSNHL patients. However, variability in study outcomes and methodological quality underscores the need for standardized protocols and further high-quality RCTs. This analysis underscores the prospective advantages of ITS therapy while stressing the need for stringent study designs to enhance SSNHL treatment methodologies. </sec>