Hearing Outcomes After Intratympanic Dexamethasone for Sudden Sensorineural Hearing Loss

Introduction: Intratympanic dexamethasone injections are commonly used to treat sudden sensorineural hearing loss (SSNHL), yet optimal dosing remains unclear. This study evaluated whether dexamethasone concentration and injection frequency are associated with audiologic outcomes.

Methods: We conducted a retrospective chart review of 350 patients treated for SSNHL with intratympanic dexamethasone injections at a single academic center. Inclusion required four-frequency pure-tone average (PTA) audiograms pre- and post- treatment; complete data were available for 296 patients. Extracted data included dexamethasone concentration and number of injections. The primary outcome was change in PTA. The secondary outcome was clinically meaningful hearing recovery defined as ≥10 dB PTA improvement. Dexamethasone concentration was analyzed as 10 mg/mL versus 24 mg/mL. Injection frequency was evaluated both as grouped categories (1, 2, and ≥3 injections) and as a continuous variable. Between-group comparisons used Welch two-sample t-tests and Wilcoxon rank-sum tests. Multivariable linear regression assessed associations between PTA change, concentration, injection frequency, and their interaction. Logistic regression evaluated odds of ≥10 dB improvement.

Results: Rates of ≥10 dB improvement were similar between concentration groups (41.8% for 10 mg/mL vs 40.5% for 24 mg/mL). Mean PTA improvement did not differ (11.1 vs 7.9 dB; p = 0.15). Injection frequency was not associated with PTA change when analyzed categorically (p = 0.43) or continuously (slope −0.004 dB per injection; p = 0.995). Multivariable regression showed no association between concentration and PTA change (p = 0.10) or concentration–injection interaction (p = 0.80). Logistic regression showed no difference in odds of ≥10 dB improvement by concentration (OR 0.95; p = 0.84).

Conclusions: In this retrospective cohort, higher dexamethasone concentration and greater injection frequency were not associated with improved audiologic outcomes, suggesting escalation within commonly used dosing ranges may not confer additional benefit.