Treatment success in relation to timing of hyperbaric oxygen therapy in idiopathic sudden sensorineural hearing loss

Idiopathic sudden sensorineural hearing loss (ISSNHL) is an otologic emergency for which hyperbaric oxygen therapy (HBOT) is a potential treatment. This study aimed to evaluate the effectiveness of HBOT in treating ISSNHL, with a focus on the timing of treatment and its impact on hearing outcomes, while also considering other factors such as demographic characteristics, clinical parameters, and treatment methods.

This retrospective cohort study analysed 70 ISSNHL patients (April 2019 to August 2024) who received steroid treatment (oral, intratympanic or both). Patients were divided into early HBOT (< 12 days), late HBOT (13-22 days), salvage HBOT (> 22 days), and no HBOT groups. Hearing improvement, measured by pure-tone audiometry (PTA), defined the treatment outcome.

Significant PTA improvements were observed in most groups (median changes: early HBOT 33.8 dB [n = 15], late HBOT 6.9 dB [n = 16], salvage HBOT 0.0 dB [n = 5], no HBOT 11.9 dB [n = 34]), with early HBOT showing greater gains than late HBOT (P < 0.001), salvage HBOT (P = 0.001), and no HBOT (P = 0.002). Receiver operating characteristic (ROC) analysis indicated that treatment within 10.5 days predicted marked improvement (AUC = 0.883, P < 0.001), and linear regression showed that each day's delay reduced PTA improvement by 0.832 dB (P < 0.001).

HBOT is effective in restoring hearing in patients suffering from ISSNHL and early treatment is associated with better outcome.