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

Diving Hyperb Med. 2026 Mar 31;56(1):41-47. doi: 10.28920/dhm56.1.41-47.

Abstract

Introduction: 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.

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.

Results: 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).

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

Keywords: Hearing loss, sudden; Hyperbaric oxygen treatment; Otologic emergency; Outcomes; Pure-tone audiometry; Treatment latency.

MeSH terms

  • Adult
  • Aged
  • Audiometry, Pure-Tone
  • Female
  • Hearing Loss, Sensorineural* / therapy
  • Hearing Loss, Sudden* / therapy
  • Humans
  • Hyperbaric Oxygenation* / methods
  • Male
  • Middle Aged
  • Retrospective Studies
  • Time Factors
  • Time-to-Treatment*
  • Treatment Outcome