The effectiveness of hyperbaric oxygen therapy on the final outcome of patients with sudden sensorineural hearing loss

To evaluate the therapeutic effect of the combination of systemic steroids (SS) and hyperbaric oxygen therapy (HBOT) in patients with idiopathic sudden sensorineural hearing loss (SSNHL).Fifty patients with idiopathic sudden sensorineural hearing loss were allocated into 2 groups: the control group received Dexamethasone IV (SS) and the therapy group received Dexamethasone IV combined with 15 sessions of hyperbaric oxygen therapy (SS + HBOT) as initial treatment. Hearing assessment was performed at the admission to hospital and 3 months after the onset of treatment. Siegel's criteria were used to evaluate the hearing outcomes. Prognostic factors were identified by linear regression analyses.Hearing improvement rate was 64 % in the therapy group and 56 % in the control group, difference which was not statistically significant (p = 0.369). Furthermore, when patients of each group were categorized into 5 subgroups by disease severity (mild, moderate, moderate to severe, severe, profound), differences in treatment outcome between the subgroups of the same severity were not significant. A descending type audiogram curve was proven an unfavorable prognostic factor in both groups, as it led to a significantly lower hearing gain (30 dB) compared to other curve shapes (b = -29.10, 95 % CI = -56.39, -1.82).The addition of hyperbaric oxygen therapy to systemic steroids caused no significant hearing improvement, despite a mild tendency toward a greater improvement rate within the combination group. More prospective randomized trials with larger series of patients could shed even more light on the effectiveness of combination therapy (SS + HBOT) in patients affected by SSNHL.