Comparison of Therapeutic Results with/without Additional Hyperbaric Oxygen Therapy in Idiopathic Sudden Sensorineural Hearing Loss: A Randomized Prospective Study

Clinical impact of hyperbaric oxygen therapy combined with steroid treatment for sudden sensorineural hearing loss: A case-control study

Objectives

The aim of present study was to evaluate the clinical efficacy of hyperbaric oxygen therapy (HBOT) as a primary therapy combined with standard systemic corticosteroid treatment for sudden sensorineural hearing loss (SSNHL) compared to treatment without the use of HBOT (non-HBOT) through clinical data and advanced analytical approaches.

Study Design

Case-control study.

Methods

Conducted across three Japanese medical centers involving 298 SSNHL patients diagnosed between 2020 and 2023. Inclusion criteria encompassed first onset and treatment, WHO grade 3 or 4 initial hearing impairment, receipt of systemic corticosteroid therapy within 14 days of symptom onset, and initiation of HBOT within the same timeframe for the case group. The primary outcome measure was the difference in hearing improvement (mean hearing level in decibels, dB) between the two groups, assessed by pure-tone audiometry at baseline and 3 months post-treatment, using the inverse probability of treatment weighting (IPTW) method adjusted for covariate differences.

Results

The study included 67 patients in the HBOT group and 68 in the non-HBOT group. The HBOT group exhibited significantly greater hearing improvement (IPTW-adjusted difference: 7.6 dB, 95% CI 0.4-14.7; p = 0.038). Patients without vertigo in the HBOT group demonstrated substantial hearing improvement (11.5 dB, 95% CI 2.3-20.6; p = 0.014), whereas those with vertigo showed no significant improvement (-1.8 dB, 95% CI -11.8-8.3; p = 0.729). The HBOT group also had a significantly higher association with complete recovery (IPTW-adjusted odds ratio: 2.57, 95% CI 1.13-5.85; p = 0.025).

Conclusion

In SSHNL, HBOT combination therapy yielded slightly but significantly improved hearing outcomes compared to non-HBOT treatment.

Level of Evidence

4.

The Optimized Protocol of Hyperbaric Oxygen Therapy For Sudden Sensorineural Hearing Loss

OBJECTIVE

This study aimed to determine the optimal protocol of hyperbaric oxygen therapy (HBOT) according to various treatment settings for sudden sensorineural hearing loss (SSNHL).

METHODS

A 112 patients with SSNHL were enrolled in this prospective study. All patients were treated with systemic steroid therapy, intratympanic steroid therapy, and HBOT. According to the pressure and duration of HBOT (10 sessions in total), the patients were divided into three groups: group 1, 2.5 atmospheres absolute (ATA) for 1 h; group 2, 2.5 ATA for 2 h; and group 3, 1.5 ATA for 1 h. The pure-tone average (PTA), word discrimination score (WDS), and mean gain were compared.

RESULTS

A total of 105 patients completed the 3-month follow-up, and 6 patients were excluded. Differences among groups were found in PTA, WDS, and mean gain. In the post-hoc analysis, group 3 had significantly lower WDS and mean gain than groups 1 and 2; however, group 2 showed no significant differences from group 1. The proportion of patients with hearing recovery after treatment was significantly higher in group 1 (57.6%) and group 2 (58.8%) than in group 3 (31.3%).

CONCLUSIONS

When HBOT (10 sessions) was combined with corticosteroids as the initial therapy for SSNHL, a higher pressure (1.5 ATA vs. 2.5 ATA) provided better treatment results; however, increasing the duration (1 h vs. 2 h) under 2.5 ATA did not result in a significant difference. Therefore, HBOT for SSNHL may be performed at 2.5 ATA for 1 h in 10 sessions. Laryngoscope, 133:383-388, 2023.

Comorbidities and laboratory changes of sudden sensorineural hearing loss: a review

Sudden sensorineural hearing loss (SSNHL) is defined as an abrupt hearing loss of more than 30 dB in three contiguous frequencies within 72 h. It is an emergency disease requiring immediate diagnosis and treatment. The incidence of SSNHL in Western countries' population is estimated between 5 and 20 per 1,00,000 inhabitants. The etiology of SSNHL remains unknown. Due to the uncertainty of the cause of SSNHL, at present, no specific treatment targets the cause of SSNHL, resulting in poor efficacy. Previous studies have reported that some comorbidities are risk factors for SSNHL, and some laboratory results may provide some clues for the etiology of SSNHL. Atherosclerosis, microthrombosis, inflammation, and the immune system may be the main etiological factors for SSNHL. This study confirms that SSNHL is a multifactorial disease. Some comorbidities, such as virus infections, are suggested to be the causes of SSNHL. In summary, by analyzing the etiology of SSNHL, more targeting treatments should be used to achieve a better effect.

The value of having an initial word recognition score for a precise prognosis of idiopathic sudden sensorineural hearing loss

OBJECTIVE

Although the hearing thresholds of patients with idiopathic sudden sensorineural hearing loss (ISSNHL) closely relate to the prognosis that results in progressive floor effects, many studies have usually used hearing thresholds as the main outcome of the measurement of prognostic factors. The present study aimed to identify the prognostic factors related to initial hearing tests and speculates the effects of word recognition score (WRS) on the prognoses for patients with ISSNHL.

METHODS

Between March 2011 and November 2020, we retrospectively reviewed chart profiles of 2,636 ISSNHL patients. The 180 patients who met the inclusion criteria were asked to participate in the present study. Based on their initial WRS, all these patients were divided into good WRS (GW) and poor WRS (PW) groups with 52% as the cut-off points. Demographic, clinical, and audiological variables, such as age, onset time, duration of treatment, gender, ear side, comorbidities (i.e., hypertension, diabetes mellitus, tinnitus, dizziness), hearing configuration (i.e., ascending, descending, flat, irregular, and profound), treatment options (i.e., systemic corticosteroid therapy per oral, intratympanic steroid injection, and hyperbaric oxygen therapy), and WRS were analyzed as being underlying prognostic factors.

RESULTS

Both groups showed significantly different distributions for hearing thresholds and hyperbaric oxygen therapy (HBOT) as general characteristics. The results of a multivariate logistic regression analysis showed that the odds ratio (OR) of age (OR: 0.96, 95% CI: 0.59 - 24.25), duration of treatment (OR: 0.98, 95% CI: 0.96 - 1.00), ascending configuration (OR: 4.97, 95% CI: 1.64 - 16.62), irregular configuration (OR: 4.58, 95% CI: 1.62 - 13.79), and WRS (OR: 1.01, 95% CI: 1.00 - 1.02) were the significant prognostic factors for all the patients. Further analysis of those patients with WRS under 52% cut-off points showed that an ascending configuration (OR: 5.87, 95% CI: 1.18 - 35.99), irregular configuration (OR: 8.03, 95% CI: 1.69 - 46.30), and WRS (OR: 1.05, 95% CI: 1.01 - 1.10) significantly affected the prognosis. As the initial WRS of ISSNHL patients decreased, the OR of the WRS itself increased. These results suggested that the importance of WRS as the prognostic factor was stressed for PW patients.

CONCLUSION

The age, duration of treatment, initial hearing configuration (ascending and irregular types), and WRS were the significant prognostic factors for patients with ISSNHL. It was learned that WRS could be a remarkable prognostic factor to consider, especially for ISSNHL patients with poor WRS.