Dr Nur Ozyilmaz, NUMA Medical Director
Jonathan Joel, BSc in Cognitive and Clinical Neuroscience
Imagine a world where everyday sounds gradually fade into silence over a matter of days or abruptly vanish from one or both ears (Chandrasekhar et al., 2019). This is the reality faced by millions worldwide, as they grapple with sensorineural hearing loss (SNHL). SNHL, a condition affecting the inner ear and auditory nerve, leads to permanent hearing impairment for an estimated 5 to 20 individuals per 100,000 each year (Schreiber et al., 2010).
Sudden sensorineural hearing loss is a complex issue that can stem from multiple factors, such as natural aging, inner ear barotrauma, exposure to noisy environments, head trauma, use of ototoxic drugs, perilymphatic fistula, Meniere’s disease, vestibular schwannoma and autoimmune or genetic factors. In some cases, the cause remains unknown (idiopathic). Potential risk factors, such as cigarette smoking, hypertension, and hyperlipidemia, which can act as contributors to the development of idiopathic SNHL have been discussed in medical literature (Capaccio et al., 2007). Its varied clinical presentation and potential reversibility suggest a complex interplay of vascular, traumatic, and viral factors, with ongoing research striving to unravel the condition’s intricate mechanisms.
To this date, systemic and intratympanic steroids are currently the most commonly employed treatments for sudden sensorineural hearing loss. The challenges it poses to both patients and healthcare providers have prompted the exploration of innovative treatments for especially idiopathic SNHL, one of which is Hyperbaric Oxygen Therapy (HBOT) (Almutairi et al., 2020).
A study conducted by Rhee et al. in 2018, which assessed the effectiveness of HBOT in combination with medical therapy (MT) for SNHL, reported several key findings. In their meta-analysis involving 2401 SNHL patients, the authors found that hyperbaric oxygen therapy, when used in conjunction with systemic and/or intratympanic corticosteroids, offers a significant benefit as an adjunct treatment option. This study demonstrated that the combination of HBOT and MT leads to a significant improvement in complete hearing recovery, as well as any form of hearing improvement compared to MT alone. Notably, the benefit of HBOT was more pronounced in patients with severe to profound hearing loss at baseline, emphasizing the potential advantages for this subgroup. Additionally, the authors noted that the efficacy of HBOT was enhanced when it was used as a salvage treatment and when the total HBOT duration was at least 1200 minutes (Rhee et al., 2018). These results highlight the potential value of HBOT in the treatment of SSNHL, particularly for specific patient profiles, and underscore the need for standardized criteria for patient selection and HBOT protocols.
Recent research by Mirko Aldè et al. in 2023 highlights that HBOT is particularly effective when initiated within 72 hours after the onset of symptoms. In this study, 49 adult SNHL patients who could not receive corticosteroids due to contraindications or concerns about side effects underwent HBOT therapy. The results were remarkably encouraging: 71.4% of patients achieved complete hearing recovery after just HBOT therapy. The mean hearing threshold saw a significant improvement, decreasing from 69.8 dB to 31.4 dB. Importantly, this improvement was consistent regardless of gender, affected ear, or the initial severity of hearing loss. These findings provide hope for SNHL patients who may not opt for or tolerate corticosteroids, indicating that HBOT therapy is a valuable option for managing this time-sensitive condition.
HBOT is a medical therapy involving the inhalation of pure oxygen at elevated atmospheric pressure within a specially designed chamber. This pressurized setting enables the body to absorb oxygen at significantly higher concentrations, yielding various therapeutic benefits. First and foremost, it facilitates the delivery of oxygen to tissues and cells, even in regions with limited blood flow, critical for tissue repair and healing. Secondly, HBOT reduces inflammation and exhibits antimicrobial properties, aiding in the resolution of infections. Finally, it stimulates the release of growth factors and stem cells, further promoting tissue repair (Hajhosseini et al., 2020). The administration of HBOT for SNHL typically entails a series of sessions within a hyperbaric chamber. During each session, patients breathe in pure oxygen as the chamber’s pressure increases. The number of sessions and their duration may vary depending on the severity of SNHL and the specific treatment protocol should be recommended by a medical doctor with expertise in hyperbaric oxygen therapy individually. On average, a patient may require approximately 20 sessions. For those considering HBOT for SNHL, it is crucial to seek treatment from accredited hyperbaric facilities staffed by experienced medical professionals.
In summary, prompt and appropriate assessment and intervention could greatly enhance the quality of life for patients and decrease reliance on hearing aid devices. In the treatment of sudden sensorineural hearing loss, HBOT presents an exciting frontier. The effectiveness of HBOT is time-dependent and decreases with an increasing delay in administration. To maximize effectiveness and achieve favourable results, it is recommended to begin treatment within 72 hours of the onset of symptoms.
References
Almutairi, N., Alnofal, E., Algouhi, A., Bamajboor, A. S., & Alzaher, N. (2020). The Effectiveness of Hyperbaric Oxygen Therapy as Salvage Treatment for Sudden Sensorineural Hearing Loss: A Retrospective Study. Cureus. https://doi.org/10.7759/cureus.10819
Capaccio, P., Ottaviani, F., Cuccarini, V., Bottero, A., Schindler, A., Cesana, B. M., Censuales, S., & Pignataro, L. (2007). Genetic and Acquired Prothrombotic Risk Factors and Sudden Hearing Loss. The Laryngoscope, 117(3), 547–551. https://doi.org/10.1097/mlg.0b013e31802f3c6a
Chandrasekhar, S. S., Tsai Do, B. S., Schwartz, S. R., Bontempo, L. J., Faucett, E. A., Finestone, S. A., Hollingsworth, D. B., Kelley, D. M., Kmucha, S. T., Moonis, G., Poling, G. L., Roberts, J. K., Stachler, R. J., Zeitler, D. M., Corrigan, M. D., Nnacheta, L. C., & Satterfield, L. (2019). Clinical Practice Guideline: Sudden Hearing Loss (Update). Otolaryngology–Head and Neck Surgery, 161(1_suppl), S1–S45. https://doi.org/10.1177/0194599819859885
Eisenman, D., & Arts, H. A. (2000). Effectiveness of treatment for sudden sensorineural hearing loss. Archives of Otolaryngology–Head & Neck Surgery, 126(9), 1161–1164. https://doi.org/10.1001/archotol.126.9.1161
Hajhosseini, B., Kuehlmann, B. A., Bonham, C. A., Kamperman, K. J., & Gurtner, G. C. (2020). Hyperbaric Oxygen Therapy: Descriptive Review of the Technology and Current Application in Chronic Wounds. Plastic and Reconstructive Surgery Global Open, 8(9), e3136. https://doi.org/10.1097/GOX.0000000000003136
Mirko Aldè, Cantarella, G., Piatti, G., & Ambrosetti, U. (2013). Sudden hearing loss and early hyperbaric oxygen therapy: A preliminary study. Undersea & Hyperbaric Medicine, 50(2), 145–153. https://doi.org/10.22462/01.00.2023.18
Rhee, T.-M., Hwang, D., Lee, J.-S., Park, J., & Lee, J. M. (2018). Addition of Hyperbaric Oxygen Therapy vs Medical Therapy Alone for Idiopathic Sudden Sensorineural Hearing Loss. JAMA Otolaryngology–Head & Neck Surgery, 144(12), 1153. https://doi.org/10.1001/jamaoto.2018.2133
Schreiber, B. E., Agrup, C., Haskard, D. O., & Luxon, L. M. (2010). Sudden sensorineural hearing loss. Lancet (London, England), 375(9721), 1203–1211. https://doi.org/10.1016/S0140-6736(09)62071-7
