Nerve deafness can occur as partial or total hearing loss as a result of damage to the inner ear. Idiopathic sudden sensorineural hearing loss, ISSNHL, is a sudden loss of hearing greater than 30dB. It occurs in 3 frequencies over a period of less than 72 hours. This type of hearing loss can range from very mild to severe and usually occurs in one ear. Sudden deafness can be combined with noise in the ear, also known as tinnitus, and constant feeling of pressure. Vertigo and frequency range problems have also been reported as accompanying side effects of nerve deafness. The onset of this condition is usually very abrupt and the number of incidences increases with age.
For many patients, spontaneous recovery of nerve deafness occurs within the first 2 weeks of the condition. However, this is not always the case and permanent hearing loss can occur. Someone experiencing idiopathic sudden sensorineural hearing loss must act quickly in order to prevent permanent damage. The most effective treatment of nerve deafness occurs within the first few months of sudden hearing loss.
Hyperbaric oxygen therapy has been used on its own, as well as with other treatment options in order to help reduce the effects of hearing loss. The use of a hyperbaric chamber allows a patient to experience 100 percent oxygen at greater atmospheric pressure. This safe, non-invasive treatment greatly increases the amount of oxygen that flows through the blood. HBOT has been proven to help patients with nerve deafness. It has been reported to improve hearing loss associated with ISSNHL since the late 1960’s. Extensive research and studies have been conducted with regard to hyperbaric treatments for general hearing loss as well.
Hyperbaric oxygen treatment of idiopathic sudden sensorineural hearing loss has the highest success rate when begun within a few months of the onset of nerve deafness. HBOT offers a much greater flow of oxygen to the inner ear, promoting blood circulation and regeneration. It has been shown to reduce the severity of nerve deafness and lessen the impacts of sudden hearing loss. By increasing the amount of oxygen in the inner ear fluids, HBOT is able to provide a reversal of hearing loss symptoms and in many cases, eliminate them completely.
Bennett MH, Kertesz T, Yeung P. Hyperbaric oxygen for idiopathic sudden sensorineural hearing loss and tinnitus (Cochrane Review). In: The Cochrane Library, Issue 1, 2006. Oxford: Update Software.
Five trials contributed to this review (254 subjects, 133 receiving HBOT and 120 control). Pooled data from two trials involving 114 patients (45% of the total) suggested there was a trend towards, but no significant increase in, the chance of a 50% increase in hearing threshold on Pure Tone Average (PTA) over four frequencies when HBOT was used (relative risk (RR) for good outcome with HBOT 1.53, 95% confidence interval (CI) 0.85 to 2.78, P = 0.16). The chance of achieving a 25% increase with HBOT was, however, statistically significant (RR 1.39, 95% CI 1.05 to 1.84, P = 0.02). Fifty-six per cent of the control subjects achieved this outcome versus 78% of the HBOT subjects, with the number-needed-to-treat (NNT) to achieve one extra good outcome being 5 (95% CI 3 to 20). A single trial involving 50 subjects (20% of the total) also suggested a significant improvement in the mean PTA threshold expressed as a percentage of baseline (61% improvement with HBOT, 24% with control, WMD 37%, 95% CI 22% to 53%).
Idiopathic sudden sensorineural hearing loss (ISSHL) is an acute hearing impairment, with an incidence of about 8 to 15 per 100,000 of the population per year (Stokroos 1996). Although, the aetiology and pathophysiology remain unclear (Haberkamp 1999), ISSHL is most commonly defined as a greater than 30 dB sensorineural hearing loss occurring in at least three contiguous audiometric frequencies over 72 hours or less (Hughes 1996). Tinnitus can be described as the perception of sound in the absence of external acoustic stimulation, and in many cases it is associated with some degree of hearing loss, particularly in those individuals who have been exposed to excessive noise. The incidence is probably around 10% to 20% of adults in the developed countries (ATA 2001; Coles 1990). For the patient it may be trivial or it may become a debilitating illness (Luxon 1993). Sufferers from tinnitus hear a noise that apparently arises from the ears or within the head and may be continuous or intermittent. Brief episodes of tinnitus are probably normal, and clinically significant tinnitus is usually defined by applying one of several classification systems proposed (Dauman 1992; Stephens 1991).
Hyperbaric oxygen therapy in idiopathic sudden sensorineural hearing loss (ISSNHL) in association with combined treatment. Holy R, Navara M, Dosel P, Fundova P, Prazenica P, Hahn A. ENT Clinic, 3rd Faculty of Medicine, Charles University, Prague, Czech Republic. firstname.lastname@example.org
The main basic effect of hyperbaric oxygenation (HBO2) on the human body, in our study, was an increased partial pressure of oxygen resulting from an increased amount of oxygen dissolved in plasma. Thus the plasma can become capable of carrying enough oxygen to meet the needs of the body's tissues. From 1 January 2004 to 31 December 2007, a total of 61 patients (62 ears) received medical treatment at the ENT clinic of the 3rd Faculty of Medicine, Charles University, and at the Central Military Hospital in Prague. Treatment consisted of a combination of vasodilatation infusion treatment and HBO2 therapy. The results were evaluated in a retrospective study. The overall percentage of patients showing improvement was 59.7%. However, for those patients who started HBO2 treatment within 10 days of onset, complete recovery, or significant improvement was noted in 65.9%. In contrast, patients who started treatment after 10 days of onset, improvement was noted in only 38.9%. NMR examination revealed that two patients had vestibular schwannoma (also known as acoustic neuroma).