Effect of Hyperbaric Oxygen Therapy in Comparison to Conventional or Placebo Therapy or No Treatment in Idiopathic Sudden Hearing Loss, Acoustic Trauma, Noise-Induced Hearing Loss and Tinnitus. A Literature Survey

Abstract

With the published clinical data to hand on the therapeutic results of patients with idiopathic sudden hearing loss, acoustic trauma or noise-induced hearing loss, it may be confirmed that 65% of those polypragmatically treated patients demonstrated a hearing improvement of 19 +/- 4 dB. In 35% of the cases, no hearing improvement was detected independent of the drugs administered. This corresponds to the results obtained from placebo-treated patients who demonstrated a hearing improvement of 20 +/- 2 dB in 61% of cases and no hearing gain in 39% of cases (fig. 1). A different set of results was obtained from patients with a hearing loss who were treated either with prednisolone or placebo. The percentage of patients who achieved normal hearing again in the placebo-treated group amounted to 31% and 38% and in the verum-treated group 50% and 78%. It may be concluded that a placebo therapy is equally effective to that of all nonsteroidal drugs. Problems arise when comparing non-treated patients since information on spontaneous remission rates differs greatly in the references, i.e. between 25-68% for spontaneous full remissions and 47-89% for spontaneous partial remissions. From a statistical view, 35% and 39% of patients experienced no success with nonsteroidal drugs or placebo, respectively. These patients can still be helped with HBO therapy. 18 patients only underwent primary HBO therapy. In all other 50 studies evaluated here with a total of 4, 109 patients suffering from idiopathic sudden hearing loss, acoustic trauma or noise-induced hearing loss and/or tinnitus, HBO therapy was administered as a secondary therapy, i.e. following unsuccessful conventional therapy. If the onset of affliction was more than 2 weeks but no longer than 6 weeks, one half of the cases showed a marked hearing gain (in at least 3 frequencies of more than 20 dB), one-third showed a moderate improvement (10-20 dB) and 13% showed no hearing improvement at all (fig. 2). 4% no longer experienced tinnitus, 81.3% observed an intensity decrease and 1.2% an intensity increase of their tinnitus condition. 13.5% remained unchanged (fig. 2). If HBO therapy was administered at a later stage, but still within 3 months following onset of affliction, 13% showed a definite improvement in hearing, 25% a moderate improvement and 62% no improvement at all. 7% no longer suffered from tinnitus, 44% reported an intensity decrease, a similar percentage noticed no change and 5% a temporary deterioration of their tinnitus condition. If the onset of affliction was longer than 3 months up to several years, no hearing improvement can be expected in the majority of patients (fig. 3); however, one third of the cases reported an intensity decrease of tinnitus, 60-62% reported no change and 4-7% noticed a temporary intensity increase (fig. 4). In conclusion, it may be deduced that HBO therapy is recommended and warranted in those patients with idiopathic sudden deafness, acoustic trauma or noise-induced hearing loss within 3 months after onset of disorder.

Hyperbaric Oxygen Therapy as Salvage Therapy for Sudden Sensorineural Hearing Loss

“…[11] It was found that perilymphatic oxygen tension decreased in patients with SSNHL, while under hyperbaric conditions, oxygen tension in the perilymphatic fluid increased by 450% [12,13] . These days, HBO therapy is used as primary or as salvage therapy for sudden haring loss [14][15][16] .…”

The Effects of Nonylphenol on Hearing in Rats

“…DPOAEs were measured with a microphone in the external ear canal at 2f1-f2 frequency and the signal-to-noise ratio (SNR) at 1001, 1501, 2002, 3003, 4004, 6006, and 7996 Hz frequency bands of the geometric mean of f1 and f2 was based on. To assess the DPOAE responses, SNR is more reliable when compared to DPOAE amplitudes [6] . We carried out the evaluation process, based on SNR at 1000-8000 Hz frequencies.…”

Hyperbaric Oxygen Therapy: Focus

“…For doctors who advocate the interest of HBOT, the indication is based on the fact that HBOT increases the oxygen partial pressure in the inner ear [17], improves blood viscosity and elasticity globular [18]. A review of the literature suggests a potential benefit of HBOT in cases of sudden refractory deafness after two weeks of vasodilator therapy and/or corticosteroids, provided that treatment is given within three months of onset [19]. However, this review of the literature does not differen- …”