[Sportschosun Jang Jong-ho] Patients with sudden hearing loss were found to have a hearing recovery rate that was two to 2.5 times higher when they received hyperbaric oxygen therapy alongside standard treatment than when they received standard treatment alone. Sudden hearing loss is a condition in which sensorineural hearing loss of more than 30 dB across three consecutive frequencies appears suddenly within three days, or 72 hours, on a pure-tone audiogram. In most cases, the cause is difficult to identify. Because recovery is more likely when treatment begins early, it is treated as an emergency condition. Standard treatment includes medication such as steroids, while hyperbaric oxygen therapy is an adjunct treatment that helps damaged cochlear tissue recover by supplying high-concentration oxygen in a high-pressure environment.
Against this backdrop, the Ear Disease Center at Hana Ear, Nose and Throat Hospital, led by Director Jang Jeong-hoon and Chief Kim Jong-se, compared hearing before and after treatment in 71 patients who received hyperbaric oxygen therapy and 430 patients in a control group who received standard treatment only. The results showed that the recovery rate was consistently higher in the group that received hyperbaric oxygen therapy.
Hearing is measured in decibels, or dB, to show how faint a sound a person can hear. The World Health Organization (WHO) defines hearing below 25 dB as normal. Levels of 25 to 40 dB are considered mild hearing loss, while 41 to 55 dB is moderate hearing loss. A 10 dB difference is roughly equivalent to a twofold difference in perceived loudness. A 10 dB improvement in hearing means a person can now hear sounds that were previously inaudible at half the volume. A 20 dB improvement is perceived as about four times clearer.
In this study, the threshold for 'audible hearing' was set at within 50 dB. That level falls short of normal hearing, but it allows a person to understand everyday conversation and communicate without a hearing aid. Among patients whose hearing improved by at least 20 dB, 54.8% of those in the hyperbaric oxygen therapy group reached 'audible hearing,' compared with 42.6% in the standard treatment group, a 28.6% higher rate.
Hyperbaric oxygen therapy is a treatment method that delivers 100% oxygen to the body at more than twice normal atmospheric pressure. In the past, it was mainly used to treat carbon monoxide poisoning and decompression sickness, but it is now being applied to a wide range of conditions. In addition to sudden hearing loss, it is widely used to treat diabetic foot ulcers, complications after radiation therapy, burns and post-skin-graft complications, as well as to ease musculoskeletal injuries and help athletes recover from fatigue.
Jang Jeong-hoon, director of the Ear Disease Center at Hana Ear, Nose and Throat Hospital, said, "Because the first few days after onset determine recovery in sudden hearing loss, treatment should begin without delay if one ear suddenly feels blocked or hearing becomes difficult." He added, "In particular, combining standard treatment with intensive hyperbaric oxygen therapy has been proven effective."
Jang Jong-ho, bellho@sportschosun.com
