Dear Doctors: I've been diagnosed with sudden sensorineural hearing loss. None of the doctors I've seen can tell me why it happened. My understanding is that hyperbaric therapy is a possible treatment. What does that entail, and who would I approach for that kind of treatment?
Dear Reader: Sudden sensorineural hearing loss, or SSHL, is sometimes called “sudden deafness.” The definition is contained in the name, so let's break that down. The word “sudden” refers to hearing loss that goes from normal to greatly diminished in 72 hours or less. The word “sensorineural” indicates that the structures of the inner ear and the nerve pathways that connect to the brain have somehow become damaged.
Sound is measured in decibels, and in SSHL, the degree of hearing loss is at least 30 decibels. That's roughly one-fourth of the range of volume of human hearing. This type of hearing loss affects sounds in the high, low and middle registers. For someone with SSHL, conversation at a normal volume might sound like the participants are barely whispering.
It is estimated that at least 5,000 new cases of SSHL occur every year. However, the condition often goes undiagnosed, so the numbers are likely higher. It can happen at any age, but it is most common in adults in their late 40s and early 50s. In addition to sudden deafness, the condition may be accompanied by ringing in one or both ears and dizziness. Contributing factors can include head trauma, infection, autoimmune or vascular diseases, certain medications, neurological disorders and disorders of the inner ear. In the majority of cases, though, an exact cause cannot be identified.
The most common treatment for SSHL is the use of corticosteroids to ease inflammation. When infection is suspected, antibiotics or antivirals may be prescribed. And yes, the FDA has approved the use of hyperbaric oxygen therapy, or HBOT, for this condition.
HBOT is a treatment in which someone breathes pure oxygen while in a pressurized chamber or room. Some cases of SSHL arise due to impaired blood flow to the inner ear. With HBOT, additional oxygen is delivered to those tissues.
Several small studies over the years have found that this therapy can lead to improved hearing in some individuals. The treatment consists of 10 to 20 90-minute sessions in a hyperbaric chamber. HBOT has proven most successful when initiated soon after the onset of hearing loss.
Begin by discussing your interest in HBOT with your health care provider. Medical history and general health each play a role in whether someone is a candidate. If a decision is made to move forward, your doctor will prescribe the treatment. The therapy is available at many medical centers.
When HBOT is not available in a medical setting, patients can seek outside providers. It's important to choose a center with a medical-grade chamber that is regularly maintained by certified specialists. The medical director of the clinic should be board-certified in hyperbaric medicine, and the clinic should be staffed by certified specialists. You will also want to check with your insurer, as not all plans cover the treatment.
(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)
