Pennsylvania scientists have discovered the cause of the chronic disorder known as tinnitus, and have also found a way to treat it. Their goal is a preventive strategy for individuals whose work situations could cause them to be exposed to very loud noise.
University of Pittsburgh School of Medicine researchers found that an epilepsy drug known as retigabine prevents tinnitus in animal models, according to ScienceDaily. They published their findings in the Proceedings of the National Academy of Sciences.
Strictly speaking, tinnitus isn't a condition, but a symptom of some type of disorder, like hearing loss related to age, a circulatory system ailment, or an injury to the ear, the Mayo Clinic reports. Tinnitus sufferers describe the buzzing, ringing, roaring, hissing, clicking, and other sounds it creates in their ears as annoying to varying degrees. For some, it's debilitating. Since there's no cure for tinnitus itself, doctors attempt to identify and treat the underlying cause.
According to the National Institute on Deafness and Other Communications Disorders, about 25 million Americans have suffered from tinnitus. Among those who are at least 65, the disorder affects about 14 percent of women and more than 12 percent of men.
Knowing that tinnitus is incurable and that hearing aids don't help some patients, the Pittsburgh team sought to first find the underlying cause, then a way to treat it. They knew from prior work with mice that a connection exists between tinnitus and overactive dorsal cochlear nucleus (DCN) cells in the brain through which potassium ions travel. They found that hyperactivity of DCN cells is the result of a reduced level of activity in structures known as KCNQ channels.
The researchers conducted experiments that exposed mice to regulated amounts of noise, then identified those that had developed tinnitus. They discovered that those treated with retigabine immediately after being exposed to noise didn't develop tinnitus.
The study uncovered a link between biophysical properties of potassium channels and perceiving phantom sounds. Targeting the KCNQ channels with drugs like retigabine could block the development of tinnitus in human subjects. The next goal of the Pittsburgh team is developing a drug specific to the two KCNQ channels now identified as sensitive to retigabine.
Several years ago, I suddenly noticed an odd sound in both ears. It resembled the sound that appears to come from a conch shell at the beach. Sometimes the sound was very loud. It came and went about 75 percent of the time I was awake.
After a few weeks, I saw a doctor, who gave me a diagnosis of tinnitus, but couldn't find the cause. While I've learned to cope to a degree with it as background noise, I know it's there. Now that researchers have found a tinnitus cause and a potential treatment, I have hope that at some point, the noise will finally stop.
Vonda J. Sines has published thousands of print and online health and medical articles. She specializes in diseases and other conditions that affect the quality of life.