New Treatment Helps Alleviate Tinnitus Symptoms

A new method that pairs vagus nerve stimulation (VNS) with auditory tones can alleviate the symptoms of chronic tinnitus, according to a new study.

Researchers at University Hospital Antwerp (UZA; Belgium), the University of Texas (UT) Dallas (USA), and other institutions conducted a study involving ten patients with severe chronic tinnitus who were implanted with electrodes on their left vagus nerve. Two and a half hours each day for 20 days, the patients heard various tones, excluding the tinnitus-matched frequency, which was paired with brief electrical stimulation of the vagus nerve. The therapy was well tolerated, and no patient withdrew from the study due to complications or side effects.

The results showed that four of the ten patients exhibited clinically meaningful improvements in their tinnitus, both for the affective component (as quantified by the Tinnitus Handicap Inventory), and for the sound percept, as quantified by the minimum masking level. These improvements were stable for more than two months after the end of therapy. The researchers noted that of the ten patients, five were on medications that possibly interfered with acetylcholine and norepinephrine release induced by VNS, essential for inducing plasticity. These patients had no improvement, in contrast to medication-free patients. The study was published in the November 20, 2013, issue of the Neuromodulation.

“VNS […] involves sending a mild electric pulse through the vagus nerve, which relays information about the state of the body to the brain,” said study coauthor Sven Vanneste, MD, of the UZA Tinnitus Research Initiative Clinic. “VNS-tone therapy was expected to be safe because it requires less than 1% of the VNS approved by the FDA for the treatment of intractable epilepsy and depression. There were no significant adverse events in our study.”

Tinnitus is the perception of sound within the human ear when no actual sound is present. It is not a disease, but a condition that can result from a wide range of underlying causes, including neurological damage, ear infections, oxidative stress, foreign objects, nasal allergies, wax build-up, and exposure to loud sounds leading to noise-induced hearing loss. About 20% of people aged 55 to 65 years report symptoms on a general health questionnaire, and 11.8% on more detailed tinnitus-specific questionnaires.

Related Links:
University Hospital Antwerp
University of Texas (UT) Dallas