University of Texas Dallas researchers have demonstrated that treating tinnitus or ringing in the ears, using vagus nerve stimulation (VNS)-tone therapy is safe and brought significant improvement to some of the participants in a small clinical trial.

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Sven Vanneste, PhD

Sven Vanneste, PhD, and Michael Kilgard, PhD, of the School of Behavioral and Brain Sciences used a new method pairing VNS with auditory tones to alleviate the symptoms of chronic tinnitus. Their results were published last month in the journal Neuromodulation: Technology at the Neural Interface. VNS is an FDA-approved method for treating various illnesses, including depression and epilepsy. It involves sending a mild electric pulse through the vagus nerve, which relays information about the state of the body to the brain. 

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Michael Kilgard, PhD

“The primary goal of the study was to evaluate safety of VNS-tone therapy in tinnitus patients,” Vanneste says. “VNS-tone therapy was expected to be safe because it requires less than one percent of the VNS approved by the FDA for the treatment of intractable epilepsy and depression. There were no significant adverse events in our study.”

The study, which took place in Antwerp, Belgium, involved implanting 10 tinnitus sufferers with a stimulation electrode directly on the vagus nerve. They received 2½ hours of daily treatment for 20 days. The participants had lived with tinnitus for at least a year prior to participating in the study, and showed no benefit from previous audiological, drug, or neuromodulation treatments. Electrical pulses were generated from an external device for this study, but future work could involve using internal generators, eliminating the need for clinical visits.

Half of the participants demonstrated large decreases in their tinnitus symptoms, with three of them showing a 44% reduction in the impact of tinnitus on their daily lives. Four people demonstrated clinically meaningful reductions in the perceived loudness of their tinnitus by 26 dB.

“In all, four of the 10 patients showed relevant decreases on tinnitus questionnaires and audiological measures,” Vanneste says. “The observation that these improvements were stable for more than two months after the end of the one month therapy is encouraging.”

According to Vanneste, more than 12 million Americans have tinnitus severe enough to seek medical attention, of which 2 million are so disabled that they cannot function normally. He says there has been no consistently effective treatment.

Researchers at Antwerp University Hospital and MicroTransponder Inc also contributed to the study. A larger study involving four different centers will soon begin in the United States.

Hearing Review has reported on Dr Kilgard’s work during a visit to UTD/Callier where he explained his experiments in mapping the auditory cortex and brain plasticity, as well as reporting about his 2011 paper in Nature about rebooting the brain to stop tinnitus via the vagus nerve.

Source: The University of Texas Dallas