Vagus nerve stimulation via implant improves tinnitus
21 November 2013
A small clinical trial has found that treating tinnitus using vagus
nerve stimulation-tone therapy is safe and brought significant
improvement to some of the participants.
Researchers at the School of Behavioral and Brain Sciences at the
University of Texas, Dallas, used a new method pairing vagus nerve
stimulation (VNS) with auditory tones to alleviate the symptoms of
chronic tinnitus. Their results were published on Nov. 20 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.
The study, which took place in Antwerp, Belgium, involved
implanting 10 tinnitus sufferers with a stimulation electrode
directly on the vagus nerve. They received two and a half 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
implanted 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 decibels.
Five participants, all of whom were on medications for other
problems, did not show significant changes. However, the four
participants who benefited from the therapy were not using any
medications. The report attributes drug interactions as blocking the
effects of the VNS-tone therapy.
“The primary goal of the study was to evaluate safety of VNS-tone
therapy in tinnitus patients,” said Dr Sven Vanneste. “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
“In all, four of the ten patients showed relevant decreases on
tinnitus questionaires and audiological measures. The observation
that these improvements were stable for more than two months after
the end of the one month therapy is encouraging.”
Researchers at the University Hospital Antwerp, Belgium, and
MicroTransponder Inc. also contributed to the study. A larger study
involving four different centres will soon begin in the United