Electrical stimulation of auditory cortex in brain, using a patch placed under the scalp, could reduce ringing in ears.
A pilot study at Minnesota, US, shows that electrical stimulation of auditory cortex in brain, using a patch placed under the scalp, could reduce ringing in ears.
Although the problem, known as tinnitus, can be triggered by many underlying problems, from earwax to high blood pressure, in most cases the cause is unknown.
It's estimated that up to a third of all adults experience tinnitus at some time, and that seven per cent of men and women will visit their doctor with the problem. It can have a severe impact on the quality of life.
Although there have been many treatments suggested and tried, including various herbs, distracting devices, anti-depressants and behaviour therapy, no cure has been found.
In the latest study, a stimulator device about the size of a pack of cards is implanted in a pocket created by the surgeon in the upper chest area. The electrical impulses it generates travel through a lead tunnelled under the skin to an electrode patch that has been surgically placed over the dura, the protective membrane that covers the brain's surface.
A handheld remote control device allows doctors and patients to turn the device on and off and adjust stimulation levels.
Results from the study with eight patients showed that all improved at the end of 12 weeks. Two patients experienced sustained reduction of tinnitus and six patients had short periods of total tinnitus suppression, reports the Telegraph newspaper from London.
Two of the patients suffered from moderate to severe depression as a result of their condition; both improved to mild or minimal depression following the cortical stimulation. Most of the patients had periods where their tinnitus was alleviated, despite having had constant tinnitus for many years.
How it works is not clear and further studies are being planned, but other research shows that the same kind of stimulation above other areas of the brain can reduce the symptoms of depression. One theory is that the stimulation interferes with signals travelling between nerve cells in the auditory cortex.
"Many sufferers become frustrated by the lack of treatment options and are often told nothing can be done," says Dr Alan Levy, chief executive of device developers Northstar Neuroscience. "Electrical stimulation of the cortex may offer additional hope."
When the treatment could become more widely available is not yet known.