Cure for tinnitus?

London: Scientists claim to have come up with a potential cure for tinnitus -- a hand-held, sound-wave machine which they say can relieve ringing in ears that often drives victims to despair.

Tinnitus currently has no cure, and treatments range from relaxation techniques to cope with the associated anxiety, to sound therapy where sufferers are taught to "tune out" noise.

Now, scientists say they have another weapon, It`s a hand-held ultrasound device that is placed behind the ear for one minute. The gadget is held against the skull behind the ear, and then emits a high frequency signal.

It`s designed to give temporary relief, and is currently being used in trials on 500 people.

Previous trials show 71 per cent of people experience immediate relief. Exactly how it works is unclear, but its developers believe the energy waves stimulate the auditory nerve, responsible for detecting sound, and the signals from this nerve "distract" the brain from the tinnitus noises.

Tinnitus is caused by damage to the complex auditory pathways in the ears and brain.

Normally, sound passes from the outer ear through the middle ear and on to the inner ear, which contains the auditory nerve and the cochlea -- a coiled, spiral tube with a large number of sensitive hair cells.

If the cochlea becomes damaged, the auditory nerve will reduce the information it sends to the brain. To compensate, the brain tries to "seek out" signals from the areas of the cochlea still working. These signals are over-represented in the brain, causing the sounds of tinnitus.

In older people, tinnitus is often caused by natural hearing loss, which makes the nerves less sensitive. Other causes include a build-up of ear wax, infection, a perforated ear drum or a head injury.