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Implant 'switches off' symptoms
of Parkinson's

By Celia Hall, Medical Editor

REVOLUTIONARY surgery which allows people with Parkinson's disease to "switch off" their symptoms is transforming the lives of a handful of patients, but few health authorities will pay for the operation.

Launching the treatment in Britain yesterday, a surgeon described how a probe is implanted deep in the patient's brain. It is attached to electrodes and a neurostimulator, an electronic device similar to a heart pacemaker, which is put under the skin below the patient's shoulder.

The patient "swipes" the neurostimulator with a hand-held magnet and the severe, rhythmic shaking of the body, lack of balance or rigidity - classic Parkinson's symptoms - stop.

The mild electrical stimulation, which is adjusted to suit each patient, blocks the abnormal brain signals which cause the symptoms.

Its advantage over established brain surgery is that no brain tissue is destroyed with a risk of paralysis or damage to eyesight.

Doctors said up to 20,000 people could benefit, but because of the expense fewer than 30 patients in England and Scotland have been fitted with the Activa Parkinson's Control Therapy made by Medtronic, an American-based company.

The implants cost £4,000 and the surgery between £7,000 and £10,000, said Steven Gill, consultant neurosurgeon at the Frenchay Hospital, Bristol. The stimulator needs replacing every five years which would cost another £10,000.

"The news of this treatment is only just getting out. It makes a huge difference to people's lives. Health authorities say the treatment is still experimental but with someone who is badly disabled the social services costs are very high."

Mr Gill said the treatment, developed in Grenoble, France, was suitable for patients in their 30s and 40s - about one in 12 of the 125,000 Parkinson's sufferers in Britain are under 40.

"If you get side-effects, such as mumbled speech, you can reduce the stimulation or switch the machine off altogether."

Mr Gill's technique is to stimulate an area about 3mm in diameter, deep in the brain, called the subthalamic nucleus. This is specifically involved in the control of movement.