HOUSTON -- The pacemaker is a common medical tool to help heart patients, but it has benefits for other patients as well.

Doctors said that a pacemaker-type device is breathing new life into the lives of Parkinson's disease patients, who often feel like a prisoner in their own bodies.

PARKINSON'S DISEASE Symptoms RESOURCES Parkinson's Disease Foundation American Parkinson Disease Association MedlinePlus Michael J. Fox Foundation

Mark Gaul was diagnosed with Parkinson's disease 10 years ago. After taking medication for years, the side effects were getting worse and simple tasks became harder to do.

"It was really fine-motor movement like writing my name, brushing my teeth, stuff like that (that I had trouble with)," Gaul said.

He decided to take a chance on a new surgery as an alternative to medicine. Doctors implanted a pacemaker-type device, called the Activa Tremor Control System, in Gaul's chest. A wire from the device is then connected to the area of his brain that has been affected by the disease.

Once it is calibrated, the Activa Tremor Control System sends stimulation to the brain.

"It's not anything you can feel. It's not a shock per se, but it's an electrical stimulation of the cells," said Dr. Greg Bonnen, with Memorial Hermann Hospital in Houston.

A month after the surgery, Gaul said the results are amazing.

"I'm back in control. That sums it up -- back in control," Gaul said. "To be honest, I couldn't stop grinning after I had it turned on. I was almost normal."

People with Parkinson's disease live with deteriorating motor skills, causing them to have extreme swings in movement control or tremors.

Actor Michael J. Fox announced that he was diagnosed with Parkinson's disease in 1991, and he has become an advocate to find a cure.

Doctors said that the Activa Tremor Control System provides relief, but it is not a cure. And the procedure does not work for all Parkinson's patients, according to doctors.

When Gaul turns the device off, his tremors are back within seconds. His balance and ability to walk straight is also affected.

"My balance is severely affected by this. Even though I'm not dizzy, my balance is severely impacted," Gaul said.

The Federal Drug Administration approved the device in November 2002.

Doctors said that it takes about one month after surgery for swelling to go down before the pacemaker can be turned on and calibrated for patients. The shelf life on the pacemaker's batteries is approximately five years, so patients need to undergo another surgery at that time, doctors said.

Approximately 650,000 people in the United States suffer from Parkinson's disease. The average age of onset is 60, according to doctors.

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