Deep brain stimulation benefits people with Parkinson's, essential tremor

Tom Keilen couldn't grab a glass of water without spilling it all over himself. Plagued with uncontrollable tremors at just 57 years old, the Michigan resident was fighting a battle against an aggressive case of Parkinson's disease.

He couldn't work at his job as a plastering contractor. His arms would flail uncontrollably, and the medications usually prescribed for Parkinson's didn't help enough.

Keilen sought help at the University of Michigan, where after an extensive assessment, he underwent a deep brain stimulation surgery in which a thin wire electrode is placed precisely in the brain and produces electrical signals. Keilen's surgery, part of U-M's Surgical Therapies Improving Movement (STIM) program, was successful in almost eliminating the tremors.

"If it weren't for the deep brain stimulation, I wouldn't be sitting here. My arms would be flying. I'd be sitting in a nursing home," says Keilen, who adds he bought a dream car after learning he'd be undergoing the procedure.

"I'm still able to drive my hot rod. That's my reward."

Movement disorders like Parkinson's and essential tremors are a lot more common than many people think, says Kelvin Chou, M.D., co-director of the STIM program and associate professor in U-M's Department of Neurology.

Up to 5 percent of the general population is affected by essential tremors and about one in 1,000 have Parkinson's. The Parkinson's numbers are much higher for those over 60 — one in 100 have the disease.

"Movement disorders can certainly affect someone's quality of life, especially those with tremors. In someone living with essential tremor, the tremors are most prominent when the person is using their hands. Eating, writing, those types of activities will be affected," says Chou. "Things we take for granted like signing a check, shaving or applying makeup can be very, very difficult for people with essential tremor to do."

Tremors from Parkinson's disease do not usually affect people's activities, unless the disease is very severe, as in Keilen's case. However, many people are embarrassed by it and don't go out to restaurants or socialize.

Medications can be effective for about 70 percent of patients with essential tremor, and can work well for those with Parkinson's. But for many Parkinson's patients, the symptoms begin to worsen or don't respond as well to medication over time.

"When that starts to happen, when a Parkinson's patient is forced to take medications every couple of hours just to keep themselves going, or if medications don't help an essential tremor, that's when deep brain stimulation may be an option," Chou says.

Patients see dramatic, life-transforming changes after the deep brain stimulation. Keilen says it was like a switch that turned off his tremors.

"Not only do we have the anecdotal evidence of patients telling us that their lives have been changed, there have been careful studies comparing deep brain stimulation to using medication alone," says Parag Patil, M.D., Ph.D., co-director of U-M's STIM program and assistant professor of neurosurgery.

"These studies, particularly in Parkinson's disease, have shown that the quality of life improvements of carefully chosen patients treated with deep brain stimulation are much better than patients treated with medication alone."

In the procedure, electrodes are placed in the brain while the patient is awake, and the patient's reactions are tested in the operating room. The patient then is put under anesthesia and surgeons insert a thin, flexible wire and a pulse generator placed in the chest. The wire allows electrical signals to target areas of the brain.

"Deep brain stimulation is like a pacemaker. The wire goes in and it creates an electrical signal that acts kind of like a metronome to keep the brain in order," Patil says.

Patil says at U-M there's a team of experts who spend a lot of time assessing whether a patient is a good candidate for deep brain stimulation. That multi-disciplinary team includes a neurosurgeon, neurologist, speech pathologist and social worker. In addition, there is a neuropsychologist, who specializes in understanding thinking patterns associated with neurologic diseases. Patients also have access to physical therapists and psychiatrists.

"It's a real advantage to have this significant breadth of expertise. We can look beyond just the neurologic side and include the psychiatric issues and the patients' home life through social work. It provides a very rich therapy," Patil says.

When U-M started its program five years ago, about four or five patients were treated with deep brain stimulation each year. That's now up to about 30 patients each year and Patil says there are many people in Michigan and all over the world who could benefit from the surgery.

"Our goal is to increase awareness through educational programs and outreach to community physicians so that appropriate patients can get this really beneficial therapy," Patil says.