Martha Buckalew had a great life. She traveled with her husband, drove her golf cart to garage sales in Sun City, played bridge with friends.
Then she was diagnosed with Parkinson's disease. Her gait slowed and stiffened. Her hands shook so badly she couldn't hold a pen. She fainted at church.
In December, Buckalew was wheeled into an operating room. A neurosurgeon drilled two holes into her skull, inserted electrodes in her brain and sent her back to a better life.
The treatment is deep-brain-stimulation therapy, or DBS, which uses electrical pulses to quiet her tremors. It has been used as a last-resort medical treatment since 1997 for people with certain movement disorders.
Now, doctors hope the therapy can treat an array of ailments, from easing depression to controlling morbid obesity.
As the medical community learns more about the brain's physiology, the pacemaker-like device has far-reaching potential.
Array of treatments
Researchers expanded the scope of deep brain stimulation beyond movement disorders when the U.S. Food and Drug Administration last year approved its limited use for obsessive-compulsive disorder.
Now, about 30 clinical trials are under way to research the therapy's possible use to treat about a dozen disorders.
Some trials are for relatively rare conditions such as Tourette's syndrome and Huntington's disease. Others are for more familiar afflictions such as epilepsy, depression and obesity. A clinical trial also is under way in Canada to study whether the treatment can improve memory in Alzheimer's patients.
Deep brain stimulation works on the principle that the brain controls all the activities of the body. Find the right neurological pathway, and you can adjust the body's actions.
Dr. Donald Whiting is leading a clinical trial in hopes of combating morbid obesity: being 100 pounds or more overweight.
Electrodes were implanted a year ago in three patients who had failed to lose weight by traditional measures, including gastric bypass surgery, said Whiting, a neurologist at West Virginia University Hospital. The trial is expected to wrap up by early 2012.
"At this point we have been able to kind of get rid of their urge to eat," Whiting said. "They seem to be eating less, but it's harder to document any metabolic changes. It's promising but still too early to say if it's effective enough."
'Some real benefits'
In 2006, Diane Hire of Ohio was one of the first patients in a pilot study to undergo the therapy for chronic depression.
"I was severely depressed for 20 years, to the point in the last 10 years I could hardly function on my own," the 56-year-old said. She attempted suicide three times. "I could not work and was put on disability. I would get out of bed in the morning and say, 'Oh, good, only 16 hours before I can go to bed again.' "
She tried 20 medications, psychotherapy and electroconvulsive therapy. Then she tried deep brain stimulation.
"I am a completely different person," said Hire, who still takes Prozac and Wellbutrin but hopes to be eventually weaned off the psychotropic drugs. "I wake up happy and ready to face the day."
Cleveland Clinic psychiatrist Donald Malone is the lead investigator in the use of deep brain stimulation for treatment-resistant depression. A clinical trial with 30 volunteers will conclude in two years. He also oversaw the pilot trial that involved Hire.
"The preliminary findings demonstrate some real benefits in patients who don't get better in any other way," Malone said. "Patients enrolled in these trials are not the run-of-the-mill average depression patient. For the most part, the odds of them responding to different medications or therapies are very, very small."
Some physicians in the U.S. and Europe are trying the therapy for chronic pain.
Dr. Virgilio Evidente of the Mayo Clinic in Scottsdale has performed the therapy on two patients with severe, recurring headaches.
Chronic head pain that may benefit from the therapy includes cluster headaches and headaches that bring stabbing pain for only a few seconds but occur hundreds of times a day.
Evidente said the therapy anecdotally has been effective in patients with failed-back syndrome, which is persistent pain because of back surgery.
He said certain patients respond well. But the therapy doesn't work for everyone.
"We don't know why," Evidente said. "Obviously, pain syndromes are not all the same."
The surgery
Dr. David Pootrakul has become a local expert on the therapy, using it at Banner Boswell Medical Center on more than 70 patients with movement disorders such as dystonia and Parkinson's.
In December, with representatives from Medtronic, the manufacturer of the device, providing technical support, he performed the delicate procedure on Buckalew.
Buckalew was awake, her shaven scalp numbed by anesthesia, when Pootrakul drilled two dime-size holes into her skull.
A thin electrode, guided by a metal frame screwed into Buckalew's head, was slowly inserted through a hole drilled into the right side of her brain. The pathway is charted by a computerized image-guidance system.
Once Pootrakul was comfortable that the electrode hit the target site, he performed tests. He asked Buckalew to tap her fingers together and to repeat "sunny day in Sun City."
Satisfied that the electrode's placement helped to reduce the tremors, Pootrakul repeated the surgical procedure on the left side of Buckalew's brain.
A week later, Buckalew returned for part two of her surgery, this time as an outpatient. Pootrakul implanted a neurostimulator below her collarbone and connected it to the electrodes in her brain through a thin wire that tunnels under her scalp and neck.
A week after the surgery, Buckalew went to her neurologist, who turned on the neurostimulator, a stopwatch-size box that houses a battery and microchip.
With more than 60,000 possible settings for stimulating the brain, it will take multiple office visits to get the right programming. The physician makes the adjustments on a device similar to a TV remote control.
It may take months before doctors determine how much the therapy improves Buckalew's medical condition. Her hands don't tremble, her balance is better and she can walk without holding onto her husband. She has resumed the everyday chores that had eluded her, such as cooking and ironing. Better yet, she is no longer a shut-in.
"I am able to get around better," Buckalew, 75, said. But she would like to rely a lot less on medication.
Pootrakul is the only surgeon performing deep brain stimulation at Banner Boswell. The Sun City hospital, Mayo Clinic and St. Joseph's Hospital and Medical Center are the only medical facilities in the Phoenix area that offer the procedure.
More than 75,000 people worldwide have undergone the surgery, according to Medtronic Inc., the only company approved by the FDA to sell the system in the United States.
A last resort
Deep brain stimulation is a last-resort treatment, used only in patients whose medications and other remedies stop working or when the side effects from treatments do more harm than good.
Brain surgery carries risks of cranial bleeding, paralysis, coma and death. If a brain infection develops, it could lead to bacterial meningitis, a swelling and irritation of the membranes covering the brain and spinal cord that can cause brain damage or hearing loss.
And the devices themselves can pose complications. Double vision and numbness can emerge. Some patients report jolting or shocking sensations sparked by the device's electrical charge.
Sometimes, symptoms of the disease worsen temporarily, according to Medtronic officials.
Another drawback to the therapy is its price tag. At Banner Boswell, if a patient doesn't have insurance or qualify for the state's health insurance for the poor, the procedure costs about $128,000. And for uses that haven't been FDA-approved, insurance generally won't cover the therapy's cost, according to Evidente of Mayo Clinic.
Still, brain stimulation therapy has advantages.
Unlike previous surgeries to control Parkinson's symptoms, the therapy doesn't damage brain tissue.
The neurostimulator can be programmed to adjust to a patient's changing medical condition.
And the procedure is reversible, allowing the device to be removed if better treatments become available.
The therapy doesn't cure a patient's condition but can control the symptoms, enabling patients to reduce their medication by half or even more, Pootrakul said.
What's next
Medtronic has the monopoly on brain-stimulation devices in the United States.
However, several companies are emerging on the horizon. St. Jude Medical has received approval in Europe and Australia to sell its stimulator device. And NeuroPace is focusing its foray into the market with a similar stimulation device for epilepsy.
Medical experts said the technology has nearly limitless potential to ease brain-related disorders, once physicians know which part of the cerebrum to target.
"There's no question as we learn more about the science of the brain's physiology, more people realistically can benefit from neuromodification of the brain," said Dr. Michael Schulder of the American Association of Neurological Surgeons.
Schulder said the therapy could be used in the far-off future for conditions such as hypertension and diabetes. But careful study is required.
It's not as if 20 million Americans with major weight problems or psychological issues will have implants to control their conditions within five years, he said.
First, help is ahead for those suffering from Alzheimer's, depression and chronic pain.
"Over the next 10 years, if we can make a dent in those conditions with DBS, we will really have done a great service to the world," Schulder said.
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