Experimental surgery pays off

by Kelly Wittman

Bob Zgonc served as an officer of the Minnesota Highway Patrol for 28 years. He was an outdoorsman who loved to hunt, fish and walk in the woods, but that was before the tremors, shakes and muscle rigidity of Parkinson’s Disease forced him into retirement.
Almost 1.5 million Americans suffer from the effects of Parkinson’s disease, but two University neurosurgeons, Dr. Robert Maxwell and Dr. Walter Low, have had success treating Zgonc by implanting electrodes into his brain. Zgonc returned home and has been administering stimulation through the electrodes, which he controls with a pocket-sized device.
Zgonc underwent the procedure last October at Fairview-University Medical Center — then the University Hospital — and was the first Minnesotan and the third person in the nation to have the operation.
Now, six months after Zgonc’s surgery, Maxwell and Low have declared that the muscle spasms that were plaguing their patient are gone.
“When (Zgonc) turns the device on you can watch the increased tone in his hands and legs melt away within minutes,” Low said. “This could become the major way of treating patients with Parkinson’s when medications prove no longer useful.”
The procedure has led to a renewed life for Zgonc. The tremors and muscle cramps have been all but “knocked out,” Zgonc said. “Most of the days, I’m pretty good. I don’t get bad days like before. No way.”
Where before he couldn’t even walk without help, Zgonc said he is now doing so well that he is living independent of assistance, and his wife is able to go back to work.
The procedure was offered to Zgonc as part of a clinical trial. The University is one of only two institutions approved by the Food and Drug Administration to perform the procedure. The University of Kansas is the other institution authorized to conduct the operation, and it is where the first surgery of this type was performed in October, 1995.
The procedure involves implanting “a tiny pacemaker for the brain” inside the head, Low said. During the surgery, four electrodes are implanted into the pallidum, located just above the brain stem. The patient is given a local anesthetic to numb the incision, but since the brain has no pain receptors of its own, the patient has no discomfort and remains awake during the whole procedure, he said.
The surgeons can choose which of the four electrodes to stimulate based on how the patient’s muscle spasms and tremors respond to the therapy, Low said. The patient can use the electrodes to stimulate the pallidum throughout the day, allowing the patient to work and play normally.
A new procedure was needed to help Parkinson’s patients because of the disease’s degenerative action on the body, Low said. The effects of Parkinson’s are caused by a loss of nerve cells in the brain that produce the neuro-chemical dopamine.
In early Parkinson’s, the patient can take a drug that stimulates the remaining cells that produce dopamine. But as the disease progresses, there are fewer and fewer of the cells left, and soon the drug becomes ineffective, Low said.
Zgonc said he took medication for the first several years of his battle with Parkinson’s, but that it eventually became ineffective for him.
While there is a loss of some brain nerve cells that produce dopamine, other nerve cells in the same area of the brain become hyper-excitable, Low said. Once the medication has stopped working, a procedure called a pallidotomy is often used. A pallidotomy involves making a slit in the pallidum and cutting away some of the hyperactive cells that cause twitching and spasms.
Zgonc underwent a pallidotomy last year, but the effects of the procedure did not last, and his tremors and muscle cramps returned. He and his doctors decided against performing another pallidotomy. “They didn’t want to do it twice. They thought I might lose my voice,” he said.
Zgonc decided to take a chance on the experimental procedure. “I didn’t have much choice. You don’t when you’re up against a wall.”