University of Iowa staying on cutting edge with deep brain stimulation

IOWA CITY — Parkinson’s disease can be debilitating — with tremors complicating everyday tasks and rigidity leaving patients struggling with balance and general ease of movement.

Treatment for the chronic and progressive neurodegenerative disorder can range from medication, physical therapy, and surgery — including deep brain stimulation, which involves the implantation of electrodes into patient brains.

“We put them in with the intent that they're going to be helpful forever,” University of Iowa Hospitals and Clinics neurosurgeon Jeremy Greenlee told The Gazette.

UIHC began offering the brain stimulating surgery around 2000, a few years after the U.S. Food and Drug Administration in 1997 formally approved its limited use to treat Parkinson’s and essential tremor — a neurological disorder that affects the nervous system and causes rhythmic shaking.

Since that time, the university has conducted more than 600 deep brain stimulation surgeries, according to Greenlee, who’s done many of them. And the hospital recently put out a request for bids from suppliers of deep brain stimulation technology in hopes of keeping its surgical offerings on the cutting edge.

“We always want to be able to offer the latest and the greatest technology and be sure we're pushing the envelope,” Greenlee said.

UIHC uses deep brain stimulation presently on patients with Parkinson’s, essential tremor, and dystonia — a movement disorder causing muscles to contract involuntarily, forcing twisting and other repetitive spasms.

“We’ve also used it for things like obsessive compulsive disorder,” he said. “And we’ve used it for patients with tics — like motor tics. Those are kind of the tried and true proven indications.”

UIHC has not used deep brain stimulation to treat severe depression — a technique that has not yet received FDA approval but is under investigation at other research institutions, like the University of California San Francisco.

“We have inherited some patients who have been implanted in trials elsewhere with depression that get their follow-up care here and battery changes and things like that,” Greenlee said.

Findings into how effective deep brain stimulation can be for patients with depression are mixed, according to Greenlee, who said he’s unclear whether UIHC might in the future tap the neurosurgical technique for mental health treatment or engage in research around that.

“There's been some studies that haven't shown a big benefit for a big series of patients with depression,” he said. “Clearly it helps some. So the challenge is trying to figure out which patients might benefit from it and which patients are less likely to benefit from it.”

More research is needed, according to Greenlee.

“I could see the university being part of studies like that,” he said.

'I’ve had patients in tears’

For use with Parkinson’s patients, according to Greenlee, the neurosurgical option has proved life-changing.

“You actually get to see it in the operating room,” he said. “I've had patients that have had bad tremor for so long, they're used to it. And then we turn it on and they kind of stare at their hand and their hand is really calm, and I've had patients in tears in the operating room.

“The nurses are in tears watching it happen. It's pretty amazing to see.”

The surgery involves three main components, according to Greenlee. One is a pacemaker — similar to a cardiac pacemaker — that generates electrical impulses and is implanted near the chest, under the collar bone. That’s connected to an extension wire that leads from the chest to the scalp.

From there, wires are thread through scalpel incisions to the brain.

The procedure typically is split into two surgeries — the first involves implanting wires into the brain, taking about two hours plus preparation and cleanup time. The second connects those wires to the extension and pacemaker, requiring another hour in surgery, according to Greenlee.

“Usually they’re about 10 days or two weeks apart so the patient recovers from the first surgery,” Greenlee said, describing the procedure as minimally invasive.

“It is a small incision, and obviously any brain operation is considered a major operation,” he said. “But the incisions are small and the recovery is pretty quick.”

And patients feel the benefits almost immediately, he said.

“As soon as you turn the device on, patients notice immediate improvement in their symptoms,” he said. “Which is really pretty eye opening to see and kind of life changing, in a good way, for patients and their families to see.”

The whys behind the procedure’s benefits are somewhat unclear, Greenlee said.

“It's still kind of a mystery of how it works,” he said. “We do know that we're kind of modulating these circuits in the brain, and some brain regions are overactive and some brain regions are underactive because of the disease itself. So the stimulators, generally, reduce activity in the overactive areas, and that helps normalize these circuits.”

The devices are designed to send pulses continually — although some patients have the ability to turn their system on or off or to increase voltage if their tremor worsens. They come in for routine checkups to adjust settings and supplementary medications.

“A lot of these diseases are progressive diseases,” he said. “The disease itself is getting worse. So now we have that luxury of adjusting the settings to try and fight back.”

Independent again

The university, on average, does 65 to 70 deep brain stimulation surgeries — a number that’s been increasing — with about 60 percent involving Parkinson’s disease, 35 percent for essential tremor, and 5 percent for other disorders.

Although other hospitals in Iowa do some deep brain stimulation procedures, Greenlee said UIHC does “the largest volume in the state by far.” That, he said, is helpful to UI investigators interested in researching brain activity in general and better understanding how the brain is structured and how it controls various behaviors.

Greenlee, for example, is studying speech production.

“They have options of participating in studies if they like,” he said or surgery patients. “That's a collaborative effort that we do with people in neurology and neuropsychology and speech to try to understand and document outcomes as well as try to study brain circuits and mechanisms of how the brain does what it does.”

More than a decade ago, Linda Stambaugh — an Illinois woman who would become a UIHC patient — had been forced to leave her job as a corrections officer due to her progressive Parkinson’s symptoms, including tremors and falls.

Upon her arrival at UI, neurologist Teri Thomsen said Stambaugh “shook so violently that she had difficulty doing even the simplest tasks, such as writing her name,” according to UIHC communications.

Stambaugh struggled to walk, and medication wasn’t controlling the symptoms. But she was hesitant to proceed with brain surgery until running into another woman who had just undergone deep brain stimulation.

“She was so encouraging to me,” Stambaugh told the university.

Greenlee operated on her in 2011, and she was independent again within weeks — driving and even returning to work.

“DBS is not a cure,” Greenlee said at the time. “But it’s one tool to manage the symptoms. If the Parkinson’s gets worse over time, the beauty of DBS is that Dr. Thomsen can just turn up the stimulation to improve symptom relief.”

Vanessa Miller covers higher education for The Gazette.

Comments: (319) 339-3158; vanessa.miller@thegazette.com