Inside the Science of an Amazing New Surgery Called Deep Brain Stimulation | Innovation | Smithsonian
A neurosurgeon’s view during a brain operation: The head is held in place and covered with an adhesive drape containing iodine, which prevents infections and explains the orange tint. (Bob Croslin)

Inside the Science of an Amazing New Surgery Called Deep Brain Stimulation

The most futuristic medical treatment ever imagined is now a reality

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Like most people in need of major surgery, Rodney Haning, a retired telecommunications project manager and avid golfer, has a few questions for his doctors. He wonders, for example, exactly how the planned treatment is going to alleviate his condition, a severe tremor in his left hand that has, among other things, completely messed up his golf game, forcing him to switch from his favorite regular-length putter to a longer model that he steadies against his belly.

“Can anyone tell me why this procedure does what it does?” Haning asks one winter afternoon at UF Health Shands Hospital, at the University of Florida in Gainesville.

“Well,” says Kelly Foote, his neurosurgeon, “we know a lot, but not everything.”

The vague answer doesn’t seem to bother Haning, 67, an affable man who has opted for the elective brain surgery. And it’s hard to fault Foote for not going into greater detail about the underlying science, since he is, at that very moment, boring a hole in Haning’s skull.

“Can you hear the drill?” Foote asks his patient as he presses the stainless steel instrument against bone. When Haning, whose head is immobilized by an elaborate arrangement of medical hardware, asks why it doesn’t hurt to have a dime-size hole drilled in his skull, Foote calmly explains that the skull has no sensory nerve receptors. (The doctors numb his scalp before making the incision.)

The two continue to chat as Foote opens the dura—“It’s the water balloon that your brain lives in,” he says. “It’s sort of like a tough leather, for protection”—and exposes Haning’s brain.

Deep brain stimulation, or DBS, combines neurology, neurosurgery and electrical engineering, and casual conversations in the operating room between doctors and their wide-awake patients are just one of the surprises. The entire scene is an eerie blend of the fantastic and the everyday, like something from the work of Philip K. Dick, who gave us the stories that became Blade Runner and Total Recall. During surgery, DBS patients are made literally bionic. Tiny electrodes are implanted in their brains (powered by battery packs sewn into their chests) to deliver a weak but constant electric current that reduces or eliminates their symptoms. DBS can improve a shaky putting stroke; it can also help the disabled walk and the psychologically tormented find peace.

During surgery, which typically takes about three hours, the scalp near the small incision site is held open with a retractor, exposing the skull. (Bob Croslin)
A neurosurgeon’s view during a brain operation: The head is held in place and covered with an adhesive drape containing iodine, which prevents infections and explains the orange tint. (Bob Croslin)
Each brain is different. Michael Okun, left, and Kelly Foote rely on sophisticated imaging and microelectrode data to select a path to the faulty circuit. (Bob Croslin)
With a tip the diameter of a human hair, this microelectrode listens in on chattering neurons, providing feedback so that doctors can make adjustments before placing an implant. (Bob Croslin)
With the electrode in place, Haning draws a smoother spiral. (Bob Croslin)
Before the operation, a head ring is attached to the patient and the brain is imaged, helping the doctors determine electrode placement. (Bob Croslin)
Okun asks the patient, Rodney Haning, to perform various motor tasks during the operation. (Bob Croslin)
Rodney Haning draws a spiral on a clipboard with his left hand, demonstrating that the brain stimulation suppresses his tremor. (Bob Croslin)
The microelectrode in CT scans. (Bob Croslin)
With imaging and mapping software, the doctors run through the surgery virtually before implanting a permanent electrode. (Courtesy Dr. Kelly Foote)

More than 100,000 people around the world have undergone DBS since it was first approved, in the 1990s, for the treatment of movement disorders. Today, besides providing relief for people with Parkinson’s disease, dystonia (characterized by involuntary muscle contractions) and essential tremor (Haning’s problem), DBS has been shown to be effective against Tourette’s syndrome, with its characteristic tics, and obsessive-compulsive disorder. Add to that a wave of ongoing research into DBS’s promise as a treatment for post-traumatic stress disorder and other neuropsychiatric conditions, as well as early signs that it may improve memory in Alzheimer’s patients.

Suddenly it’s one of the most exciting treatments in modern medicine. With seemingly millions of potential DBS patients, it’s easy to imagine a future where brain implants may become as common as hip replacements.

As co-directors of the UF Center for Movement Disorders and Neurorestoration, Foote and neurologist Michael Okun are at the forefront of the DBS field, refining operating techniques and establishing a rigorous standard of care that attracts patients from around the country and the world. Since teaming up at UF in 2002, Okun and Foote have done nearly 1,000 DBS procedures together and grown their two-man effort into an interdisciplinary program with more than 40 staffers, including eight neurologists, a psychiatrist, a neuropsychologist and physical, speech and occupational therapists. The treatment, for patients whose symptoms aren’t sufficiently controlled by medication, carries the usual risks associated with neurosurgery, including stroke and infection. Side effects range from headaches to speech and memory problems, and, in some cases, seizures. But Okun says more than 90 percent of their patients rate themselves as “much improved” or “very much improved” on standard postoperative outcome scales.

In the 12 years since they joined forces, Okun and Foote have seen DBS evolve, in Okun’s words, “from crazy, to kind of cool but not completely accepted, to accepted.” Okun, 42, recalls: “When I first got hired here, my chief said to me, ‘You’re a nice kid, you’re a polite kid, but don’t embarrass us.’”

Together, Okun and Foote breached the wall that has forever separated neurology and neurosurgery—blew it to smithereens, actually—and formed a partnership that defies tradition as it advances the science of DBS. While it might sound logical to the layman—of course neurology and neurosurgery go together—it’s hard to overstate how very differently the two disciplines have been practiced. And perceived. Foote, 48, whose smile comes easily and often, captures the old thinking with an old joke: “What’s the difference between neurology and neurosurgery? Well, both types of doctor treat people with disorders of the central nervous system. And if there’s something you can do about it, it’s neuro­surgery. If there’s nothing you can do about it, it’s neurology.’”

It’s all too true that neurologists have had to deal with more than their share of incurable conditions with unknown causes. Multiple sclerosis, Lou Gehrig’s disease, myasthenia gravis. The list goes on, and watching Okun at work in the OR during a DBS procedure, it’s as if he’s out to make up for all those decades of frustration in the specialty he loves. “Mike has a very surgical personality,” says Foote. “And I am much more of a neurologist than most neurosurgeons.”

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Okun and Foote met as residents at UF in the 1990s. Foote grew up in Salt Lake City and was in high school there when, in 1982, the town produced the biggest medical story in the world at the time—the saga of Barney Clark, the first human recipient of a permanent artificial heart, the Jarvik 7. The operation was performed at the University of Utah, and though Clark died after 112 days, Foote’s fascination with the case endured. He earned a degree in materials science and engineering at the University of Utah, intending to become an inventor of artificial organs. He entered medical school at Utah, where two things changed his course. First, he realized that biological solutions such as improved anti­rejection therapies, not mechanical organs, were the future of transplant medicine. Second, he did his neurosurgery rotation and saw the brain for the first time. “What could be more fascinating than the brain?” he asks.

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