Shock and Awe

A polymer mask used during brain-imaging scans Colleen Kelley

Worldwide, there are only four well- documented cases of successful DBS for depression patients. Those patients were implanted at the University of Toronto, where, in 2005, researchers reported that the results were "striking": Of six patients who underwent the procedure, four experienced a significant improvement within six months. Medtronic, the company that makes the deep-brain stimulator, reported that about 30 more depressed people have been implanted with the device in the U.S., although the results of those studies have not yet been widely published. Currently, the FDA and an ethics committee are reviewing a DBS study proposal by the brain-stimulation lab, where Kelley hopes to receive the $60,000 to $75,000 surgery.

In addition to depression, DBS has also produced successful results for Tourette patients. Probably the example closest to home of a post-DBS patient that Kelley can look to is Steve Blackman, a Monticello, New York, resident who underwent the surgery at Yale to control a severe case of Tourette syndrome in 2004. He was the second person in the world to get DBS for Tourette. His case provides a fascinating link between the world of movement disorders and psychiatric disorders, since Tourette can arguably be categorized as both.

Blackman was diagnosed with Tourette at age three. He used to have vocal tics that were sometimes nonstop. "I was screaming, I was yelling, I was just totally out of control," he recalled. Now the vocal tics have disappeared; what persists—although at a much-reduced rate—are the physical tics. At irregular intervals, Blackman's head snaps forward forcefully and then back, as if he's in an invisible car crash over and over again. He has chronic whiplash and permanent spinal damage from the tics. He uses a leg brace and cane to get around, and has had several surgeries to relieve the neck and back pain caused by the tics. Before the DBS treatment, he had up to 2,000 of these neck-jarring tics each day; now he usually has fewer than 100. "It's saved my life," Blackman said.

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Since childhood, he has experienced only a brief period when he was completely tic-free—just after the DBS surgery in 2004. For a few weeks immediately after the device was implanted, but before it was actually turned on, Blackman's tics completely disappeared. His doctors were stunned, since he wasn't receiving any electrical stimulation yet. "It is still not understood exactly how DBS works," said Dr. Alain C.J. de Lotbiniere, Blackman's neurologist.

On a sunny August afternoon, when Blackman came to see de Lotbiniere in his White Plains office, it was apparent that much of DBS is still in the trial-and-error stage. As in most of the brain-stimulation studies, the device's manufacturer works closely with researchers to develop and test the stimulators. Blackman's brain stimulator was made by Medtronic, and a representative of the company attended the doctor's appointment to help de Lotbiniere figure out why, over the last month, Blackman's tics had gotten worse. Despite the combined total of eight fancy acronyms after their names and decades of experience, both admitted that they still don't know exactly how DBS works, or why, in this instance, it was faltering. After they ruled out a flagging battery in the stimulator, the tweaking began.

Blackman sat in the middle of the office, with de Lotbiniere and the Medtronic rep standing over him. The duo conferred over a "physician programmer," a touch-screen remote control for the deep-brain stimulator that looks like an oversize Palm Pilot. Rather than controlling a calendar, however, this programmer controls the electricity going into Blackman's brain. Press a button and the voltage goes up; touch another and the pulse width goes down. The Medtronic rep directed the doctor through multiple choices on the tiny screen. They tweaked and debated, then announced that they had turned up the voltage.

"Is anything happening?" de Lotbiniere asked.

"I can't open my right eye," Blackman said. "Is my eye open?" He grimaced as his neck and head snapped forward uncontrollably.

The settings were adjusted again.

"Whoa! I don't know what you're doing, but I feel something—I don't feel good . . . I'm having a lot of problems moving my eyes. My actual eyeball is hard to move," Blackman told them.

A final tweak, and de Lotbiniere and the Medtronic rep declared the adjustment complete. They had changed the width and frequency of the electrical pulses and amped up the voltage. Meanwhile, Blackman had regained most of his eye movement (apparently, his electrodes are implanted near an area of the brain that controls this). If the adjustment doesn't minimize his tics, he may have another round of surgery to get an additional two electrodes implanted in a different part of the brain.

"It's hard to accept that this is the best we can do," said Dr. James Leckman, another of Blackman's doctors and a Tourette specialist at Yale who has collaborated with the New York brain-stimulation lab. "He's a good example of how ignorant we still are."

Researchers at the lab will look into prior research on Blackman and the Toronto patients to replicate and improve DBS for depressed patients. Kelley has been anxiously awaiting her chance to enroll in that study.