She executed a very recognizable one. Tears flooded her eyes.
“It was a miracle to see the change,” she said. “Dr. Halpern told me, ‘That’s where we’ll leave the permanent electrode.’ And they put me back to sleep.”
A machine with a precision arm aided the insertion of the leads at the specified coordinates. Leaving the wires in place, Halpern bandaged up the incision sites.
In a follow-up procedure a few days later, Halpern connected the extensions to a pulse generator. He made a 2½-inch incision on one side of Benedix’s chest and placed the pulse generator below her collarbone. Using a device to tunnel beneath her skin, he threaded the reserve coils of exposed wire on her head past her ears, down the back of her neck and over her shoulders to her chest, where he connected the wires to the pulse generator.
The two operations took about three hours in all.
Benedix returned to Stanford Health Care a month later. Movement-disorder specialist Traci Hornbeck, a physician assistant in Stanford’s Department of Neurosurgery who’s been programming DBS devices since 2004, activated the device. Ratcheting up the current in small steps, Hornbeck adjusted the pulse volume to provide maximum tremor inhibition without triggering side effects such as slurred speech, sensory disturbances, involuntary muscle contractions or balance problems.
The effect kicked in right away. Hornbeck estimates that activating the device reduced Benedix’s tremor by 90%.
“It was almost like being in the dark and having a light switched on,” Benedix recalled.
Hornbeck tested Benedix’s ability to draw a straight line and a spiral, sign her name, stretch her arms to the side, apply mascara and bring a cup of water to her mouth.
“Most patients are skeptical,” Hornbeck said. “Often it’s been years since they’ve tried. They say, ‘I can’t do it!’ I say, ‘Yeah, you can.’”
Hornbeck should know. “I always tell patients that I’m part of the tremor tribe,” she said. “I have essential tremor myself.”
Excited, Benedix got on her phone and started texting family members. Typing with that tiny keyboard would have been difficult, if not impossible, just minutes earlier.
“In that moment, I knew that everything in my life was going to change,” Benedix said. “And from that moment on, I’ve become more independent every day.”
Hornbeck gave Benedix a battery charger and a remote control. She can regulate the device settings within limits, optimizing separately for her left and right hands.
“It’s just like your TV — if you need your volume turned up, you just do it,” she said.
Benedix doesn’t expect perfection. She understands that her disease will progress. But her current amplitude is set low; there’s plenty of room left to ramp it up.
“I feel like my life has been handed back to me,” she said. “I only wish I’d done this four years sooner.”