"She has a good profile," Bailes said of Poe, at the time of her surgery. "She's failed the best surgery that we know of, which is gastric surgery. ... So I think it is the best chance for them, for her."
Skeptics may wonder if deep brain stimulation is a drastic medical treatment for a behavioral problem, but Bailes believes "there is a medical issue of obesity."
"I believe that many people have done everything they can," he said. "And maybe there's some predisposition. Maybe there's some effect that the brain cannot control exactly what we consume."
There are risks associated with the surgery -- from infection and hemorrhaging, and in the most extreme cases (less than 1 percent) paralysis or death. Bailes said the FDA had been "appropriately scrutinizing" the study.
"For some, it may seem radical that electrodes should be put in the brain, that someone should be doing brain surgery for obesity. But I think we've gotten through that and we are very happy to be able to do the first series of patients here, looking at the effects and possible benefits," Bailes said.
"This is a frontier of medicine, a frontier of neurosurgery, a frontier of neurological disease, to be able to generate tiny pulses of electricity in these deep nuclei of the brain, and to see what effect they may have on behavior, including in this case the behavior of eating and the issue of uncontrolled appetite,'' he said.
Since there are no pain receptors in the brain, Poe's scalp was prepped with a topical anesthetic. She was awake throughout the surgery.
"I'm excited about being awake. I want to be awake," she said, before her surgery. "Because if I'm awake, I'll know everything that's going on."
Neurosurgeons, Dr. Michael Oh and Dr. Donald Whiting drilled about 10 centimeters into Poe's brain, on both hemispheres, through a pathway of tissue that does not affect other functions. When they reached a point in the hypothalamus, which controls the stomach, a wire was introduced that would ultimately carry an electrical pulse. The plan was to alter the level of electricity that's generated by that region naturally, thereby giving Poe the sensation of feeling full.
Dr. Oh followed the surgery on a computer, which helped the surgeons find the point at which they'd introduce electrodes.
"Although we are applying this technology for obesity, there are certainly many more possibilities in the near future that are going to be available for people with many neurodegenerative disorders," Oh said.
To some extent, the surgeons are able to evaluate patients' reactions during an awake surgery and talk to them.
"During this procedure, when we have the electrode in this target, we will be asking her about stimulation-induced responses, whether she has a feeling of hunger whether she has any memory responses," Oh explained.
During the surgery, the surgeons can actually provoke a reaction to this electrical current and control the current by adjusting the amount of electricity applied.
Once they get a successful response, doctors "implant a permanent generator, and they have this constant electrical current to that part of the brain," Oh said.
Poe said the procedure didn't hurt but found the stabilization device the doctors put on her head uncomfortable. "It's just real tight," she said. "Like your head is in a vice."