Implanted Thoughts

From the article, "FDA Panel Backs Implant To Counter Depression":

The device has been used in the United States since 1997 to control epileptic seizures. The manufacturer, Cyberonics Inc. of Houston, hopes to expand its market: Fifteen to 25 percent of the 19 million Americans with depression may not respond to available treatments, Rush said.

The implant involves connecting a wire to the left vagus nerve in the side of the neck; a battery is implanted high in the left chest or under the armpit, and the amount of current can be regulated externally. Typically, the implant sends a 30-second pulse of current followed by a five-minute pause, 24 hours a day.

Karmen McGuffee of Garland, Tex., told the panel she had tried virtually every antidepressant drug on the market before getting the device. Improvement came within weeks, she said.

"My mother said she wasn't looking into the eyes of a dead person anymore," she said. When people asked why she was willing to get an implant, she replied, "I had nothing to lose" …

… The panelists mostly agreed that the data presented by Cyberonics had problems but were swayed by the lack of alternative treatments and the evidence that the device is generally safe, based on its widespread use to reduce epileptic seizures.

Cyberonics' central study was a randomized trial involving 221 patients. All received implants, but the power was turned on for only half the group.

Of 111 patients getting stimulation, 17 showed an improvement of at least 50 percent on a psychiatric scale of depression after 12 weeks. Of 110 patients getting "sham" treatment, only 10 showed similar improvement. The difference between the groups was not statistically significant, however.