In the migraine study, subjects place the 3-pound device at the back of the head when they feel a headache beginning. The press of a button sends two high-frequency waves into the brain. The lead investigator in the trial, Richard Lipton, a neurologist at Albert Einstein College of Medicine in the Bronx, says the pulses act as a kind of "reset" switch that stops the electrical storm causing the migraine.
If the FDA does give approval, TMS could change the treatment landscape. Lipton estimates that "millions" of migraine sufferers -- there are 35 million in the U.S. -- could eventually use the Neuralieve device.
Psychiatrist Scott Aaronson, director of research at the Sheppard and Enoch Pratt Hospital, estimates that a third of depression patients don't improve with current therapies -- and may be helped by TMS.
"We're likely to be able to treat people we haven't been able to help before," says Aaronson, who was one of the investigators in the Neuronetics trial.
Most depression patients are treated with drugs such as Prozac or Effexor; these medicines often don't work, and more than half of patients taking them suffer serious side effects, including drowsiness, weight gain and loss of libido.
For those who don't improve or can't tolerate the drugs, there are a variety of treatments that directly target the brain. The most effective is electroconvulsive therapy, or ECT, which works about two-thirds of the time. Although ECT is much safer than it was in its heyday 60 years ago, it still poses real risks -- particularly short-term memory loss.
Two other electrical therapies are sometimes used: DBS (for deep brain stimulation) and VNS (for vagus nerve stimulation). Both require surgery for permanent implantation of electrodes.
TMS, by contrast, is noninvasive and has almost no side effects. Some patients feel an uncomfortable tingling in their scalp during the first few sessions, O'Reardon says. But because it stimulates a specific brain area rather than the whole body, as drugs do, or the whole brain, as ECT does, TMS has far fewer unintended consequences.
TMS does have disadvantages. It is expensive: A round of treatment typically runs between $5,000 and $7,000. Even if the FDA approves it, insurance companies may be reluctant to cover the cost. And it can take time: an hour a day for several weeks for treatment of depression. Some worry that the improvements produced by TMS may not last more than a few days or weeks.
But many researchers -- and patients like Zatuchni -- say TMS patients may need repeated treatment to keep brain circuits working properly.
Zatuchni goes for such sessions every two weeks, which, he says, keep him stable and happy. Since his TMS treatment began, he has begun work on two novels; he's almost finished one and has hooked up with an agent.
"I just wish I had gotten it 15 years ago."
david.kohn@baltsun.com
