Electromagnetic depression treatment nears approval

May 28, 2012 | Source: IEEE Spectrum

Deep TMS (transcranial magnetic stimulation) (credit: Brainsway)

Deep transcranial magnetic stimulation (TMS), a new type of brain stimulation device for combating difficult-to-treat cases of major depressive disorder, is likely to break into the large American market soon.

Its maker, Jerusalem-based Brainsway, plans to apply to the U.S. Food and Drug Administration for permission to market the device this month.

The move follows initial results from a large-scale trial of the system, in which 30.4 percent of treated patients went into remission and 36.7 percent showed significant improvement.

Deep TMS uses magnetic fields to stimulate activity in structures deep in the brain. The patient wears a helmet in which powerful, specially designed electromagnets have been carefully positioned. When a pulse of electricity flows through the magnets’ coils, the resulting magnetic field induces current to flow through a portion of the brain.

“The Brainsway coil is more like a shotgun than a rifle,” says Mark S. George, a pioneer of TMS and director of the brain stimulation laboratory at the Medical University of South Carolina, in Charleston. It’s unclear which weapon will be better at fighting depression. A tightly focused stimulation might be best if researchers knew exactly where to target that stimulation, he says, but they don’t.

The 30.4 percent remission rate Brainsway is claiming may not seem like much, especially when 14.5 percent of patients who underwent a sham procedure also recovered, but in the context of antidepressants it is quite good, according to experts.