Brainsway, a firm building transcranial magnetic stimulation systems (TMS) out of Jerusalem, Israel, just received European approval to market its devices for the treatment of depression. The TMS treatment is likely to be used initially for cases of severe drug resistant depression. But we can envision a day when this technology becomes a mainstream therapeutic option for bipolar disorder and some other psychiatric diseases.
About the technology from Brainsway:
Transcranial magnetic stimulation (TMS) is a noninvasive technique used to apply brief magnetic pulses to the brain. The pulses are administered by passing high currents through an electromagnetic coil placed adjacent to a patient's scalp. The pulses induce an electric field in the underlying brain tissue. When the induced field is above a certain threshold, and is directed in an appropriate orientation relative the brain's neuronal pathways, localized axonal depolarizations are produced, thus activating the neurons in the relevant brain structure.
Standard TMS coils are limited to activation of only cortical brain regions, up to a depth of about 1.5 cm. Hence when treating depression with a standard TMS system, the limbic system, which is related to mood regulation and is generally deeper than 1.5 cm, is only indirectly affected, through secondary processes involving cortical structures, which are directly activated by TMS and then affect the deeper limbic system structures.