DEVICE: Ampa One System (00860011991205)

Device Description: The Ampa One System is a computerized, electromechanical medical device that produces and delivers non-invasive, magnetic fields to induce electrical currents in brain tissues to target specific regions of the cerebral cortex. The system contains two different coils for targeting different regions of the brain. The L Coil is designed to target the left dorsolateral prefrontal cortex (DLPFC). The M Coil is designed to target the bilateral prefrontal cortex (DMPFC). Both coils are used within the Ampa One System to treat Major Depressive Disorder (MDD) in adult patients who have failed to receive satisfactory improvement from prior antidepressant medication in the current episode. Transcranial magnetic stimulation (TMS) is a non-invasive technique for stimulating brain and neural tissue. The principle of magnetic stimulation is implicit in Faraday's law. The pulses of current are generated with a circuit containing a capacitor connected to the stimulating coil. With the capacitor charged to a certain level, the conducting state will cause the discharging of the capacitor through the coil. A magnetic field is generated proportional to this current. The rapid change in the magnetic field induces a current in conducting materials e.g. the body tissue. If the current induced in the human body is of sufficient amplitude and duration, it will excite neurons.