Repetitive transcranial magnetic stimulator with controllable pulse parameters

Area of Science:

• Neuroscience
• Biomedical Engineering
• Medical Devices

Background:

• Transcranial magnetic stimulation (TMS) effectiveness is linked to pulse characteristics.
• Current TMS devices have limited control over pulse parameters.
• Optimizing TMS requires precise manipulation of electric field pulse properties.

Purpose of the Study:

• To introduce a novel controllable pulse parameter TMS (cTMS) device.
• To demonstrate the device's capability for generating adjustable electric field pulses.
• To evaluate the impact of cTMS on energy consumption and coil heating compared to conventional TMS.

Main Methods:

• Development of a novel TMS device using a circuit with two energy storage capacitors and two IGBT modules.
• Generation of near-rectangular electric field pulses with adjustable phase number, polarity, duration, and amplitude.
• Measurement of energy dissipation, coil heating, and pulse parameter variability.

Main Results:

• The cTMS device produces electric field pulses with adjustable phase widths (10-310 µs) and amplitude ratios (1-56).
• Energy dissipation reduced by up to 82% (monophasic) and 57% (biphasic).
• Coil heating decreased by up to 33% (monophasic) and 41% (biphasic).
• Repetitive TMS trains up to 50 Hz showed minimal pulse variability (<1.7% amplitude, <1% width).

Conclusions:

• The cTMS device offers unprecedented control over TMS pulse parameters.
• Reduced energy consumption and coil heating enhance safety and efficiency.
• This technology promises to advance TMS research and potential clinical applications.