Adaptable Dual-Tuned Optically Controlled on-Coil RF Power Amplifier for MRI

Area of Science:

• Medical Imaging
• Radiofrequency Engineering
• Physics

Background:

• Current multinuclear Magnetic Resonance Imaging (MRI) systems require complex hardware for simultaneous or sequential imaging of different nuclei.
• Implementing adaptable radiofrequency power amplifiers (RFPAs) directly on transmit coils can simplify hardware and improve efficiency.

Purpose of the Study:

• To present an adaptable, optically controlled RFPA for direct integration onto 7 Tesla MRI transmit coils.
• To demonstrate the amplifier's capability for dual-tuned operation at proton (¹H) and various X-nuclei frequencies.

Main Methods:

• Development of an optically controlled RFPA with an integrated voltage-modulated inductor in the gate driver circuit.
• Automated tuning mechanism to adapt the amplifier's operating frequency.
• Bench and in-vivo MRI data acquisition using the dual-tuned on-coil RFPA.

Main Results:

• Successful demonstration of adaptable operation at both ¹H and multiple X-nuclei frequencies for 7T MRI.
• Acquisition of comparable bench and MRI data using the developed dual-tuned RFPA.
• Validation of the automated tuning for seamless frequency adaptation.

Conclusions:

• The adaptable on-coil RFPA offers a simpler, more efficient, and versatile solution for multinuclear multichannel MRI hardware.
• This technology facilitates broader research into MRI-detectable nuclei, potentially revealing new insights into healthy and diseased tissues.