Frequency-adjustable magnetic field probes

Area of Science:

• Medical Imaging
• Physics

Background:

• Nuclear Magnetic Resonance (NMR) field probes offer potential for improving MR image quality.
• Applications include k-space trajectory calibration and dynamic local field change measurement.

Purpose of the Study:

• Design and construct novel field probes.
• Improve ease of manufacturing and flexibility compared to existing probes.

Main Methods:

• Utilize a novel light-activated resin manufacturing technique for coil assembly and 1H sample encapsulation.
• Integrate orthogonal coils allowing real-time adjustment of proton resonance frequency via a DC-current-controlled B-field modification coil.

Main Results:

• Demonstrated shifting of field probe position by altering Larmor frequency with an integrated micro-coil.
• Achieved frequency modulation of 113 Hz/mA, tested up to 100 mA without visible artifacts.
• Showcased selective off-resonant excitation and comparable gradient impulse response functions to traditional probes.

Conclusions:

• The developed field probes facilitate concurrent field monitoring during MR experiments.
• This approach is compatible with standard clinical scanner RF capabilities.
• Opens new avenues for advanced MR imaging techniques.