Approaches to creating and controlling motion in MRI

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Materials Science

Background:

• Magnetic Resonance Imaging (MRI) offers high-resolution 3D imaging crucial for interventional guidance and monitoring.
• Developing MRI-compatible devices faces challenges like magnetic field interference, image quality preservation, and space constraints.
• Piezoelectric actuators are favored for MRI-guided interventions due to precision and non-magnetic operation, but can degrade image quality.

Purpose of the Study:

• To develop and validate a novel piezoelectric actuator driver and control system for MRI-guided interventions.
• To address the issue of image quality degradation caused by piezoelectric actuators during MRI procedures.
• To create a versatile system capable of controlling various actuator types with minimal impact on MRI image quality.

Main Methods:

• Designed a new piezoelectric actuator driver and control system.
• Tested the system's performance with both harmonic and non-harmonic piezoelectric actuators.
• Evaluated image quality by measuring Signal-to-Noise Ratio (SNR) loss under closed-loop control.

Main Results:

• The developed system successfully drove both harmonic and non-harmonic piezoelectric actuators.
• Demonstrated minimal image degradation, with less than 5% SNR loss under closed-loop control.
• The system allows a single controller to manage diverse actuators and feedback sensors without hardware modification.

Conclusions:

• The new driver and control system effectively mitigates image quality issues associated with piezoelectric actuators in MRI.
• This technology enhances the feasibility and performance of MRI-guided interventions.
• The universal controller design offers flexibility and reduces complexity in developing MRI-compatible interventional devices.