A Fabry-Perot Interferometry Based MRI-Compatible Miniature Uniaxial Force Sensor for Percutaneous Needle Placement

Area of Science:

• Medical Robotics
• Biomedical Engineering
• Surgical Navigation

Background:

• Robot-assisted surgery leverages Magnetic Resonance Imaging (MRI) for enhanced visualization.
• Maintaining tactile force feedback is essential for MRI-guided needle-based interventions.
• Current systems often lack precise force sensing capabilities within the MRI environment.

Purpose of the Study:

• To develop and integrate an MRI-compatible fiber optic sensor system for tactile force feedback.
• To enable precise force measurement during robot-assisted prostate cancer biopsy and brachytherapy.
• To improve the safety and efficacy of MRI-guided robotic surgical procedures.

Main Methods:

• A Fabry-Perot interference (FPI) based fiber optic sensor was designed and miniaturized.
• The sensor was integrated into a piezoelectric robot for measuring needle insertion force.
• Finite element analysis was used to optimize the sensor's force-deformation characteristics.
• The system was calibrated within a 3T MRI scanner.

Main Results:

• The developed opto-electronic sensing system was successfully integrated into an MRI-compatible robot.
• Calibration demonstrated a root mean square error of 0.318 Newton within the 0-10 Newton range.
• The system proved sufficient for robot control and teleoperation in MRI-guided procedures.

Conclusions:

• The compact, low-cost FPI sensing system effectively provides tactile force feedback in MRI environments.
• This technology enhances the capabilities of robot-assisted surgery for prostate cancer interventions.
• The system offers a viable solution for improving control and safety in real-time MRI-guided procedures.