Fully Distributed Shape Sensing of a Flexible Surgical Needle Using Optical Frequency Domain Reflectometry for...

Area of Science:

• Medical Devices
• Biomedical Engineering
• Sensing Technology

Background:

• Accurate needle placement is critical for minimally invasive procedures like biopsies and brachytherapy.
• Current tracking methods face limitations in reliability, resolution, and image contrast, leading to frequent adjustments and reinsertions.

Purpose of the Study:

• To develop and validate an optimized needle shape-sensing method for precise needle placement.
• To overcome the limitations of existing tracking technologies in interventional procedures.

Main Methods:

• Utilized a fully distributed grating-based sensor with optical frequency domain reflectometry (OFDR).
• Employed trigonometric and geometric modeling for fiber shape analysis, independent of tissue properties.
• Incorporated a reproducible calibration process and a novel tip curvature compensation method.

Main Results:

• Achieved submillimeter accuracy (average RMSE from 0.58 ± 0.21 mm to 0.66 ± 0.20 mm).
• Validated the method in artificial isotropic and inhomogeneous animal tissues using 3D stereo vision and CBCT.
• Demonstrated a reliable and accurate needle shape-sensing approach.

Conclusions:

• The optimized needle shape-sensing method significantly enhances accuracy in minimally invasive procedures.
• This technology offers a promising solution for improving needle placement precision and reducing procedural complications.
• The developed method is suitable for real-time guidance in image-guided interventions.