Optical Fiber -Based Needle Shape Sensing: Three-channel Single Core vs. Multicore Approaches.

Area of Science:

• Biomedical Engineering
• Sensing Technologies
• Medical Devices

Background:

• Percutaneous interventions often require curved needle trajectories.
• Accurate needle shape sensing and tip localization are vital for procedural guidance.
• Fiber Bragg Grating (FBG) sensors are explored for medical applications, but fiber type selection varies.

Purpose of the Study:

• To compare the performance of two distinct Fiber Bragg Grating (FBG) sensor types for needle insertion shape reconstruction.
• To evaluate the suitability of single-core versus multi-core fiber for real-time needle guidance.

Main Methods:

• Constructed a three-channel single-core fiber needle and a seven-channel multi-core fiber (MCF) needle.
• Integrated both needle types with FBG sensors for shape sensing.
• Conducted experiments using constant curvature jigs to assess shape reconstruction accuracy.

Main Results:

• The single-core fiber needle achieved an overall needle tip error of 1.23 mm.
• The multi-core fiber (MCF) needle resulted in an overall needle tip error of 2.08 mm.
• Identified pros and cons for each fiber construction in shape sensing applications.

Conclusions:

• Single-core FBG sensors offer higher accuracy for needle shape sensing compared to MCF sensors in this application.
• The choice of fiber type significantly impacts the precision of needle tip localization for percutaneous interventions.