A Framework to Optimize Channel and Active Area Usage in Multicore Fibers for Needle Shape Sensing

Area of Science:

• Biomedical Engineering
• Optical Fiber Sensing
• Medical Device Design

Background:

• Interstitial brachytherapy requires precise needle guidance.
• Multicore fibers (MCFs) with fiber Bragg gratings (FBGs) offer potential for shape sensing.
• Optimizing MCF hardware parameters is crucial for accurate performance.

Purpose of the Study:

• To develop a process for evaluating hardware design parameters' impact on MCF stylet performance for shape sensing.
• To identify optimal configurations of active areas (AAs) and channel arrangements for improved reconstruction accuracy.
• To establish a framework for post-fabrication optimization of MCFs.

Main Methods:

• Evaluated hardware performance using two constant-curvature jig datasets.
• Assessed the influence of AA number and spacing on reconstruction accuracy.
• Analyzed seven-core and four-core fiber channel configurations.
• Conducted a joint analysis for globally optimal stylet configuration.

Main Results:

• Identified AA configurations yielding the lowest reconstruction errors.
• Determined optimal channel configurations for seven-core and four-core fibers.
• Achieved a statistically significant 34% reduction in tip error with the optimized stylet.
• Demonstrated significant improvement over the full-sensor configuration.

Conclusions:

• The study provides practical guidance for selecting MCFs for shape sensing applications.
• A new framework for post-fabrication optimization of multicore fibers has been established.
• Optimized MCF stylets enhance accuracy in medical device guidance systems.