Triple-clad W-type fiber mitigates multipath artifacts in multimodal optical coherence tomography

Area of Science:

• Biomedical Optics
• Fiber Optics Engineering
• Medical Imaging

Background:

• Multimodal endoscopic imaging combines optical coherence tomography (OCT) with other modalities for enhanced diagnostics.
• Double-clad fiber (DCF) offers potential for multimodal endoscopic systems but introduces multipath artifacts in OCT.
• Existing single-mode fiber OCT systems lack the multimodal capabilities of DCF.

Purpose of the Study:

• To investigate the mechanisms of multipath artifacts in DCF-based OCT.
• To propose and evaluate a W-type fiber as a solution for artifact-free multimodal endoscopic OCT.
• To demonstrate the efficacy of W-type fiber in an endoscopic system for high-quality imaging.

Main Methods:

• Modal analysis of W-type fiber using commercial software and experimental measurements.
• Comparison of modal content between W-type fiber, DCF, and single-mode fiber.
• Implementation of a W-type fiber rotary catheter in a DCF-based endoscopic OCT and autofluorescence imaging (AFI) system.

Main Results:

• Multipath artifacts in DCF-OCT were identified and linked to modal contents.
• W-type fiber simulations showed superior modal control compared to DCF.
• The W-type fiber rotary catheter successfully enabled artifact-free OCT and AFI of a human fingertip.

Conclusions:

• W-type fiber is a viable solution for achieving high-quality, artifact-free OCT in multimodal endoscopic systems.
• This advancement facilitates improved diagnostic capabilities in minimally invasive procedures.
• The proposed W-type fiber design overcomes limitations of DCF for advanced endoscopic imaging.