Bimodal reflectance and fluorescence multispectral endoscopy based on spectrally resolving detector arrays

Area of Science:

• Medical Imaging
• Optical Engineering
• Biomedical Optics

Background:

• Clinical interest in early cancer detection drives demand for advanced imaging techniques.
• Combining white light endoscopy with near-infrared (NIR) fluorescence imaging offers improved diagnostic capabilities.
• Multimodal imaging endoscopes are needed to integrate these complementary techniques.

Purpose of the Study:

• To develop and characterize a bimodal spectral endoscope for simultaneous visible reflectance and NIR fluorescence imaging.
• To evaluate the system's performance in phantom and ex vivo models for biological component resolution.

Main Methods:

• Utilized two spectrally resolving detector arrays (SRDAs) for visible and NIR spectral regions.
• Designed a compact endoscope based on a "babyscope" model with a commercial imaging fiber bundle.
• Developed a spectral transmission model for component selection and spectral unmixing.

Main Results:

• The endoscope demonstrated encouraging technical performance, including spatial resolution and spectral fidelity.
• Successfully identified chemical components in an agarose phantom with high signal-to-background ratio (>3) after spectral unmixing.
• Preliminary ex vivo imaging in a porcine esophagus model showed capability to resolve multiple biological components.

Conclusions:

• The developed compact spectral endoscopy system can simultaneously resolve multiple biological components.
• This bimodal approach shows promise for enhanced early cancer detection and diagnostics.
• Further validation is needed for clinical translation.