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Significance: Color differences between healthy and diseased tissue in the gastrointestinal (GI) tract are detected visually by clinicians during white light endoscopy; however, the earliest signs of cancer are often just a slightly different shade of pink compared to healthy tissue making it hard to detect. Improving contrast in endoscopy is important for early detection of disease in the GI tract during routine screening and surveillance. Aim: We aim to target alternative colors for imaging to improve contrast using custom multispectral filter arrays (MSFAs) that could be deployed in an endoscopic "chip-on-tip" configuration. Approach: Using an open-source toolbox, Opti-MSFA, we examined the optimal design of MSFAs for early cancer detection in the GI tract. The toolbox was first extended to use additional classification models (k-nearest neighbor, support vector machine, and spectral angle mapper). Using input spectral data from published clinical trials examining the esophagus and colon, we optimized the design of MSFAs with three to nine different bands. Results: We examined the variation of the spectral and spatial classification accuracies as a function of the number of bands. The MSFA configurations tested showed good classification accuracies when compared to the full hyperspectral data available from the clinical spectra used in these studies. Conclusion: The ability to retain good classification accuracies with a reduced number of spectral bands could enable the future deployment of multispectral imaging in an endoscopic chip-on-tip configuration using simplified MSFA hardware. Further studies using an expanded clinical dataset are needed to confirm these findings. [ABSTRACT FROM AUTHOR]

Gastrointestinal cancers continue to account for a disproportionately large percentage of annual cancer deaths in the United States. Advancements in miniature imaging technology combined with a need for precise and thorough tumor detection in gastrointestinal cancer screenings fuel the demand for new, small-scale, and low-cost methods of localization and margin identification with improved accuracy. Here, we report the development of a miniaturized, chip-on-tip, multispectral, fluorescence imaging probe designed for compatibility with a gastroscope working channel with the aim of detecting cancerous lesions in point-of-care endoscopy of the gastrointestinal lumen. Preclinical testing has confirmed fluorescence sensitivity and supports that this miniature probe can locate structures of interest via detection of fluorescence emission from exogenous contrast agents. This work demonstrates the design and preliminary performance evaluation of a miniaturized, single-use, chip-on-tip fluorescence imaging system, capable of detecting multiplexed fluorophores, and devised for deployment via the accessory channel of a standard gastroscope. [ABSTRACT FROM AUTHOR]

Multispectral fluorescence imaging (MSFI) is a technique that measures endogenous and exogenous tissue fluorescence to reveal crucial insights into underlying biological mechanisms. Developing well-characterized high-performance fluorescence imaging equipment is crucial to any clinical or research application. Considering the diverse range of clinical scenarios and ongoing research areas in biomedicine leveraging MSFI instrumentation, there is an evident and pressing need for comprehensive resources that detail the development of such tools. This study provides a template for developing an MSFI instrument by highlighting the development and verification of our instrumentation. We present the design roadmap alongside the development of a large-area MSFI instrument to measure tissue fluorescence and diffuse reflectance properties. We divide our design approach into four subsections, highlighting the important physical milestones: illumination, imaging, detection, and computation. Each subsection includes design considerations, the methods used to validate the performance, and finally, the results and discussion of the validation process. We present the validation of the instrument across the illumination, imaging, detection, and computation subsystems. Two fluorophores are used to validate the instrument through serial dilution to establish a detection threshold and spectral capabilities limit. A mouse model expressing multi-colored fluorescent proteins is used to verify the multispectral performance. Our study lays out the groundwork for researchers to design and validate their own MSFI instrument. We present this alongside our instrument design to study fluorescence and diffuse reflectance properties of large-area tissues, such as murine or resected surgical specimens. Findings from the application of MSFI instrumentation can be translated to motivate and guide the design of fluorescence-based medical tools for the clinic or research environment. [ABSTRACT FROM AUTHOR]