Multispectral Imaging and Label-Free Capsule Endoscopy for Noninvasive Detection of Digestive Tract Vessels

Area of Science:

• Gastroenterology and Biomedical Engineering
• Optical Imaging and Spectroscopy
• Minimally Invasive Medical Devices

Background:

• Current diagnostic methods for digestive tract (DT) diseases, including wired endoscopy and capsule endoscopy (CE), face limitations such as invasiveness, risks of exogenous fluorescence, poor white-light imaging (WLI) contrast, and restricted information acquisition.
• There is a critical need for noninvasive imaging techniques that can accurately visualize DT vasculature to improve diagnostic capabilities and patient outcomes.

Purpose of the Study:

• To develop and evaluate a novel label-free multispectral imaging capsule endoscopy (MICE) system for noninvasive detection and characterization of DT vasculature.
• To demonstrate the capability of MICE to provide depth-specific and multilayered vascular information, surpassing the limitations of conventional imaging modes.

Main Methods:

• Development of a MICE system capable of white-light examination and depth-specific imaging at 420 nm, 540 nm, and 590 nm.
• Synergistic multispectral operation enabling blue-light imaging (BLI), narrow-band imaging (NBI), and dual-red imaging (DRI) for comprehensive vascular assessment.
• Integration of wireless power transfer (WPT) and magnetic control (MC) for stable operation and precise locomotion of the MICE platform.
• Proof-of-concept evaluation using porcine DT mucosa to assess imaging performance and vessel-to-background contrast.

Main Results:

• MICE successfully captured depth-varying vascular information on porcine DT mucosa at different wavelengths (420, 540, 590 nm).
• Vessel-to-background contrast significantly improved over WLI, with contrast gains of 2.90, 1.94, and 1.21 at respective wavelengths.
• Fusion visualization of multilayered vascular data was achieved through BLI, NBI, and DRI, providing morphologically rich information.
• The integrated WPT and MC system ensured stable power supply and precise maneuverability of the MICE device.

Conclusions:

• This study presents the first label-free MICE system for noninvasive detection of DT vasculature, offering significant advantages over existing methods.
• The MICE system enhances visualization and depth differentiation of mucosal vascular morphology, leading to improved diagnostic accuracy for DT diseases.
• The developed technology holds substantial clinical implications for noninvasive diagnosis and management of various digestive tract conditions.