Targeted vertical cross-sectional imaging with handheld near-infrared dual axes confocal fluorescence endomicroscope

Area of Science:

• Medical Imaging
• Gastroenterology
• Biomedical Engineering

Background:

• Confocal endomicroscopy enables in vivo imaging of gastrointestinal tissues.
• Current systems may lack the resolution or orientation needed for detailed pathological assessment.
• Targeted molecular imaging requires high-resolution visualization of specific biomarkers.

Purpose of the Study:

• To demonstrate a handheld dual-axis confocal endomicroscope capable of generating vertical cross-sectional (XZ-plane) images.
• To visualize the specific binding of a near-infrared (NIR) fluorescently labeled peptide to pre-malignant colonic mucosa.
• To assess the histology-like imaging performance of this miniature instrument.

Main Methods:

• A handheld dual-axis confocal endomicroscope with a 10 mm outer diameter scan head was utilized.
• The system integrates a 1D microelectromechanical systems (MEMS) X-axis scanner and a PZT Z-axis actuator.
• Raster scanning produced vertical cross-sectional images with NIR fluorescence, visualizing Cy5.5-labeled peptide binding.

Main Results:

• Vertical cross-sectional (XZ-plane) images of NIR fluorescence were successfully acquired.
• Specific binding of a Cy5.5-labeled peptide to pre-malignant colonic mucosa was visualized.
• The endomicroscope achieved transverse and axial resolutions of 4 μm and 5 μm, respectively, over an 800 μm x 400 μm field-of-view.

Conclusions:

• The developed handheld confocal endomicroscope provides histology-like vertical cross-sectional imaging.
• This technology enables visualization of molecular targets in pre-malignant colonic tissue.
• The miniature instrument shows promise for advanced gastrointestinal diagnostics.