Vs120 fl

The basic specifications of fluorescence imaging systems has been reported previously.24 Briefly, macroscopic images were captured using a fluorescence reflectance imaging system (OV100; Olympus, Tokyo, Japan) equipped with a 150 W xenon light source and a color digital CCD camera (DP71; Olympus). Excitation and emission filters for ICG fluorescence imaging were 730 ± 22.5‐nm band‐pass and 770‐nm long‐pass filter, respectively. High‐power view was observed using a multi‐wavelength laser scanning microscope (IV100; Olympus) equipped with a 748‐nm diode laser with 17 mW power output and a photomultiplier tube. The emission filter to detect ICG fluorescence was a 779‐nm long‐pass filter. Tissue sections were scanned using a fluorescence virtual microscopy system (VS120‐FL; Olympus) equipped with a 200 W mercury light source (X‐Cite exacte; Excelitas Technologies, Waltham, MA, USA) and a monochrome digital CCD camera (ORCA‐R2; Hamamatsu Photonics, Hamamatsu, Japan). Excitation and emission filters for ICG fluorescence were 708 ± 37.5‐nm band‐pass and 809 ± 40.5‐nm band‐pass filter, respectively. Fluorescence images are shown in grayscale or pseudo‐colors.