Published online Jul 16, 2021. doi: 10.4253/wjge.v13.i7.233
Peer-review started: December 18, 2020
First decision: December 31, 2020
Revised: January 14, 2021
Accepted: June 25, 2021
Article in press: June 25, 2021
Published online: July 16, 2021
Red dichromatic imaging (RDI) is a novel image-enhanced endoscopy expected to improve the visibility of the bleeding point. However, it has not been thoroughly investigated.
A 91-year-old man developed a sudden massive hematochezia and underwent emergent colonoscopy. An ulcer with pulsatile bleeding was found on the lower rectum. Due to massive bleeding, the exact location of the bleeding point was not easy to detect with white light imaging (WLI). Upon switching to RDI, the bleeding point appeared in deeper yellow compared to the surrounding blood. Thus, RDI enabled us for easier recognition of the bleeding point, and hemostasis was achieved successfully. Furthermore, we reviewed endoscopic images and evaluated the color difference between the bleeding point and surrounding blood for WLI and RDI. In our case, the color difference of RDI was greater than that of WLI (9. 75 vs 6. 61), and RDI showed a better distinguished bleeding point from the surrounding blood.
RDI may improve visualization of the bleeding point by providing better contrast in color difference relative to surrounding blood.
Core Tip: Red dichromatic imaging (RDI) is a novel image-enhanced endoscopy presumed to improve the visibility of the bleeding point but has not yet been fully explored. We present a case in which RDI effectively identified the bleeding point in an acute hemorrhagic rectal ulcer lesion with an analysis of color difference compared to white light imaging. RDI may enable easier recognition of the bleeding point by enhancing the color contrast of the bleeding point relative to the surrounding blood.