Efficacy of using red dichromatic imaging throughout endoscopic submucosal dissection procedure

Management of bleeding during endoscopic submucosal dissection (ESD) is critical. Red Dichromatic Imaging (RDI), a novel image-enhanced endoscopy technology, has been reported to improve the visibility of deep vessels and bleeding source compared to white light imaging (WLI). We hypothesized that using RDI during the entire cutting process (full time RDI ESD: FTR-ESD), higher R0 resection rate, shorter procedure time and fewer complications could be achieved. Therefore, the aims of the present study were to investigate the efficacy and safety of FTR-ESD.

This retrospective observational study included a total of 82 consecutive patients who underwent ESD by a single expert endoscopist for 40 esophageal, 17 gastric and 25 colorectal cancers at our institution from January 2018 to March 2021. The clinicopathological data were collected from patients' medical records and the treatment outcomes were analyzed according to the treatment phase (early; 57 WLI-ESD and late; 25 FTR-ESD).

The median of the greatest diameter of resected specimen was 40.0 mm. The median procedure time was relatively shorter in the FTR-ESD group (35 min) than in the WLI-ESD group (40 min), but the difference was not statistically significant (p = 0.34). The median dissection speed in the FTR-ESD group (27.23 mm²/min) was significantly faster than that in the WLI-ESD group (20.94 mm²/min) (p = 0.025). The dissection speed was not different among different organs. A multivariate analysis revealed that tumor size (more than 30 mm) and FTR-ESD were significant independent factors contributing to faster dissection speed (p < 0.05). There were no significant differences in the rates of en bloc resection, HM0, VM0 or occurrence of adverse events between WLI-ESD and FTR-ESD.

FTR-ESD significantly increases the dissection speed compared to WLI-ESD. FTR-ESD can be performed safely and therapeutic outcomes in FTR-ESD are comparable with WLI-ESD. A further multicenter prospective study is warranted to confirm our results.