Usefulness of colonic tattooing using indocyanine green in patients with colorectal tumors

Figure 1 Flow chart of patients enrolled in this study. The 114 tattooed group subjects and the 228 non-tattooed group subjects were selected by propensity score matching. A total of 342 patients was enrolled.

Figure 2 Endoscopic tattooing using indocyanine green. Indocyanine green (ICG) tattooing was performed one day prior to colonoscopic surgery by the circumferential method. A: White light endoscopy image of early sigmoid colon cancer; B: Indigo carmine was used to determine the margin of the lesion; C: Between 1-2 mL of normal saline solution was injected into the submucosa to make an artificial pseudo polyp; D-F: Subsequently, the saline syringe was replaced by the ICG syringe, and 0.5-1 mL of dissolved ICG was injected. ICG: Indocyanine green.

Figure 3 Intraoperative photo. Tattooed area showing a green color (arrow). In the pathologic report, this lesion was 2.3 cm × 1.9 cm in size.

Figure 4 Pathologic specimen of the resected colon. An obvious green color is observed in the inner (A) and outer (B) sides of the colon.