Preoperative Colonoscopic Tattooing Using a Direct Injection Method with Indocyanine Green for Localization of Colorectal Tumors: An Efficacy and Safety Comparison Study

PURPOSE: Endoscopic tattooing is used to mark colorectal lesions for subsequent surgery. As a tattooing agent, India ink has been widely used but is not currently available in Korea. Indocyanine green (ICG) can be applied as an alternative agent. However, studies on colonoscopic tattooing by the direct injection of indocyanine green are lacking. This study aimed to compare the efficacy and safety between an ICG direct injection method and an India ink saline test injection method. METHODS: A total of 227 patients who underwent preoperative endoscopic tattooing for colorectal neoplasm (149 patients in the ICG direct injection group and 78 patients in the India ink saline test injection group) were included in the study. The efficacy of the two methods was compared by visualization and safety was compared by evaluating the perioperative tattooing complications. RESULTS: The visualization of lesions in the ICG group was not different from that of the India ink group (p=0.42, 96.0% vs 98.7%, respectively). Only one patient in the ICG group had abdominal pain related to tattooing, but no complications developed in the India ink group. CONCLUSION: Considering the good visualization and low complication rate, the direct injection of ICG can be used as an alternative tattooing method.