Fig. 1.

ICG application in laparoscopic colorectal surgery. Conventional dosage of ICG (total injected dose of 25 mg at 2.5 mg/ml, injected in doses of 2.5 ml) was injected into submucosa of the four quadrants surrounding the cancer (A). Tattooing with conventional protocol makes the gross localization possible using the naked eye (B); however, under NIR illumination, it is harder to distinguish the cancer from the surrounding tissues (C). ICG angiography was disturbed by the stained surrounding tissues following conventional tattooing (D). FLNM failed because of the influence of the stained mesentery following the use of a high dose of tattooing agent (E). Endoscopic tattooing with diluted ICG is suggested as the optimal protocol (total injected dose of 0.5 mg at 0.25 mg/ml, injected in doses of 1 ml at two separate sites) (F). The gross localization of the tumor was challenging (G); a definite separation between tumor and surroundings was seen using the NIR system (H). Successful ICG angiography was performed (I), and FLNM was well established under NIR illumination (J)