Fig. 2.

Optical guidance enabled by the hybrid tracer and blue dye. a Typical examples of procedures combining use of blue dye and the hybrid tracer ICG-^99mTc-nanocolloid in the head-and-neck region and groin. b Typical examples of procedures using only the hybrid tracer for optical guidance (head-and-neck and pelvic region). The second column demonstrates what is seen by eye, while the third column provides insight into the signal obtained via fluorescence imaging with a (laparoscopic) near-infrared dedicated fluorescence camera