4 literatures demonstrated that, ICG intraoperative imaging was successfully detected liver metastases lesions, some of which were even missed or undetected by other modalities, with the appearance of the clear fluorescent rims around the tumors . The mechanism of ICG accumulation in the transition area between tumors and normal liver tissue was investigated, that "the pattern of rim fluorescence could be explained by the presence of immature hepatocytes in the liver tissue surrounding the tumor that have taken up ICG, but exhibit impaired biliary clearance" . Vahrmeijer et al. reported ICG was administered intravenously 24 or 48h prior to surgery , but Ishizuka and Morita demonstrated ICG can be retained around liver metastasis for 14days and 28days respectively. The mechanism of why ICG can be retained for such a long time is still not very clear. Though ICG imaging can detect overlooked lesions by other methods, there is also a relatively high false-positive proportion which can't be ignored .