Partial nephrectomy has recently been the standard operation for patients with small renal tumors, but it's challenging to accurately differentiate tumor from normal parenchyma. Tobis et al has performed ICG fluorescence imaging technique with 19 patients to detect renal tumors, and after ICG administration, 13 malignant tumors all appeared to be less-fluorescent and benign tumors behaved from equal-fluorescent to over-fluorescent compared with normal parenchyma, which was greatly beneficial to maximal nephron preservation . The authors believed the differences of the relative fluorescence were obvious enough to the naked eyes of different surgeons to make the agreeable subjective determinations of qualitative fluorescence, but they also admitted it would be more accurate and useful if fluorescence intensity can be objectively quantitative measured which was unachievable currently.