Kinetics of indocyanine green: Optimizing tumor to normal tissue fluorescence in image‐guided oral cancer surgery applications

Abstract Background The study aimed to define indocyanine green (ICG) kinetics to determine the optimal ICG dose and surgical time for near‐infrared fluorescence‐guided oral cancer surgery. Methods Spectrometer and grayscale digital imaging were used to quantify the ICG kinetics in 12 patients with oral cancer. The fluorescence intensity and signal‐to‐background ratio (SBR) of tumor and normal tissue were tested at 1, 6, and 24 hours after ICG injection. Results The greatest contrast in the fluorescence intensity between tumor and normal tissue was observed at 6 hours ( P < .01), and of three dose groups (0.5, 0.75, and 1.0 mg/kg), 0.75 mg/kg showed the highest SBR (2.06 ± 0.23) after ICG injection. Conclusions Fluorescence quantification based on spectrometry and grayscale imaging could be effective in determining the optimal ICG dose and surgical time after ICG injection in this cohort of patients with oral cancer.