The role of indocyanine green (ICG) in robotic liver surgery

Abstract

Introduction: The ability of ICG to provide a fluorescence appearance under infrared light enables its wide usage in surgical oncology. It is capable of identifying hepatic lesions intraoperatively and identifies anatomic sections in real time. The purpose of this study is to describe the technical aspects of its use and to evaluate the diagnostic value of ICG fluorescence in robotic liver surgery in a single-center. Methods: Patients who underwent robotic liver resection at Changi General Hospital for primary liver cancer and colorectal liver metastases (CLM) were included. All cases were completed robotically with daVinciXi. For identification of liver tumor, 5mg of ICG was given intravenously 1-3 days prior to surgery. For identification of anatomical segments, negative staining method was used by giving 5mg of intravenous ICG after clamping of the segmental inflow. Firefly fluorescence imaging was used for illumination. Results: A total of 9tumors were resected in 8patients. Of the 9 tumors, ICG was used for tumor identification in 4 and negative staining for anatomical resection in 6. All 4 tumors were successfully identified with ICG fluorescence. The anatomical resection performed were right posterior sectionectomy (n=4), right anterior sectionectomy (n=1), and right hepatectomy (n=1). Negative staining was clearly identified in 4 patients; however it was not demonstrated in two patients due to failure to tightly control the hepatic inflow. Conclusion: Robotic ICG fluorescence can provide clear identification of tumors on liver surface. Tight control of the inflow is crucial to obtain a successful real time negative staining for anatomical resection.