The investigators have a series of surgical cases in which the investigators have been able to achieve excellent intraoperative biliary visualization with a greatly decreased (50-200 fold lower) dose of ICG than the previously published dose. Furthermore, this decreased dose was visible in about 15-20 minutes from the time of injection with low liver background fluorescence, a significant improvement that would make its utilization in the operating room more practical. The investigators hypothesize that a lower dose will: 1) allow adequate visualization of the extrahepatic biliary tree, including the cystic, common hepatic, and common bile ducts. Confirmation of hypotheses would mean that a lower dose of ICG can be administered on the same day of surgery in order to augment real-time intraoperative localization of the extrahepatic biliary tree, thereby providing a safe, feasible, and cost-effective strategy for the surgical treatment of liver disease.~The investigators intend to test our hypothesis with the following specific aims:~Aim 1: To compare the efficacy and utility of a low dose ICG (0.05 mg) protocol with a previously published dose (2.5 mg) in imaging the extrahepatic biliary tract.
Near-infrared fluorescence (NIRF) imaging after an intravenous injection of indocyanine green (ICG) allows for the intraoperative identification of liver anatomy. The investigators have new data that a much lower dose improves this visualization. Confirmation of this hypothesis would mean that ICG can be administered on the same day of surgery in order to augment real-time intraoperative visualization, thereby providing a safe, feasible, and cost-effective strategy for the surgical treatment of liver disease.