Fig. 3

Operative findings. a Preoperative scheme of the patient. Triangle: tumor. b Indocyanine green (ICG) fluorescence imaging. Right anterior section demonstrated evident fluorescence. Arrow head: serosal deformity from tumor. c Intraoperative ultrasonography. The tip of the bile duct tumor thrombus (BDTT) located at the hepatic side of the right hepatic duct. Arrow head: the bile duct of the right anterior branch. Arrow: the posterior branch, Asterisk: the tip of BDTT. d Intraoperative scheme after division of liver parenchyma. Triangle: tumor. e, f ICG fluorescence imaging before the division of the right hepatic duct. The light of emission from the bile duct and BDTT with clear contrast; the proximal side of the right hepatic duct exhibited stronger fluorescence than the proximal side. Arrow head: location of the BDTT tip in the right hepatic duct. Arrow: common hepatic duct. g After the removal of surgical specimen. Arrow head: stump of the right hepatic duct. Arrow: middle hepatic vein. h ICG fluorescence imaging of the bile duct after resection. Bile duct route from the left hepatic duct to the common hepatic duct is clearly visualized. Arrow head: stump of the right hepatic duct. Arrow: Bile duct route from the left hepatic duct to the common hepatic duct. Asterisk: stump of cystic duct