Liver transection using indocyanine green fluorescence imaging and hepatic vein clamping

Background: Three-dimensional (3D) imaging has facilitated liver resection with excision of hepatic veins by estimating the liver volume of portal and hepatic venous territories. However, 3D imaging cannot be used for real-time navigation to determine the liver transection line. This study assessed the value of indocyanine green (ICG) fluorescence imaging with hepatic vein clamping for navigation during liver transection. Methods: Consecutive patients who underwent liver resection with excision of major hepatic veins between 2012 and 2013 were evaluated using ICG fluorescence imaging after clamping veins and injecting ICG. Regional fluorescence intensity (FI) values of non-veno-occlusive regions (FI_Non), veno-occlusive regions (FI_VO) and ischaemic regions (FI_IS) were calculated using luminance analysing software. Results: Of the 21 patients, ten, four and seven underwent limited resection, monosegmentectomy/sectionectomy and hemihepatectomy respectively, with excision of major hepatic veins. Median veno-occlusive liver volume was 80 (range 30–458) ml. Fluorescence imaging visualized veno-occlusive regions as territories with lower FI compared with non-veno-occlusive regions, and ischaemic regions as territories with no fluorescence after intravenous ICG injection. Median FI_IS/FI_Non was lower than median FI_VO/FI_Non (0·22 versus 0·59; P = 0·002). There were no deaths in hospital or within 30 days, and only one major complication. Conclusion: ICG fluorescence imaging with hepatic vein clamping visualized non-veno-occlusive, veno-occlusive and ischaemic regions. This technique may guide liver transection by intraoperative navigation, enhancing the safety and accuracy of liver resection.