Visualization of Cholecystic Venous Flow for Hepatic Resection in Gallbladder Carcinoma

It is well-known that some hepatic resection is required in T2 gallbladder carcinoma to ensure that microscopic metastases around the gallbladder bed are excised, but the appropriate extent of hepatic resection has not been established. Based on the results of clinical and pathological studies, hepatic wedge resection is currently performed 1-2 cm distant from the gallbladder bed; however, it is unclear whether this area is sufficient in each individual patient. We have developed the following technique using fluorescence angiography to determine the necessary extent of resection: indocyanine green is injected into the cholecystic artery, and cholecystic venous flow is then observed using a near-infrared camera system. This highly sensitive technique enables us to evaluate blood flow in real time. We classified fluorescence patterns into two types according to the site and timing of fluorescence. In type 1, cholecystic veins flow directly into the liver parenchyma adjacent to the gallbladder. In type 2, cholecystic veins flow into intraportal branches. We propose that the type 1 pathway is the main route of hepatic metastasis in early advanced gallbladder carcinoma. Sufficient hepatic resection around the gallbladder bed, whether anatomical or nonanatomical, is needed to prevent recurrence in the remnant liver. Using our newly developed fluorescence angiography technique, we now perform hepatic resection according to the cholecystic venous perfusion area.