Amylase level in extrahepatic bile duct in adult patients with choledochal cyst plus anomalous pancreatico-biliary ductal union

Figure 1 Endoscopic retrograde cholangiopancreatogram of choledochal cyst and microscopic change of extrahepatic bile duct. A: Todani type I and APBDU; B: Todani type IVa and APBDU; C: infiltration of small number of lymphocytes (inflammatory grade I); D: extensive infiltration of lymphocytes with surface erosion (inflammatory grade III); E: papillary epithelial growth, less than one-third (hyperplasia grade I); F: papillary epithelial growth, more than two-thirds (hyperplasia grade III).