Congenital dilatation of the biliary tract; new classification and study with particular reference to anomalous arrangement of the pancreaticobiliary ducts.

Yotsuyanagi's theory is often quoted in the discussion of the etiology of congenital dilatation of the biliary duct (CDBD), but there has been no established etiology as yet. With particular reference to the relationship between anomalous arrangement of the pancreaticobiliary ducts and CDBD, Babbit collected 19 cases of CDBD. The authors also observed the anomalous arrangement in 10 of 24 cases of CDBD (42 percent). Analysis of 570 CDBD cases collected in Japan disclosed that the anomalous arrangement was present in 183 of them (33 percent), dilation of the intraheptic bile ducts in 236 (42 percent), and narrowing and malformation of the bile duct in the hepatic hilum in 58 (10 percent). The authors have proposed a new classification, including these morphologic anomalies of the whole pancreaticobiliary ductal system. This classification provides useful indices in selecting the surgical procedures. The effect of the anomalous arrangement was pathophysiologically studied on dogs. The static internal pressure of the dog pancreatic duct was 14.6 + or - 5.5 cm H2O, and that of the dog bile duct, 8.9 + or - 3.4 cm H2O. Puppies were then operated on by shunting the pancreaticobiliary ducts. As the result, the biliary tract was devastated by pancreatic juice, giving rise to similar pathologic changes to those clinically observed.