ULTRASOUND APPEARANCES OF INTRA-HEPATIC AND EXTRAHEPATIC BILIARY ASCARIASIS

Background: To determine the range of ultrasonographic (US) appearance s of Ascaris lumbricoides roundworms in the biliary system, their dist ribution in the intra- and extrahepatic parts of the system, and assoc iated features. Methods: All cases of biliary ascariasis during a 10-y ear period were reviewed. There were 42 cases in which diagnosis was b ased on established US criteria, and 2 cases diagnosed surgically in w hich US had been negative. These 44 cases occurred in 36 patients. Res ults: In the US-diagnosed cases, worms were present in intrahepatic du cts in 32 cases, in the main duct in 37, and in the gallbladder in eig ht. In six cases, the liver was lifted off the main portal vein by a b undle of worms obliterating the lumen of the main bile duct. Worms pac king and dilating intrahepatic ducts produced pseudotumorous appearanc es in the liver in four cases and bundlelike appearances in three. Wor ms were also seen in the pancreatic duct in two cases. Stones in intra hepatic ducts were present in 12 patients. Conclusion: Biliary ascaria sis should be searched for inside and outside the liver, The appearanc es of bundles and boluses are different from those of single worms. In tra-and extrahepatic biliary stones may be present.