Caroli disease: high-frequency US and pathologic findings.

Three infants with nonobstructive bile duct dilatation (Caroli disease) are described. The bile duct pathology was associated with autosomal recessive polycystic kidney disease in two patients and with severe destruction of the renal parenchyma of unknown origin in the other. Sonograms of the liver showed, besides bile duct dilatations, intraluminal bulbar protrusions, bridge formation across dilated lumina, and portal radicles partially or completely surrounded by dilated bile ducts. Liver biopsy was performed in two patients, and in one patient, the biopsy sample confirmed the findings noted on sonograms. These findings support the hypothesis that the normal embryogenesis of intrahepatic bile ducts is arrested in the pathogenesis of this disease.