Changes of hepatic volume after successful Kasai operation.

The number of long term survivors who have undergone Kasai operation for biliary atresia is increasing, but some have a hepatic dysfunction likely to require liver transplantation in the near future. Hepatic volume possibly reflects whole liver function, and our objective was to assess the changes of hepatic volume after Kasai operation. Ten patients were studied. Ages ranged from 3 to 27 years. They underwent Kasai operation at ages ranging from 50 to 80 days. Liver areas (cm2) on CT images were measured with an image processing and analysis program (NIH Image 1.57). Hepatic volume (cm3) was calculated by summing up the areas of each image and multiplying by slice thickness (cm). After Kasai operation, the size of the liver increased to 1.7-1.9 times the standard volume, and then reduced to normal size around 5 years of age. In the teens, hepatic volume decreased below the standard volume. Segmental hypertrophy accompanying atrophy of other hepatic segments was observed in 9 out of 10 patients; right lobe hypertrophy: 6, medial segment: 2, and lateral segment: 1. Therefore, progressive hepatic atrophy begins in the teens, but is compensated for by segmental hypertrophy.