[Reference values in abdominal ultrasound - biliopancreatic system and spleen]

Reference values for B-mode abdominal ultrasound are controversially discussed due to the limited data in the literature. A systematic survey of the data published so far is presented for the biliopancreatic system and the spleen.

A literature review of reference values in the abdomen from 1970 to 2010 in healthy subjects 18 years of age and older was carried out. According to the determination of reference intervals for laboratory values, reference values are generally determined using 95 %-reference intervals and their associated 90 %-confidence intervals. The gallbladder, gallbladder wall, bile ducts, pancreas and the spleen were evaluated.

70 studies were analysed. The comparability of the data is limited, because different collectives were studied and diverse measuring techniques were used. In particular, gallbladder volume measurements reported in the literature differ substantially. Data for the size of the gallbladder are insufficient. Deducible reference values for the common hepatic duct or, respectively, the common bile duct lie between 5 and 9 mm in dependency on the measuring position and the collective analysed. The published measurement values for the size of the pancreas also vary considerably. In most of the publications the upper limit of normal for the length of the spleen amounts to around 12 cm, in young, athletic men up to 15 cm.

Normal values are helpful in delimiting numerous pathological changes in the respective organs.