Shaffer H A, Harrison R B
Gastrointest Radiol. 1978 Apr 15;3(1):33-7. doi: 10.1007/BF01887032.
The stratification (layering) phenomenon in the gallbladder is a source of errors in interpretation of intravenous cholangiography. It may mimic stones that do not exist or conceal stones that do. To avoid false-positive or false-negative interpretations, it is suggested that delayed films be taken at 4 hours in cases which demonstrate a layering phenomenon. By this time, a normal gallbladder will be homogeneously opacified and a diseased one will reveal its stones. Horizontal beam roentgenograms are mandatory for complete evaluation.
胆囊中的分层现象是静脉胆管造影解读错误的一个来源。它可能会模拟不存在的结石或掩盖存在的结石。为避免假阳性或假阴性解读，建议在出现分层现象的病例中于4小时拍摄延迟片。此时，正常胆囊会均匀显影，而病变的胆囊会显示出结石。为进行全面评估，必须拍摄水平束X线片。
