Visualization of the lateral edge of the liver in ascites.

Medial displacement of the liver was observed in 35 cases of ascites using plain radiographs, total-body opacification, tomography, radionuclide imaging, peritoneography, and/or ultrasonography. In 16 cases the displaces liver was seen on plain radiographs. Separation of the liver and kidney was seen on ultrasonograms in every case; it was increased by addition of increments of fluid in patients undergoing peritoneal dialysis. Since the liver is surrounded by fluid, an interface between it and the extraperitoneal fat cannot account for the displacement seen on plain radiographs: rather, this is the result of a difference in density between liver and fluid.