[Localization and distribution of calcium salt in gallstones. A scanning electron microscopic study with energy-dispersive elemental analysis (author's transl)].

The surface of 68 fractured gallstones (28 patients) was investigated by SEM with energy-dispersive elemental analysis to show the topography of calcium salts. The localization of calcium salt is important with regard to chemolitholysis of calcium-containing cholesterol gallstones. The stones of 15 patients showed a concentration of calcium in the nucleus: in 4 the calcium salt was concentrated in the shell of the stone. In two more cases it was determined that calcium was present in both nucleus and shell. In seven it was impossible to place the stones in one of the above classes. Calcium salt in the shell seems to impede lysis by chenodeoxycholic acid; in these stones there is a small amount of insoluble calcium salt in the nucleus which remains after possible lysis of a cholesterol shell. The most appropriate stones for therapy with chenodeoxycholic acid are apparently those which harbor calcium salts with diffuse localization, so that no distinct nucleus no shell can be seen.