[Examination of gallstones on their surface and in fractured cross sections by incident light microscopy and scanning electron microscopy (author's transl)].

Operatively removed gallstones were examined on their surfaces and in fractured cross sections by incident light microscopy and scanning electron microscopy. In addition, micro-bore samples and X-ray crystallography were done. Five gallstone types consisting of three basic structural layers are differentiable by incident light microscopy. The three layers consist of a central nucleus which is always present, a radially structured middle layer, and a fine crystalline outer shell, the presence or absence of the latter two layers differentiating the stone types. Two crystal structures could be differentiated by electron microscopy; a flat and a globular type. The nucleus is always of the globular crystalline type, while the outer layers are flat crystalline. From this we were lead to believe that the conditions in vivo, under which the different layers of a gallstone are built, change. The micro-bore samples lead us to believe that calcium is only secondarily layed down in the gallstone framework. White crystalline deposits, which were formed several seconds after fracture, were discovered on the fractured gallstone cross sections.