ARE MORPHOLOGY AND COMPOSITION OF GALLSTONES RELATED - AN X-RAY-DIFFRACTION STUDY

An x-ray diffractometric technique was used to study the crystalline c omposition of gallstones removed during surgery from 106 patients. Mon ohydrate cholesterol was found in the stones of 70 (66%) patients, eit her alone (33%) or in association with calcium salts (33%). The anhydr ous form of cholesterol was found in the stones of 28 (26%) patients, either alone (1O%) or in association with calcium salts (16%). These s alts (vaterite, aragonite, and calcite) were found in 50% of cases in varying amounts (from 12% to 15% of the stone weight). Eight stones co ntained no cholesterol: 4 showed an amorphous pattern and 4 were compo sed of calcium carbonate salts. In 7 of 8 patients with bile duct ston es concomitant with gallbladder stones, results of the diffractograms of the stones from the two different sites were comparable, even in 4 cases in which the stones were macroscopically different. Neither the macroscopic appearance nor the chemical structure of the stones appear ed to be influenced by the patient's sex.