Polarized light microscopic examination of human bile in the diagnosis of microlithiasis of the gallbladder.

Of the 20 cases with biliary colics who had normal OCG and ultrasound, 11 (55%) showed microlithiasis in the form of cholesterol monohydrate crystals and/or calcium bilirubinate granules on polarized light microscopy of the duodenal bile. Microlithiasis was noted in gallbladder bile of all (100%) the cases with proven gallstones but in none of the duodenal bile samples from healthy subjects. This study suggests that polarized microscopy may be a useful method to detect microlithiasis in patients with repeated biliary colics who have normal OCG and ultrasound examination.