A microstructural study of gallbladder stones using scanning electron microscopy

The objective of this study was to describe the microstructure of different types of gallbladder stones to better understand the basis of gallbladder stone formation.

Gallbladder stones from 387 patients with cholecystolithiasis were first analyzed by Fourier transform Infrared spectroscopy to identify the type of the gallbladder stone, and they were then examined using scanning electron microscopy to define their microstructure.

Cholesterol stones were mainly composed of plate-like or lamellar cholesterol crystals stacked tightly in a radial, cord-like, or irregular staggered arrangement. A small number of bilirubinate particles were seen occasionally. Pigment stones were mainly composed of loosely arranged bilirubinate particles with different shapes (sphere-like, clumping-like, or amorphous). Calcium carbonate stones were composed of calcium carbonate crystals having many shapes (bulbiform, ellipsoid, fagot-shaped, fusiform, hawthorn-shaped, cuboid, button-shaped, lamellar, broken firewood-shaped, rod-shaped, acicular, or crushed sugar cane-shaped). Bulbiform shaped crystals were the most common. Phosphate stones were mainly composed of different sized echin-sphere-like or rough bulbiform crystals. Bilirubinate particles were always adherent. Calcium stearate stones usually had a network structure with adherent bilirubinate particles. Protein stones usually had a honeycomb or chrysanthemum petal-like structure. Cystine stones were composed of hexagonal cystine crystals, some of which had prominent edges. Mixed stones presented different shapes according to their mixed components.

Different types of gallbladder stones had characteristic shapes and elements. This study provides an objective basis for further research regarding gallbladder stone formation.