Optical microscopy versus scanning electron microscopy in urolithiasis

Abstract

Stone analysis is incompletely done in many clinical centers. Identification of the stone component is essential for deciding future prophylaxis. X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy (SEM) still remains a distant dream for routine hospital work. It is in this context that optical microscopy is suggested as an alternate procedure. The objective of this article was to assess the utility of an optical microscope which gives magnification of up to 40x and gives clear picture of the surface of the stones. In order to authenticate the morphological analysis of urinary stones, SEM and elemental distribution analysis were performed. A total of 250 urinary stones of different compositions were collected from stone clinic, photographed, observed under an optical microscope, and optical photographs were taken at different angles. Twenty-five representative samples among these were gold sputtered to make them conductive and were fed into the SEM machine. Photographs of the samples were taken at different angles at magnifications up to 4,000. Elemental distribution analysis (EDAX) was done to confirm the composition. The observations of the two studies were compared. The different appearances of the stones under optical illuminated microscopy were mostly standardized appearances, namely bosselations of pure whewellite, spiculations of weddellite, bright yellow colored appearance of uric acid, and dirty white amorphous appearance of phosphates. SEM and EDAX gave clearer pictures and gave added confirmation of the stone composition. From the references thus obtained, it was possible to confirm the composition by studying the optical microscopic pictures. Higher magnification capacity of the SEM and the EDAX patterns are useful to give reference support for performing optical microscopy work. After standardization, routine analysis can be performed with optical microscopy. The advantage of the optical microscope is that, it is easy to use and samples can be analyzed in natural color.

Application of Mineralogical Techniques in the Study of Human Lithiasis

“…In qualitative chemical analysis, the calculus is split approximately in half and a small quantity of powder is selectively taken from each of the different layers. The powder is mounted according to normal practice for microscope preparations [7]. A technique normally employed in soil micromorphology was used to make the thin sections [8]; this technique allowed thin cuts even from the smallest and most fragile kidney stones.…”

Structural and Optical Properties of Cetapin XR and Mathumagachooranam Added Struvite Crystals

“…This gives an idea that drugs used by the sugar patients may promote the stone formation as a side effect. Recently, there has been an increasing interest in growing crystals using gels as a model system for studying crystal deposition diseases in human beings [6][7][8][9][10]. Gel acts as an inert medium during the growth of many crystalline compounds and it acts as an ideal medium in the study of the crystallization of biomolecules in-vitro [11].…”