[Principal methods for studying the composition and structure of urinary calculi]

Abstract

Since stones are the only objective elements of lithiasis, the cause of this disease can only be determined by an accurate analysis of the morphology and composition of the stones. To identify the crystal phases and the distribution of constituents between superficial and central structures such efficient techniques as scanning electron microscopy, X-ray diffraction or infrared spectroscopy are required. At least two complementary techniques must be combined to obtain enough information on the morphology as well as on the molecular and crystalline composition of the stones. The importance of morphological typing for the aetiological evaluation of the disease is demonstrated by examples which clearly show that each stone must first be examined optically. The different techniques used for the study of stones are reviewed and their relative efficiency and adaptability to routine analysis is discussed.