COMPARATIVE ANALYSIS OF DATA FROM A DUAL-ENERGY COMPUTER TOMOGRAPH AND THE RESULTS OF A MINERALOGICAL RESEARCH OF URINARY STONES

Abstract

Introduction. The idea of using dual-energy computed tomography (DECT) originated in the early development of computed tomography (CT). However, only recently, advances in radiation diagnosis have made it possible to use dual-energy CT for routine clinical use. We describes the characteristic features of dual-energy CT scanners, as well as the results of a study of 245 patients with urolithiasis, the identification of urinary stones in vivo and the subsequent comparative characteristics with mineralogical studies of uroliths. Purpose. Evaluate the possibility of using DECT in the diagnosis of urolithiasis with the determination of the chemical composition of urinary stones in vivo. Materials and methods. A group of patients (n=245) aged 18 to 84 years was examined. All patients with the established diagnosis-urolithiasis-were treated with DECT (Somatom Definition, Siemens, Forchheim, Germany) with data processing, then in-vitro infrared spectrometry (IR-Alpha-P spectrometer) to determine the true composition of the calcu lus. Results. After conducting the DECT and then ROC analysis and comparing the results with the IR-spectrometry data, it was established that stones with an average density of less than 500 HU according to DECT can be attributed to urate, with a uric acid content of more than 50% with a sensitivity of 91,1% (34 stones of 35) and specificity of 100% — the content of uric acid is also determined in polymineral calculi with a content of less than 50%. The knowledge gained on the composition and structure of the stone in vivo can subsequently be used in pathogenetic treatment and prevention of complications in patients with urolithiasis, and influence the choice of the tactics of removing the uroliths. Conclusions. The obtained results give the right to apply DECT in the diagnosis of urolithiasis, and with high sensitivity to identify urate stones in vivo, thereby influencing the choice of the tactics of removal of uroliths and pathogenetic treatment, as well as the prevention of complications in patients with urolithiasis.