Agreement Between Visual Assessment of Urinary Stones Morphology During Endo-Urological Procedure and Fourier Transform Infrared Spectroscopy- Based Composition Analysis: An Observational Study

Introduction: To assess the prediction success rate of the stone composition by visual assessment during endourological procedures in relation to stone analysis by Fourier Transform Infrared Spectroscopy. Methods: Prospectively, 150 patients undergoing endourological procedures for urolithiasis between June 2024 and July 2025 were analyzed. The senior consultant, the junior consultant, and the residents visually assessed the stone morpho-constitution (according to Daudon classification) during the endoscopic procedures. Stone samples were obtained which were analysed using Fourier transform infrared spectroscopy, and the results were correlated with the visual assessment done by the surgeon. Results: Stone analysis by Fourier transform infrared spectroscopy showed 28 (18.67%) of the stones had only one morphological type (pure stones), while 122 (81.33%) had more than one composition of stones (mixed stones). The accurate predictions for pure stones as Uric acid stones and Protein stones, were 43 (84.31%) and 5 (83.33%), respectively, whereas for Calcium Oxalate Monohydrate + Calcium Oxalate Dihydrate (mixed stones) was 126 (79.25%). The overall correct prediction was obtained in 64.44 %. The correct prediction was highest by the senior consultant 110 (73.33%), followed by the junior consultant 97 (64.67%), and the residents 83 (55.33%), respectively. Conclusions: The overall agreement between visual assessment of urinary stone morphology during endo-urological procedures and Fourier transform infrared spectroscopy–based composition analysis in this study was moderate, with a Cohen’s kappa value of 0.62