A.E. Shupenev1, A.V. Shcherbachev2, A.V. Sivkov3, M.Yu. Prosyannikov4, S.A. Golovanov5, D.A. Voitko6, N.V. Anokhin7, I.A. Kudashov8, A.V. Pavlov9, I.S. Korshunov10, A.N. Tikhomirov11, O.I. Apolihin12

3,4–7 N.A. Lopatkin Research Institute of Urology and Interventional Radiology – branch of the Federal State Budgetary Institution "NRMIC Radiology" of the Ministry of Health of the Russian Federation (Moscow, Russia)
1,2,8–12 Moscow Bauman State Technical University (Moscow, Russia)
1 ash@bmstu.ru

Introduction. The incidence of urolithiasis (KSD) is rapidly increasing, highlighting the need for improved diagnostic and treatment methods. An important task is to identify the causes of lithogenesis, which is currently based on a biochemical analysis of blood and urine, as well as an analysis of the chemical composition of urinary stones. However, these methods do not provide a complete picture of the activity of physicochemical processes of crystal formation.

Methods. This work proposes a new method for assessing the crystallization activity of urine, based on dynamic laser light scattering. An experimental stand has been developed using the principles of laser turbidimetry and nephelometry to analyze the optical properties of urine solutions and their phantoms. The experimental stand is equipped with a diode laser radiation source and several photodetectors, which makes it possible to evaluate the dynamics and main phases of crystal formation in urine.

Results. It has been experimentally established that the proposed method makes it possible to distinguish between urine samples from healthy and urolithiasis patients based on an assessment of the dynamics of crystal formation. In particular, it was shown that the crystallization activity of urine can be assessed through the phases of nucleation, growth and aggregation of crystals. The device showed high accuracy and the ability to reproduce results, which opens up prospects for its use in clinical practice.

Conclusion. The development of a new method and instrument for assessing the crystallization activity of urine is an important step in the diagnosis and treatment of urolithiasis. This will allow urologists not only to identify patients at high risk of stone formation, but also to test new treatment and preventive regimens and pharmaceuticals. In the future, it is planned to improve the device to optimize its use in medical institutions, which will significantly improve the diagnosis, treatment and prevention of urolithiasis.

Thus, the development of an easy-to-use and accurate prognostic model, as well as a portable device that allows real-time determination of crystallization and anti-crystallization properties of urine, will significantly improve the diagnosis, treatment and metaphylaxis of urolithiasis. In the future, it is planned to add a module with cartridges to automate research, which will make the device even more convenient and effective in clinical practice.

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