Use of the STONE Score for Predicting the Outcomes of Lithotripsy: A Narrative Review.

Urinary stone disease is a common urological condition that affects individuals across all age groups worldwide. It is traditionally more common in developed countries, but the incidence is rising in the tropics. This increase is possibly linked to climate change, increased ambient temperatures, and the adoption of westernized diets. Its occurrence is approximately twice as high in males as in females. Several systems have been formulated to help predict complications and other outcomes of lithotripsy. Examples include the STONE (Size, Topography, Obstruction, Number, Evaluation) scoring system, Clinical Research of the Endourological Society nomogram, Guy's scoring system, and Seoul National University Renal Stone Complexity. The STONE scoring system is a simple tool derived from CT findings of patients with upper urinary tract stones. It was initially designed to predict the stone-free rate in patients undergoing percutaneous nephrolithotomy. However, it was later modified for use in ureteroscopy. Multiple studies have been published that show that the score has a reasonable predictive accuracy in determining the outcomes of lithotripsy. It is comparable to the other nephrolithometric scoring systems and can serve as a useful tool in perioperative patient management. This review aims to examine the STONE scoring system, its correlation with clinical outcomes, and comparison with alternative scoring systems, ultimately assessing its importance in the management of patients with upper urinary tract stones.