Clinical and radiological predictors of stone-free status after ureteroscopy and shock wave lithotripsy in ureteral stone: A retrospective study

Abstract

Aim: To identify clinical and non-contrast computed tomography (NCCT)-based radiological predictors of stone-free (SF) status following shock wave lithotripsy (SWL) and ureteroscopy (URS) in patients with solitary ureteral stones.

Methods: This retrospective study included 297 patients treated with SWL (n=147) or URS (n=150) between May 2022 and June 2025. Demographic, clinical, and NCCT-based parameters—stone volume, Hounsfield unit (HU), proximal ureteral diameter (PUD), skin-to-stone distance (SSD), and ureteral wall thickness (UWT)—were recorded. SF status was assessed via imaging four weeks post-treatment. Separate univariate and multivariate logistic regression analyses were performed for each group.

Results: The overall SF rates were 69% in the SWL group and 78% in the URS group. In SWL patients, lower BMI, waist circumference, stone volume, HU, PUD, and low-grade hydronephrosis were significantly associated with SF- status in univariate analysis, but none remained significant in multivariate analysis. In the URS group, younger age, smaller WC, lower stone location, and smaller stone volume were associated with higher SF rates; however, only stone volume remained significant in multivariate analysis.

Conclusion: Stone volume was identified as a consistent and independent predictor of SF status in both treatment modalities. While body composition metrics and NCCT-derived parameters such as HU and PUD showed significant associations—particularly in the SWL group—their predictive value diminished after adjustment, likely due to inter-variable interactions. These results emphasize the importance of integrating radiological and clinical factors to plan treatment decisions for patients with ureteral stones.