Popiolek M. et al., 2025: Advancing decision-making in shock wave lithotripsy for upper ureteral stones: the role of radiological stone impaction markers.
Marcin Popiolek 1 2, Johan Jendeberg 3, Max Olin 4, Magnus Wagenius 5, Pernilla Sundqvist 6, Mats Lidén 3
1Department of Urology, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
2Department of Urology, Örebro University Hospital, Örebro, 701 85, Sweden.
3Department of Radiology, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
4Department of Surgery, Blekinge Hospital, Karlskrona, Sweden.
5Department of Urology, Helsingborg Hospital, Helsingborg, Sweden.
6Department of Urology, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
Abstract
This work aims to evaluate whether radiological signs of stone impaction (RSSI) measured on non-contrast computed tomography (CT) can predict shock wave lithotripsy (SWL) outcomes for upper ureteral stones and to assess whether integrating these markers into an existing prediction model (the Niwa nomogram) improves predictive performance. We retrospectively analysed 256 patients treated with SWL for upper ureteral stones between 2012 and 2019. Standard stone parameters and RSSI, including ureteral wall thickness (UWT), ureteral diameters and CT attenuations above and below the stone, were assessed. Multivariable logistic regression, receiver operating characteristic (ROC) analysis, net reclassification improvement (NRI) and decision curve analysis (DCA) were used to evaluate predictive performance. The Niwa nomogram was enhanced by incorporating significant RSSI parameters and was internally validated using k-fold cross-validation. Maximum ureteral attenuation below the stone (UABSmax), ureter diameter above the stone (UDAS) and renal pelvis diameter (RPD) were found to be associated with SWL outcome. UABSmax had the highest individual predictive value (area under the curve (AUC) 0.66), while UWT showed no significant association or predictive value. Incorporating UABSmax and RPD into the Niwa nomogram (Niwa+) marginally increased AUC (0.72 vs. 0.71) but did not lead to significant improvements in NRI or DCA. In conclusion, certain RSSI- particularly UABSmax and RPD- were associated with SWL outcome but provided limited value when added to an already validated nomogram.
Urolithiasis. 2025 Jul 17;53(1):139. doi: 10.1007/s00240-025-01797-y. PMID: 40676249;
PMCID: PMC12271247
Comments 1
Very detailed data, critically evaluated and discussed – a very good paper, reviewers choice.
Until significant advances are made in extracorporeal lithotripsy, studies like this one contribute to a critical evaluation of the possibilities for improving the success rate. Compare it with a recent publication on the same topic (1). Currently, it is still advantageous if different findings can be attributed to different clinical causes, even if this is speculative until proven otherwise. I assume that it is impossible to discuss, based on clinical findings, why one radiomic or another is better suited to predicting the success of shock wave lithotripsy. I recommend Karl Popper and his work on critical rationalism (2).
1 Yang R, Zhao D, Ye C, Hu M, Qi X, Li Z. Predicting ESWL success for ureteral stones: a radiomics-based machine learning approach. BMC Med Imaging. 2025 Jul 4;25(1):268. doi: 10.1186/s12880-025-01817-8. PMID: 40615969; PMCID: PMC12228301.
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2 https://en.wikipedia.org/wiki/Critical_rationalism
Peter Alken