A comparison of S.T.O.N.E nephrolithometry scoring system, Guy's stone score, and Seoul National University Renal Stone Complexity (S-ReSC) in predicting mini-PCNL stone-free rate.

The main goal of the study is to evaluate the three stone scoring systems (S.T.O.N.E nephrolithometry scoring system (STONE), Guy's stone score (GSS) and Seoul National University Renal Stone Complexity (S-ReSC)) for the stone-free rate (SFR) of mini-PCNL. We retrospectively analyzed 72 patients who received mini-PCNL from February 2018 to October 2020. The SFR, complication rates, hospitalization days and recurrence rates were analyzed using three stone scoring systems. The result showed statistical significance in the association between scoring system and stone-free (STONE: OR 95%CI 0.409 (0.221-0.759), p = 0.0045; S-ReSC OR 95%CI 0.633 (0.401-0.999), p = 0.0497), but not GSS (OR 95%CI 0.776 (0.397-1.516), p = 0.4581). After adjusting the potential confounding factors, the area under curve (AUC) of STONE, GSS, and S-ReSC was 0.86, 0.78, and 0.81, respectively, and Akaike information criterion (AIC) of STONE, GSS, and S-ReSC was 64.65, 74.89, and 69.92, respectively. The accuracy rate of STONE, GSS, and S-ReSC was 0.81, 0.75, and 0.79, respectively. There was no statistically difference of predicting stone recurrence (p = 0.46, 0.53, 0.86), complications (p = 0.74, 0.51, 0.16) and hospitalization days (p = 0.77, 0.86, 0.87) in STONE, GSS, and S-ReSC, respectively. In conclusion, both the STONE and S-ReSC stone scoring systems are viable for predicting the SFR following mini-PCNL, especially after variable adjustment with the STONE system demonstrating superiority over S-ReSC.

Stone-scoring systems for predicting complications in percutaneous nephrolithotomy: A systematic review of the literature.

Objective: Percutaneous nephrolithotomy is a treatment of choice for larger stones of the upper urinary tract. Currently, several nephrolithometric nomograms for prediction of post-operative surgical outcomes have been proposed, although uncertainties still exist regarding their roles in the estimation of complications. Methods: We conducted a systematic review on PubMed and Web of Sciences databases including English studies with at least 100 cases and published between January 2010 and December 2021. We identified original articles evaluating correlations between the Guy's stone score, the stone size (S), tract length (T), obstruction (O), number of involved calices (N), and essence or stone density (E) (S.T.O.N.E.), Clinical Research Office of the Endourological Society (CROES), and Seoul National University Renal Stone Complexity (S-ReSC) scores and post-operative complications in adult patients. We also included newly designed nomograms for prediction of specific complications. Results: After an initial search of 549 abstracts, we finally included a total of 18 papers. Of them, 11 investigated traditional nephrolithometric nomograms, while seven newly designed nomograms were used to predict specific complications. Overall, 7316 patients have been involved. In total, 14 out of 18 papers are derived from retrospective single-center studies. Guy's stone score obtained correlation with complications in five, S.T.O.N.E. nephrolithometry score in four, while CROES score and S-ReSC score in three and two, respectively. None of the studies investigated minimally invasive percutaneous nephrolithotomy (PCNL) and all cases have been conducted in prone position. Considering newly designed nomograms, none of them is currently externally validated; five of them predict post-operative infections; the remaining two have been designed for thromboembolic events and urinary leakage. Conclusion: This review presents all nomograms currently available in the PCNL field and highlights a certain number of concerns. Published data have appeared contradictory; more recent tools for prediction of post-operative complications are frequently based on small retrospective cohorts and lack external validations. Heterogeneity among studies has also been noticed. More rigorous validations are advisable in the future, involving larger prospective patients' series and with the comparison of different tools.

External validation of the T.O.HO. score as predictor of success after retrograde intrarenal surgery.

BACKGROUND: To assess the effectiveness of T.O.HO. (Tallness, Occupied lesion, Houndsfield unit evaluation) score in predicting the retrograde intrarenal surgery (RIRS) success and to validate this scoring system. METHODS: The age, sex, previous stone surgery, hospitalization, surgery duration, postoperative complication, stone length, stone location, stone density, stone number, lateralization, presence of hydronephrosis, and presence of preoperative stent datas of 611 patients who underwent RIRS in our clinic between January 2013 and January 2021 were retrospectively assessed. The patients were divided into two groups as successful and unsuccessful. The T.O.HO scores of all patients were calculated. RESULTS: The success rate was 72.5%. Compared to the unsuccessful group, stone length and stone density were lower, surgery duration was shorter and there were less lower pole stones in the successful group (p < 0.001). No significant difference was found between the two groups in terms of the other parameters. The T.O.HO. score was significantly lower in the successful group compared to the unsuccessful group (p < 0.001). According to the multivariate logistic regression analysis, stone length (OR: 0.905; 95% Cl: 0.866-0.946; p < 0.001), lower pole location (OR: 0.546; 95% Cl: 0.013-0.296; p < 0.001), stone density (OR: 0.999; 95% Cl: 0.998-1; p = 0.044) and the T.O.HO. score (OR: 0.684; 95%Cl: 0.554-0.844; p < 0.001) were found as the independent risk factors for RIRS success. ROC curve analysis showed that the T.O.HO. score could predict the RIRS success with 7.5 cut-off point (AUC: 0.799, CI: 0.76-0.839; p < 0.001). CONCLUSION: The T.O.HO. score can predict RIRS success with a high rate of accuracy.