Development and validation of a preoperative nomogram for predicting patients with impacted ureteral stone: a retrospective analysis

Predictive value of NCCT quantitative analysis for proximal and middle impacted ureteral stones

The purpose of the study was to explore the predictive value of preoperative quantitative NCCT analysis for proximal and middle ureteral stone impaction. Data of 128 patients who diagnosed with proximal and middle ureteral stones were analyzed. Stone size, upper diameter of the ureter(D1), lower diameter of the ureter (D2), CT attenuation of the ureter above the stone (HA, 'HU above'), CT attenuation of the ureter below the stone (HB, 'HU below'), CT attenuation values of the stone's proximal segments (C1), CT attenuation values of the stone's distal segments (C2), and ureteral wall thickness(UWT)were recorded. Logistic regression was used to perform univariate and multivariate analyses of the data to determine the independent predictors of proximal and middle ureteral stone impaction. The receiver operating characteristic (ROC) curve was plotted to evaluate the predictive performance. Among the 128 patients, 52 (40.6%) had impacted stones, while 76 (59.4%) did not. Multivariate logistic regression analysis showed that stone size > 9.45 mm (OR = 1.372, 95% CI = 1.071-1.756, P = 0.012), UWT > 3.22 mm (OR = 4.217, 95% CI = 2.165 ~ 8.213, P < 0.001)、DDR > 2.10 (OR = 4.901, 95% CI = 1.797 ~ 13.365, P = 0.002)and HBA > 1.58 (OR = 5.237,95% CI = 1.502 ~ 18.259, P = 0.009)were independent risk factors for predicting ureteral stone impaction. In conclusion, stone size, UWT, DDR, and HBA show crucial predictive value for impaction of stones.

Applying urinary ultrasound to predict the risk of spontaneous ureteral stone passage: a retrospective cohort study

BACKGROUND

To assess the value of urological ultrasound in predicting the risk of spontaneous passage of ureteral stones.

METHODS

Clinical and ultrasound data were collected consecutively from patients receiving conservative treatment for ureteral stones, and the outcome of spontaneous passage was followed up for 1 month. Ultrasound variables independently associated with the risk of spontaneous stone passage were screened. A logistic regression prediction model was constructed based on the independent risk factors, and the discriminative efficacy and clinical utility of the prediction model in inferring the risk of spontaneous passing were assessed by the receiver operating characteristic (ROC) curve, calibration curve and clinical decision curve.

RESULTS

A total of 163 patients undergoing conservative treatment for ureteral stones were included in the study, with a mean age of 45.95 ± 13.01 years. Among them, 47 cases (28.83%) experienced failure of spontaneous stone passage. Multivariable analysis revealed that stone length (OR: 2.622, P = 0.027), distal stone location (OR: 0.219, P = 0.003), and ureteral jetting frequency (OR: 6.541, P < 0.001) were independent risk factors for spontaneous stone passage. A prediction model incorporating stone length, stone location, and affected ureteral jetting frequency was developed to assess the risk of spontaneous stone passage. The area under the ROC curve was 0.814 (95% CI: 0.747-0.882), indicating good discriminatory power. The prediction model also demonstrated favorable net clinical benefit.

CONCLUSION

A prediction model based on ultrasound-derived stone length, location, and ureteral jetting frequency can accurately evaluate the risk of spontaneous stone passage in patients with ureteral stones, providing a basis for optimizing the clinical decision-making on ureteral stones, and has reliable clinical application value.

The optimal management of large upper ureteral stones (> 1.5 cm) with infection in elderly patients: a comparative analysis of three minimally invasive surgical approaches

PURPOSE

The aim of this study was to investigate the efficacy and safety of three minimally invasive surgical approaches for treating large upper ureteral stones complicated by infection in elderly (> 60 years) patients.

METHODS

Clinical data from 95 elderly patients with large upper ureteral stones and infection, treated at our hospital between January 2018 and April 2023, were retrospectively analyzed. The surgical approaches included FURL (flexible ureteroscopic lithotripsy) 33 cases, mPCNL (minimally percutaneous nephrolithotomy) 29 cases, and RLUL (retroperitoneal laparoscopic ureterolithotomy) 33 cases. Surgical time, intraoperative blood loss, postoperative hospital stay, reoperation rate, incidence of postoperative complications, and hospitalization costs were observed and compared among the three groups.

RESULTS

No statistically significant difference was found in stone clearance rates among the three groups (P > 0.05). The FURL group exhibited advantages over the mPCNL and RLUL groups in surgical time, intraoperative blood loss, and postoperative hospital stay (P < 0.05). However, it also had the highest reoperation rate and hospitalization costs (P < 0.05). RLUL demonstrated superiority over the mPCNL and RLUL groups in terms of reoperation rate, incidence of complications, and hospitalization costs (P < 0.05). Notably, mPCNL exhibited the highest complication rate at 37.9% (P < 0.05).

CONCLUSION

For elderly patients with large upper ureteral stones complicated by infection, FURL, mPCNL, and RLUL represent effective surgical approaches. Further attention is needed regarding the perioperative safety of mPCNL. RLUL, which offers higher safety, efficacy, and cost-effectiveness, can be considered a primary surgical option for these patients.

Area of hydronephrosis is a useful predictive factor of impacted ureteral stones

Ureteroscopic lithotripsy for impacted stones is challenging, but it is important to predict impacted stones preoperatively. Hydronephrosis, which is evaluated by a grading system, is often apparent in impacted stones. However, the currently used grading system is a qualitative evaluation. We, therefore, focused on a quantitative evaluation: the area of hydronephrosis. The aim of this study was to investigate whether the area of hydronephrosis could predict impacted stones more accurately than Society for Fetal Urology grade. We retrospectively identified 160 patients who underwent ureteroscopic lithotripsy for ureteral stones at our hospital between January 2014 and April 2022. Impacted stones were defined as stones fixed to the ureteral wall that could not be moved by means of ureteroscopic manipulation or water pressure. Of the 160 patients, 54 (33.8%) had impacted stones. Comparing patient characteristics, there were significant differences in stone size, ureteral wall thickness, Society for Fetal Urology grade, renal pelvic width and area of hydronephrosis (all P < 0.01). Receiver operating characteristic analysis showed that area of hydronephrosis was the more significant predictive value (area under the curve 0.781) compared with Society for Fetal Urology grade (area under the curve 0.676, P < 0.01). Multivariate analysis revealed that significant independent predictive factors of impacted stones were thicker ureteral wall thickness and larger area of hydronephrosis (both P < 0.01). The area of hydronephrosis and ureteral wall thickness were significant predictors of impacted stones in patients undergoing ureteroscopic lithotripsy for ureteral stones. These factors may be useful for selecting the treatment and preoperative settings.

Development of a new scoring system predicting medical expulsive therapy success on 4-10 mm distal ureteral stones: medical expulsive therapy stone score (METSS)

Ureteral stone passage by using medical expulsive therapy (MET) are affected by numerous radiological and clinical parameters. We aimed to construct a scoring system, which would be based on clinical and computed tomography (CT)-derived data, to predict the success of the MET approach. 186 patients presenting to urology clinic or emergency department with unilateral single 4-10 mm distal ureteral stone and who had MET were included. All patients were divided into two groups as the MET-successful group and the MET-unsuccessful group. The success rate of MET was 67.2%. Stone size ≥ 6.5 mm, stone density > 1078 HU, ureteral wall thickness (UWT) > 2.31 mm, ureteral diameter (UD) > 9.24 mm, presence of periureteral stranding (PUS) and presence of diabetes mellitus (DM) were stated as the independent risk factors. Based on the regression coefficients on multivariate logistic regression analysis, 1 point for stone size > 6.5 mm, 2 points for stone density > 1078 HU, 2 points for UWT > 2.31 mm, 3 points for UD > 9.24 mm, 1 point for presence of PUS and 1 point for presence of DM were assigned to patients for each risk factor. Higher medical expulsive therapy stone score (METSS) indicated lower MET success. All patients were classified into three risk groups according to METSS: low risk (0-3 points; success percentage: 92.8%); intermediate risk (4-5 points; success percentage: 60.4%) and high risk (6-10 points; success percentage: 8.3%). The METSS seems to separate successfully the patients with a favorable or adverse constellation of factors.

Comprehensive endoscopic management of impacted ureteral stones: Literature review and expert opinions

Treatment of urolithiasis, a benign disease, requires high efficacy and safety. Endoscopic treatment of impacted ureteral stones remains a challenging procedure for urologists, despite recent remarkable advances in surgical technology in treatment of urolithiasis. The success rate of endoscopic treatment in patients with impacted stones is reported to be lower than that in patients with nonimpacted stones. Moreover, the presence of stone impaction is associated with high rates of intraoperative and postoperative complications. The best management for patients with impacted ureteral stones should therefore be devised based on the latest knowledge and techniques. The present review focuses on the preoperative prediction of stone impaction, the safest and most effective endoscopic surgical procedures, and the most appropriate management for postoperative ureteral strictures. We overview comprehensive endoscopic management for impacted ureteral stones based on literature review and expert opinions.