Assessment of Factors Responsible for Stone-Free Status After Retrograde Intrarenal Surgery.

Aim The study aimed to evaluate the predictive factors that determined stone-free rate (SFR) after retrograde intrarenal surgery (RIRS). Materials and methods This prospective study was conducted on 183 patients undergoing RIRS for renal stones. Patients were categorized into two groups, depending on stone-free status one month following the procedure. SFR was defined as the complete absence of stones or stones <4 mm. The parameters studied included patient demographics, presence of hydronephrosis, presence of preoperative double J-stent, abnormal renal anatomy, and stone characteristics (stone burden, stone number, stone density, stone location, lower pole infundibulopelvic angle, and lower pole renal infundibular length (RIL)). Univariate and multivariate analyses were performed to identify risk factors for residual stones. We assessed the predictive ability of the RIRS score and Resorlu-Unsal stone score (RUSS) for evaluating SFR utilizing receiver operating characteristic (ROC) analysis. Results 183 patients were included in the study with a median age of 51 years. 131 (71.6%) patients were declared stone-free after the procedure. The mean stone size and density were 16.9 SD±7.5 mm and 1038 SD±342 Hounsfield units (HU) respectively. Stone-free patients had lower stone size (14.3 mm vs. 23.6 mm, p<0.01) and stone density (970 HU vs. 1211 HU, p<0.01) compared to non-stone-free patients. Patients with residual stones had steeper lower pole renal infundibulopelvic angle (RIPA) (31.3° vs. 40.7°, p<0.01) and longer RIL (26.6 mm vs. 21.1 mm, p<0.01). Stone multiplicity (p<0.01), lower pole stone location (p<0.01), and renal malformations (p<0.01) were significant influencing factors for residual renal stones after RIRS. Multivariate analysis revealed stone size, stone density (HU), and stone location as independent predictors for SFR after RIRS. Among the scoring systems, the RIRS score had the highest diagnostic accuracy for SFR (area under the curve (AUC): -0.882, 95% CI-0.828-0.936). Conclusion Stone size, stone density (HU), and stone number are important predictors of SFR after RIRS. Lower pole stone location and abnormal renal anatomy play a substantial role in determining SFR after RIRS. In lower pole stones, a long RIL and acute RIPA negatively influence SFR. Additionally, the RIRS score was found to be a better predictor for SFR than the RUSS score.

Comparative Analysis of Standard Percutaneous Nephrolithotomy (PCNL) and Mini-Percutaneous Nephrolithotomy (Mini-PCNL) for Renal Stones Larger Than 2 cm at a Rural Hospital: A Study Protocol.

Background Percutaneous nephrolithotomy (PCNL) is considered a standard treatment option for large-size renal stones but is associated with drawbacks such as bleeding and prolonged recovery. Mini-PCNL offers a less invasive alternative, but its efficacy compared to standard PCNL for renal stones larger than 2 cm remains under debate. This study aims to compare the efficacy and safety of standard PCNL versus mini-PCNL for renal stone sizes more than 2 cm. Methods This single-centre prospective interventional study will be conducted at Acharya Vinoba Bhave Rural Hospital (AVBRH). The study will include patients 18 to 70 years of age undergoing unilateral PCNL for renal calculi. Patients with renal stones larger than 2 cm will be enrolled. Data on stone-free rate (SFR), operative duration, hospital stay time, surgical site infection, haemoglobin (Hb) drop, need for blood transfusion, and post-surgery fever will be collected and compared between the two procedures. Statistical analysis of data will be performed using descriptive and analytical statistics. Results The study aims to enrol a total of 32 patients. Data analysis will be done using IBM SPSS Statistics for Windows, Version 24 (Released 2016; IBM Corp., Armonk, New York). Conclusion This study will provide valuable insights into the comparative outcome in terms of efficacy and safety of standard PCNL and mini-PCNL for kidney stones larger than 2 cm.

Comparison of laparoscopic ureterolithotomy, retrograde flexible ureteroscopy, and mini-percutaneous antegrade flexible ureteroscopic lithotripsy for treating large (≥ 15 mm) impacted proximal ureteric stones: a prospective randomized trial.

The purpose of this study is to compare the outcomes of transperitoneal laparoscopic ureterolithotomy (TPLU), retrograde flexible ureteroscopy (R-fURS), and mini-percutaneous antegrade flexible ureteroscopy (A-fURS) for treating large (≥ 15 mm) impacted proximal ureteral stones. A total of 105 adult patients were randomized into 3 equal groups: group A (35) patients underwent TPLU, group B (35) patients underwent R-fURS, and group C (35) patients underwent A-fURS. The initial stone-free rate was 100%, 68.6%, and 80% in groups A, B, and C, respectively. The mean operative time (OT) was (85.0 ± 7.57 min) in group A, (61.0 ± 8.21 min) in group B, and (89.57 ± 15.12 min) in group C. The three groups were comparable concerning the overall complications. R-fURS is a less invasive modality for treating such stones; however, it is associated with a lower SFR and a higher rate of auxiliary procedures. Both TPLU and miniperc A-fURS are effective and valuable alternatives for treating large impacted proximal ureteric stones.

FIRE Stones: impact of forced diuresis on the residual fragment rate after flexible ureteroscopy for destruction of kidney stones with laser-protocol for a randomized controlled two-parallel group multicenter trial with blinding evaluation.

BACKGROUND: Lithiasis is a common and recurrent disease. Flexible ureteroscopy (fURS) is the cornerstone of laser treatment of kidney stones. Kidney stones destruction requires its laser pulverization into small fragments in order to remove them through the ureter or improve their spontaneous expulsion along the urinary tract. However, most of the time, all the micro-fragments and dust created cannot be extracted using our surgical tools and may stay intra-renally at the end of the procedure. Adjuvant treatments (such as forced diuresis, inversion or mechanical pressure) were previously described to improve the expulsion of stone fragments after extra-corporeal shock wave lithotripsy. Nevertheless, the impact of adjuvant treatment after fURS remains unclear and mainly theoretical. OBJECTIVE: The primary objective is to show that the injection of 40 mg of furosemide in slow intravenous during 10 min, after the procedure, increases the stone-free rate 3 months after a fURS for destruction of kidney stones with laser. METHODS/DESIGN: The study will be a two-parallel group randomized, controlled, multicentric trial with a blinding evaluation. Nine French departments of urology will participate. Patients will be randomized in 2 groups: the experimental group (injection of 40 mg of furosemide at the end of the surgery) and a control one (usual care). Patients will be followed up for 3 months (± 2 weeks) after the surgery. Then, we will perform a low dose abdomino-pelvic CT scan. The primary outcome is the stone-free rate at 3 months. A centralized review of the images will be performed by two specialized radiologists, in a blind and crossed way to allow a homogenization of the results. The secondary outcomes will include the rate of early post-operative urinary tract infection (UTI), the evaluation of post-operative pain, and the safety of the use of furosemide in patients treated by fURS for renal stone laser destruction. As secondary objectives, it is also planned to look at the effect of the prescription of an alpha-blocker as usual treatment on stone-free rate and to assess the agreement between the imaging analysis of the urologist and the specialized radiologist. DISCUSSION: Lithiasis is a public health problem. It affects about 10% of the general population. This prevalence is increasing (multiplied by 3 in 40 years), partly due to changes in the population's eating habits over the years. The lithiasis patient is a patient with a chronic disease requiring annual follow-up and who may suffer from multiple recurrences, with a recurrence rate at 5 years of 50%. Recurrences are partly due to residual fragments left in the kidneys at the end of the operation. Other risk factors for recurrence include dietary hygiene and the presence of an associated metabolic disease. The metabolic blood and urine tests recommended by the Association Française d'Urologie (AFU) can be used to manage these last two problems. As far as residual fragments are concerned, their presence leads to an early recurrence of stones because they form the bed for a new aggregation of crystals in the kidneys. Being able to reduce the rate of residual fragments in patients with the use of furosemide at the end of the intervention therefore seems essential in the management of recurrences in our patients. This will also improve our patients' quality of life. Indeed, lithiasis disease leads to chronic pain associated with acute pain that motivates consultations to the emergency for specialized management. This study is the first to evaluate the impact of forced diuresis with the use of furosemide on the stone-free rate after a fURS for destruction of kidney stone with laser. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05916963 , first received: 22 June 2023. EU Clinical Trials Register EudraCT Number: 2022-502890-40-00.

Endoscopic combined intrarenal surgery versus percutaneuos nephrolithotomy for complex pediatric stone disease: A comparative analysis of efficacy and safety.

INTRODUCTION: Decision-making for complex pediatric urinary system stone disease is still a challenge for pediatric urologists. The interest in supine percutaneous nephrolithotomy (PCNL) is increasing among centers to achieve high surgical success rates with less morbidity. Despite advanced retrograde intrarenal surgery armamentarium, percutaneous approaches remain the first-line surgical treatment modality for >2 cm and complex renal stones. There are no comparative studies yet in the literature for pediatric endoscopic combined intrarenal surgery (ECIRS) OBJECTIVE: In this study, we aimed to contribute to the literature by evaluating the safety and efficacy of ECIRS by comparing it with PCNL. STUDY DESIGN: Patients under 18 years of age who underwent PCNL and ECIRS for urinary tract stone disease at our Pediatric Urology department between 2012 and 2024 were included. Preoperative (demographic characteristics, stone characteristics, biochemical parameters), perioperative (duration of surgery, number of accesses, lasing and fluoroscopy times, endoscopic and fluoroscopic stone-free rates) and postoperative (hospital stay, urinary tract infection, complication and radiological stone-free rates) parameters were retrospectively evaluated. RESULTS: A total of 68 children [28 (41%) girls and 40 (59%) boys] aged 5 (0-17) years were included in the study. ECIRS was performed in 19 (28%), supine in 28 (41%) and prone PCNL in 21 (30%) patients. Age (p = 0.029), Guy's stone score (p < 0.001), S.T.O.N.E. (p < 0.001), and Seoul National University Renal Stone Complexity (S-ReSC) scores (p = 0.001) for preoperative parameters were found to be higher in ECIRS group over both PCNL methods (Summary Table). However, Clinical Research Office of the Endourological Society (CROES) score was seen lower for ECIRS group patients compared to other groups (p = 0.028). Surgery time (in favor of supine over prone PCNL), fluoroscopy time (in favor of ECIRS and Supine PCNL over Prone PCNL), preferred laser type (prone PCNL group was mostly performed with holmium laser, whereas other groups were balanced between Holmium and Thulium Fiber Laser) and exit strategy (the preferred exit strategy was DJ Stent in most of the ECIRS patients, whereas nephrostomy tube was used in some of the PCNL group) showed significant difference among the groups as perioperative parameters (p = 0.042, <0.001, <0.001, <0.001, respectively). Surgery time was lower for supine PCNL compared to prone PCNL. For postoperative parameters, stone-free rates, complication rates and urinary tract infections were similar between the 3 groups, while a difference was detected in terms of length of hospital stay in favor of ECIRS over both supine and prone PCNL (p = 0.006). DISCUSSION: The current trial suggests that stone-free and complication rates of ECIRS and supine PCNL were similar in the pediatric complex stone patients. Although, the stones in the ECIRS group we found to be more complex. Also, ECIRS was superior to PCNL in terms of fluoroscopy exposure and hospital stay. CONCLUSION: With the widespread use of new generation ureteral access sheaths and flexible ureterorenoscopes, ECIRS may have an important role in treatment of complex pediatric kidney stones.

Comparison of Swiss LithoClast Trilogy™ and Pneumatic Swiss LithoClast™ in Mini-Percutaneous Nephrolithotomy in Terms of Stone Free Rate and Complications: A Single-Center Experience From a Stone Belt Country.

Background Renal calculi therapy has advanced significantly in recent years, with mini-percutaneous nephrolithotomy (PCNL) emerging as a minimally invasive treatment modality. Mini-PCNL has been subjected to several modifications to achieve the best possible outcomes and reduce morbidity. This study aimed to compare the efficacy and safety of Swiss LithoClast Trilogy™ and pneumatic Swiss LithoClast™ in managing renal stones with mini-PCNL. Methodology This descriptive retrospective study was conducted at the Department of Urology, Lady Reading Hospital, from January 1, 2023, to December 31, 2023. A record of male and female patients aged more than 18 years who underwent mini-PCNL for renal stones was retrieved. The following two groups of patients were created: group A (n = 25) mini-PCNL with Swiss LithoClast Trilogy™ and group B (n = 26) mini-PCNL with pneumatic Swiss LithoClast™. The efficacy and safety profile of both groups was compared. Results A total of 51 patients were enrolled, with 25 in group A and 26 in group B. Groups A and B had mean ages of 45.2 and 47.5 years, respectively. Male participants outnumbered females in both groups, 72% (n = 18) in group A and 77% (n = 20) in group B. Group A had a mean stone size of 15.8 mm, and group B had a mean stone size of 16.5 mm. Stone-free rate on postoperative day one was 88% (n = 22) in group A and 84.6% (n = 22) in group B, with no statistically significant difference (p > 0.05). At the end of three months, 96% of participants in group A and 84.6% of patients in group B were found to be free of stones, and the difference between the two groups was not statistically significant (p > 0.05). Intraoperative hemorrhage occurred in 12% (n = 3) of group A and 15.4% (n = 4) of group B patients, with no significant difference (p > 0.05). Conclusions There were no significant differences in stone-free rates, complication rates, or intraoperative/postoperative complications between mini-PCNL with Swiss LithoClast Trilogy™ or Pneumatic Swiss LithoClast™.

Sedation vs. general anesthesia in stone ureteroscopy: Comparison of efficacy and safety, a post COVID-19 report.

INTRODUCTION: Ureterorenoscopy (URS) for ureteral or renal stones is traditionally performed under general anesthesia (GA). Sedation is an alternative to GA, allowing control of the level of consciousness, spontaneous ventilation, and faster recovery. Our aim was to compare sedation and GA for patients undergoing ureterorenoscopy. Endpoints were stone-free rate (SFR) and complication rates. METHOD: Monocentric comparative retrospective study including all consecutive ureterorenoscopies for ureteral or renal stone. The inclusion period was dichotomized in two 6-months periods due to the COVID-19 pandemic: from January 1 to July 1, 2019 (URS under GA) and from January 1 to July 1, 2021 (URS under GA or sedation). Stone-free (SF) status was defined as the absence of stone or fragment>4mm after the first ureterorenoscopy. Complication rates were assessed according to the Satava (perioperative complications) and Clavien-Dindo (postoperative complications) classifications. Statistical analysis was performed by Chi-square test. RESULTS: A total of 185 patients were included for a total of 206 ureterorenoscopies; 82 underwent ureterorenoscopy under GA and 103 under sedation. The median stone size was 10 [7-16] mm. In all, 150 (81%) patients had at least one intrarenal stone. The SFR was similar between the two groups (67% GA group, 69% sedation group, P=0.912). In the sedation group, the mean SFR in ureter was 83.7% vs. 92.5% in the GA group. In renal cavities, the mean SFR was 46.4% in the sedation group vs. 42.5% in the GA group. Satava grade I, IIa, and IIb complications were 5 (6%), 5 (6%), and 1 (1%) in the GA group and 6 (6%), 1 (1%), and 3 (3%) in the sedation group, respectively (P=0.214). The grade I, II, III, and IV Clavien complications were 6 (7%), 3 (4%), 0 (0%), and 2 (2%) in the GA group and 6 (6%), 4 (4%), 1 (1%), and 4 (4%) in the sedation group, respectively (P=0.928). CONCLUSION: Our post COVID-19 study showed no difference in efficacy and safety between ureterorenoscopy under sedation and GA for patients with renal stones. Our results confirm the interest of the sedation procedure, particularly in the context of outpatient surgery.

Prognostic Factors for Residual Lithiasis in Patients With Staghorn Calculi Undergoing Percutaneous Nephrolithotomy in the Maya Region of Yucatan, Mexico: A Case-Control Study.

BACKGROUND: Yucatan stands out as the state with the highest prevalence of urolithiasis in Mexico, placing significant demands on healthcare services, such as consultation and surgical intervention. Staghorn calculi are related to recurrent urinary tract infections, and their management is always surgical. The stone-free rate is a parameter used to measure the success of surgery, with residual stones considered those persisting four weeks after surgical management. There are understudied prognostic factors that can predict the success of achieving stone-free status, taking into account the number of stones, their location, and the anatomical variations of the patient's collecting system. The study aims to determine the prognostic factors for residual lithiasis in patients with staghorn calculi treated with percutaneous nephrolithotomy at the High Specialty Regional Hospital of the Yucatan Peninsula. METHODS: A case-control study was performed including 188 patients, aged 18 years or older, and diagnosed with staghorn calculus from January 2022 to June 2023, grouping the patients according to their stone-free rate evidence on postoperative computed tomography. Data were collected from the records of the Urology Department at a high-specialty hospital in Yucatan. The groups were analyzed, aiming to establish an association between preoperative factors and postoperative outcomes measured in terms of stone-free rate. RESULTS: A total of 188 patients with staghorn calculi were included, with a predominance in females (58.5%) and a mean age of 45.4 ± 11.9 years. The most common comorbidity was hypertension (29.8%), and 27.7% had a history of recurrent urinary tract infections. Regarding the Sampaio classification, B1 was the most prevalent in our population with 66 cases (35.1%), while Type A2 was the least common (13.8%). According to what was obtained through the multivariate logistic regression model, the calyceal anatomy Type A1 and A2 were associated with residual lithiasis (p= 0.016 OR: 2.994 CI: 1.223-7.331), and Grade IV was associated with a higher rate of residual lithiasis (p=0.005 CI: 1.586-13.100). A statistically significant association was found between stone burden and the presence of residual lithiasis (p=< 0.001). CONCLUSION: Guy's Score Grade IV showed a higher incidence of residual lithiasis, seemingly associated with stone burden, leading to the conclusion that both factors were categorized as predictors for the development of post-surgical residual lithiasis. Regarding anatomical variations according to Sampaio, it was observed that types A1 and A2 showed a lower rate of stone-free status. Therefore, we also consider them as variables that may influence the achievement of success in endourological management. Personalized patient assessment allows for more accurate prognostic factors, enabling a more comprehensive surgical planning in the presence of staghorn calculi.

Ureteroscopy for urolithiasis in bedridden patients: it is feasible and acceptable.

PURPOSE: To investigate the safety of transurethral ureteroscopy (URS) for urolithiasis in bedridden patients and to identify bedridden patient-specific risk factors for postoperative complications. METHODS: The patients who underwent URS for urolithiasis were divided into bedridden patients and good performance status (PS) patients, and the groups were compared regarding their clinical characteristics and postoperative complications. A multivariable logistic regression analysis was performed to evaluate independent predictors of postoperative febrile urinary tract infection (fUTI). RESULTS: A total of 1626 patients were included, 276 in the bedridden patient group, and 1350 in the good PS patient group. The bedridden patient group had a significantly higher age and higher proportion of females and had multiple comorbidities. In 77 patients (27.9%), 88 postoperative complications developed for the bedridden patient group. Clavien-Dindo grade III or IV complications were observed in only 8 patients. No grade V complications were observed. The most common complication was fUTI. The frequency of fUTI with grade III or IV for the bedridden patient group (2.2%) was higher compared with the good PS patient group (0.5%), but the difference was not statistically significant (p = 0.13). Bedridden patient-specific risk factors for fUTI included female sex, diabetes mellitus, cerebrovascular comorbidities, lower extremity contracture, and prolonged operative time. CONCLUSION: URS for urolithiasis is a feasible and acceptable procedure in bedridden patients, despite the moderate rate of postoperative complications. The identified risk factors provide a framework for risk stratification and individualized care in this unique patient population.

Develop a radiomics-based machine learning model to predict the stone-free rate post-percutaneous nephrolithotomy.

Radiomics and machine learning have been extensively utilized in the realm of urinary stones, particularly in forecasting stone treatment outcomes. The objective of this study was to integrate clinical variables and radiomic features to develop a machine learning model for predicting the stone-free rate (SFR) following percutaneous nephrolithotomy (PCNL). A total of 212 eligible patients who underwent PCNL surgery at the Second Affiliated Hospital of Nanchang University were included in a retrospective analysis. Preoperative clinical variables and non-contrast-enhanced CT images of all patients were collected, and radiomic features were extracted after delineating the stone ROI. Univariate analysis was conducted to identify clinical variables strongly correlated with the stone-free rate after PCNL, and the least absolute shrinkage and selection operator algorithm (lasso regression) was utilized to screen radiomic features. Four supervised machine learning algorithms, including Logistic Regression, Random Forest (RF), Extreme Gradient Boosting (XGBoost), and Gradient Boosting Decision Tree (GBDT), were employed. The clinical variables with strong correlation and screened radiomic features were integrated into the four machine learning algorithms to construct a prediction model, and the receiver operating curve was plotted. The area under the receiver operating curve (AUC), the accuracy rate, the specificity, etc., were used to evaluate the predictive performance of the four models. After analyzing postoperative statistics, the stone-free rate following the procedure was found to be 70.3% (n = 149). Among the various clinical variables examined, factors, such as stone number, stone diameter, stone CT value, stone location, and history of stone surgery, were identified as statistically significant in relation to the stone-free rate after PCNL. A total of 121 radiomic features were extracted, and through lasso regression, 7 features most closely associated with the stone-free rate post-PCNL were identified. The predictive accuracy of different models (Logistic Regression, RF, XGBoost, and GBDT) for determining the stone-free rate after PCNL was evaluated, yielding accuracies of 78.1%, 76.6%, 75.0%, and 73.4%, respectively. The corresponding area under the curve AUC (95%CI) were 0.85 (0.83-0.89), 0.81 (0.76-0.85), 0.82 (0.78-0.85), and 0.77 (0.73-0.81), positioning these models among the top performers in logistic regression prediction. In terms of predictive importance scores, the key factors identified by the logistic regression model were number of stone, zone percentage, stone diameter, and surface area. Similarly, the RF model highlighted number of stone, stone CT value, stone diameter, and surface area as the top predictors. Among the four machine learning models, the logistic regression model demonstrated the highest accuracy and discrimination ability in predicting the stone-free rate following PCNL. In comparison to XGBoost and GBDT, RF also exhibited superior accuracy and a certain level of discrimination ability. However, based on the performance of all four models, logistic regression is more likely to aid in clinical decision-making by assisting clinicians in diagnosing PCNL in patients. This enables us to effectively predict the presence of residual stones post-surgery and ultimately select patients who are suitable candidates for PCNL.

Effects of hydronephrosis on the surgical outcomes of fluoroscopically guided supine percutaneous nephrolithotomy.

PURPOSE: To evaluate the effect of hydronephrosis on operation success and the development of complications in supine percutaneous nephrolithotomy (PCNL). METHODS: A total 259 patients were included in the study who underwent supine PCNL in our clinic between September 2019 and November 2023. The patients were divided into four groups: normal, mild, moderate and severe, according to their preoperative hydronephrosis degrees. Demographic data, kidney stone characteristics, clinical aspects, surgical findings, and postoperative complications were compared across groups. RESULTS: In terms of American Society of Anesthesiologists score, stone-free rate, operation time, fluoroscopy time, and Clavien-Dindo classification grades, a statistically significant difference was found between the hydronephrosis groups. The stone-free rate in the normal, mild, moderate, and severe groups was 86.6, 82.5, 76.0, and 61.5, respectively. The severe hydronephrosis group varied statistically substantially from the other hydronephrosis groups in terms of stone-free rate, according to the post-hoc analysis. In terms of Clavien-Dindo classification grades, the severe hydronephrosis group varied statistically significantly from the normal and mild hydronephrosis groups (p values 0.04, 0.02, respectively). In terms of Clavien-Dindo classification grades, no statistically significant difference was seen between the severe and moderate hydronephrosis groups (p = 0.085). CONCLUSION: The findings of this study demonstrated that the existence of hydronephrosis was a predictive factor for the occurrence of complications and decreased the success rate of supine PCNL. Furthermore, univariate and multivariate analyses showed that the presence of hydronephrosis was a predictive factor for PCNL success and the development of complications.

Comparison of STONE Score, Guy's Stone Score, CROES Nomogram, and Seoul National University Renal Stone Complexity Score in Prognosticating Outcomes of Multiple-Tract Mini-Percutaneous Nephrolithotomy: A Retrospective Study.

Objective  The objective of this study was to compare the STONE score (Size of the stone, Topography or location, degree of Obstruction of the urinary system, Number of stones, and Evaluation of Hounsfield units), Guy's stone score (GSS), Clinical Research Office of the Endourological Society (CROES) nomogram, and Seoul National University Renal Stone Complexity Score (RSCS) in prognosticating multiple tract mini-percutaneous nephrolithotomy (mPCNL) outcome. Methodology This descriptive retrospective analysis was carried out at the Urology Department, Lady Reading Hospital, Peshawar, Pakistan. Male and female patients in the age range of 18-70 years who underwent multiple tract mPCNL for renal stones from July 1, 2021, to June 30, 2023, were included in the analysis. Results  A total of 110 patients were registered. Stone-free status (SFS) was achieved in 78.2% (n=86), and complications were observed in 13.6% (n=15) patients. The odds ratio for STONE score, GSS, CROES scoring system, and RSCS for predicting the SFS was 7.093 (95%CI 2.40-20.89), 9.333 (95%CI 2.92-29.81), 11.70 (95%CI 2.56-53.38) and 3.450 (95%CI 1.25-9.53), respectively. Conclusion  Multiple tract mPCNL is a safe and effective technique for the management of renal stones, producing a high stone-free rate. This study demonstrated adequate efficacy and dependability of the four scoring systems in predicting SFS.

Actively extracting kidney stones combined dusting technique can improve SFR of moderate-complexity kidney stones in fURL.

PURPOSE: To evaluate the necessity and effectiveness of actively extracting kidney stones with different complexity that have been visually dusted in flexible ureteroscopic lithotripsy (fURL). METHODS: We retrospectively reviewed the medical records of patients who underwent fURL with dusting technique in established hospitals. A total of 535 cases were divided into the dusting group or the dusting plus basketing group according to the use of stone basket. Their characteristics and operative parameters were collected and analyzed. We used the R.I.R.S. scoring system to classify the complexity of kidney stones and divided these kidney stones into three subgroups, namely, mild-, moderate-, and severe-complexity group. And then, the effectiveness of stone basket in these subgroups was analyzed. RESULTS: Although using a stone basket significantly reduced re-operation rate (17.8% in dusting group versus 10.2% in dusting plus basketing group, p = 0.013), no significant difference on stone-free rate (SFR) and overall incidence of complications were noticed between groups. After we classified the complexity of kidney stones using the R.I.R.S. scoring system, we found a stone basket was helpful to improve SFR in kidney stones with moderate-complexity that had been visually dusted in fURL (73.5% in dusting group versus 87.3% in dusting plus basketing group, p = 0.002) but had limited influence on SFR in mild (93.8% in dusting group versus 92.6% in dusting plus basketing group, p = 0.783) or severe (28.5% in dusting group versus 34.0% in dusting plus basketing group, p = 0.598)-complexity kidney stones. CONCLUSION: The use of stone basket should be encouraged in moderate-complexity kidney stones which can be visually dusted in fURL.

Retrograde intrarenal surgery for asymptomatic incidental renal stones: a retrospective, real-world data analysis.

OBJECTIVE: To determine surgical outcomes and stone-free rates (SFRs) when offering upfront retrograde intrarenal surgery (RIRS) to patients with asymptomatic incidental renal stones (AIRS), as active surveillance, shockwave lithotripsy or upfront intervention in patients with AIRS is still a debate among urologists. PATIENTS AND METHODS: This retrospective FLEXible Ureteroscopy Outcomes Registry (FLEXOR), supported by the Team of Worldwide Endourological Researchers (TOWER), examines adult patients who underwent RIRS. We analysed a subset of asymptomatic patients with renal stones on imaging who were treated with RIRS. Data includes patient characteristics, stone specifications, anaesthesia type, perioperative details, complications, and SFR. A multivariable logistic regression analysis was performed to assess factors associated with the SFR. RESULTS: Among 679 patients with AIRS, 640 met the inclusion criteria. The median age was 55 years, with 33.4% being female. In all, 22.1% had positive urine cultures. The median stone diameter was 12 mm, commonly in lower and interpolar locations. RIRS was preferentially performed under general anaesthesia using a reusable scope in 443 cases. Prophylactic antibiotics were administered to 314 patients. The median operation time was 58 min and the median laser time was 24 min. The SFR was 68.8%. The use of holmium laser (odds ratio [OR] 0.21, 95% confidence interval [CI] 0.06-0.63; P < 0.01) and multiple stones (OR 0.38, 95% CI 0.19-0.76; P < 0.01) were factors associated with lower odds of being stone free. Overall complications were minimal, with sepsis in 1.6% of patients. Re-interventions were performed in 76 cases (11.8%), with RIRS being the most common in 67 cases (10.6%). CONCLUSION: Our multicentre real-world study is the first of its kind that highlights the pros and cons of offering RIRS to patients with AIRS and demonstrates a favourable SFR with acceptable complications. Pre-emptively discussing potential re-intervention helps patients make informed decisions, particularly in cases involving large and multiple stones.

Thulium Fiber Laser Versus Holmium:Yttrium Aluminum Garnet for Lithotripsy: A Systematic Review and Meta-analysis.

CONTEXT: Thulium fiber laser (TFL) emerged as a competitor of holmium:yttrium aluminum garnet (Ho:YAG) laser for the treatment of urinary stones. OBJECTIVE: To compare the efficacy between Ho:YAG and TFL for laser lithotripsy of renal and ureteral stones. EVIDENCE ACQUISITION: A literature search was conducted using PubMed/Medline, Embase, and Web of Science databases to identify reports published until May 2023. The Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were followed to identify eligible studies. The primary outcome was to compare the stone-free rate (SFR) between Ho:YAG and TFL for laser lithotripsy. EVIDENCE SYNTHESIS: Eleven studies met our inclusion criteria, and data from 1286 and 880 patients who underwent, respectively, Ho:YAG and TFL laser lithotripsy were reviewed. Most studies included ureteroscopy (URS) and retrograde intrarenal surgeries as procedures, two included percutaneous nephrolithotomy, and one included URS exclusively. Only two studies reported results in pediatric patients. TFL was associated with a higher SFR (odds ratio [OR] 1.84, 95% confidence interval [CI]: 1.06-3.20; p = 0.031) when no residual fragment is considered, but not when SFR refers to the presence of fragments <3 mm (OR 2.48, 95% CI: 0.98-6.29; p = 0.055) or when only Ho:YAG with MOSES is considered (p = 0.068). According to the stones' location, TFL was associated with higher SFRs than Ho:YAG for renal (OR 3.14, 95% CI: 1.69-5.86; p < 0.001) but not for ureteral (p = 0.8) stones. TFL was associated with a lower intraoperative complication rate (OR 0.34, 95% CI: 0.19-0.63; p < 0.001). No difference was found in major (p = 0.4) or overall (p = 0.4) complication rate, operative time (p = 0.051), and laser time (p = 0.9). CONCLUSIONS: TFL is a promising laser for the treatment of urinary stones with some advantages over Ho:YAG. Further high-quality studies are needed to confirm these findings and optimize the surgical settings. PATIENT SUMMARY: The use of thulium fiber laser rather than holmium:yttrium aluminum garnet permits to reach a higher stone-free rate in stones located in the kidney rather than in the ureter.

Comparison of percutaneous nephrolithotomy and flexible ureterorenoscopy in the treatment of single upper ureteral calculi measuring 1 to 2 centimeters: a retrospective study.

PURPOSE: To compare the efficacy and safety of micropercutaneous nephrolithotomy (MPCNL) and flexible ureteroscopy (FURS) in the treatment of single upper ureteral calculi measuring 1 to 2 centimeters. METHODS: This study is a retrospective analysis that combines a review of medical records with an outcomes management database. A total of 163 patients who underwent MPCNL and 137 patients who had FURS were identified between January 2017 and December 2021. Demographic data, operation time, hospitalization time, stone-free rate, and complication rate were collected and analyzed. RESULTS: Preoperative general data of sex, age, BMI, serum creatinine, time of stone existence, stone hardness, stone diameter, preoperative hydronephrosis, and preoperative infection of the MPCNL group have no statistically significant difference with that of the FURS group. All MPCNL or FURS operations in both groups were successfully completed without any instances of reoperation or conversion to another surgical procedure. Patients who underwent MPCNL had a considerably reduced operation time (49.6 vs. 72.4 min; P<0.001), but a higher duration of hospitalization (9.1 vs. 3.9 days; P<0.001) compared to those who underwent FURS. The stone-free rate in the MPCNL group was superior to that of the FURS group, with a percentage of 90.8% compared to 71.5% (P<0.001). There was no statistically significant disparity in the rate of complications between the two groups (13.5% vs. 15.3%; P = 0.741). CONCLUSION: Both MPCNL and FURS are viable and secure surgical choices for individuals with solitary upper ureteral calculi measuring 1 to 2 cm. The FURS procedure resulted in a shorter duration of hospitalization compared to MPCNL. However, it had a comparatively lower rate of successfully removing the stones and required a longer duration for the operation.There were no substantial disparities observed in the complication rate between the two groups.FURS is the preferable option for treating uncomplicated upper ureteral calculi, whereas MPCNL is the preferable option for treating complicated upper ureteral calculi.Prior to making treatment options, it is crucial to take into account the expertise of surgeons, the quality of the equipment, and the preferences of the patient. TRIAL REGISTRATION: No.

Laparoscopic pyelotomy combined with ultrasonic lithotripsy via a nephroscope for the treatment of complex renal stones.

The purpose of the study was to introduce a novel surgical approach of combining laparoscopic pyelotomy with ultrasonic lithotripsy via a nephroscope for the treatment of complex renal stones. Between May 2021 and April 2023, 32 patients underwent laparoscopic pyelotomy combined with ultrasonic lithotripsy via a nephroscope and their perioperative variables were retrospectively collected and outcomes were assessed. Dissection and incision of the anterior renal pelvis wall was performed via a laparoscope. A 19.5 F nephroscope was introduced into the renal pelvis through a laparoscopic trocar from the incision. Stones were fragmented and sucked out using a 3.3 mm ultrasonic probe placed through the nephroscope. All operations were completed successfully and the stone-free rate at 3 days after operation was 87.5% (28/32). Four (12.5%, 4/32) patients with staghorn stones had a small residual stone in the lower calyx after operation and did not require reintervention. No patient required perioperative transfusion and four (12.5%, 4/32) patients with struvite stones developed postoperative fever, which was successfully treated with intravenous antibiotics. The mean follow-up time was 14.0 ± 7.2 months, with no patient developing long-term complications. This approach offers a safe and effective treatment option for complex renal stones, as the method exhibits a high clearance rate with few complications.

Comparison of novel flexible and traditional ureteral access sheath in retrograde intrarenal surgery.

OBJECTIVES: To compare the efficiency and safety of a novel flexible ureteral access sheath (f-UAS) and traditional ureteral access sheath (UAS) during retrograde intrarenal surgery (RIRS). PATIENTS AND METHODS: Between January 2022 and September 2022, a total of 152 consecutive cases with renal stones underwent RIRS with the f-UAS. Their outcomes were compared with those of another 152 consecutive cases undergoing RIRS with traditional UAS using a 1:1 scenario matched-pair analysis, with matching parameters including age and stone size. The f-UAS is a novel UAS with a 10-cm-long tube at the tip that can follow the bends of flexible ureteroscope (f-URS). RESULTS: Baseline characteristics were found to be similar between the two groups. The f-UAS group demonstrated significantly higher SFR (76.3% vs. 7.2%; P < 0.001) at 1 day postoperatively and a higher clearance rate of stone volume (98.11% vs. 91.78%; P < 0.001). The f-UAS group also had lower total complications rate (9.9% vs. 22.4%; P = 0.003), lower incidence of fever (5.9% vs 11.9%; P = 0.001), shorter operative times (56.5 min vs. 59.9 min; P = 0.047), and lower usage rate of baskets (17.1% vs. 100%; P < 0.001). There was no significant difference in SFR at 1 month postoperatively (P = 0.627) and in the length of postoperative hospital stay between the two groups (P = 0.225). CONCLUSION: Compared to the traditional UAS during RIRS, the f-UAS showed several advantages, including higher SFR at 1 day postoperatively, shorter operative times, lower incidence of complications, and less use of basket.

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.

Experimental and clinical applications and outcomes of using different forms of suction in retrograde intrarenal surgery. Results from a systematic review.

OBJECTIVE: To identify the latest advances in suction devices and evaluate their effect in Retrograde intrarenal surgery (RIRS) and ureteroscopy for stones. BASIC PROCEDURES: A systematic literature search was performed on 4th January 2023 using Scopus, PubMed, and EMBASE. Only English papers were included; both pediatric and adult studies were accepted. Duplicate studies, case reports, letters to the editor, and meeting abstracts were excluded. MAIN FINDINGS: Twenty-one papers were selected. Several methods have been proposed for suction use in RIRS, such as through the ureteral access sheath or directly to the scope. Artificial intelligence can also regulate this system, monitoring pressure and perfusion flow values. All the proposed techniques showed satisfactory perioperative results for operative time, stone-free rate (SFR), and residual fragments. Moreover, the reduction of intrarenal pressure (induced by aspiration) was also associated with a lower infection rate. Even the studies that considered kidney stones with a diameter of 20 mm or higher reported higher SFR and reduced postoperative complications. However, the lack of well-defined settings for suction pressure and fluid flow prevents the standardization of the procedure. CONCLUSION: Aspiration device in the surgical treatment of urinary stones favours a higher SFR, reducing infectious complications, as supported by the included studies. RIRS with a suction system provided to be a natural successor to the traditional technique, regulating intrarenal pressure and aspirating fine dust.