Stone-free Status Research Articles

In the Treatment of Lower Pole Kidney Stones Between 1-2 cm in Children, Which is the Best Approach? Retrograde Intrarenal Surgery or Mini Percutaneous Nephrolithotomy.

Kidney stones are treated with many methods, but there is no consensus on which method should be preferred for 1-2 cm lower renal stones. In our study, we aimed to investigate the results of mini (Percutaneous Nephrolithotomy) PCNL and (Retrograde Intrarenal Surgery) RIRS in lower renal pole 1-2 cm stones. Twenty-four mini PCNL and 55 RIRS patients were included in the study. Demographic data of the patients and information about stones on Non-Computed Tomography (NCCT) were recorded. Stone-free status (SFR), need for additional treatment and complications of both methods were compared. Operative time was 55.2±20.8 min in mini PCNL and 70.7±36.5 min in RIRS, which was statistically significantly lower (p=0.002). Length of hospital stay was 2.4±1.5 days in the mini PCNL and 1.3±0.7 days in the RIRS, which was statistically significantly longer (p=0.011). In the postoperative 1st month and 3rd month stone-free rates (SFR) were higher in the mini PCNL group. While the 1st month SFR was 91.6% and 54.5%, the 3rd month stone-free rates were 95.8% vs. 69.1%, respectively (p<0.001). The need for re-treatment was statistically lower in the mini PCNL group (p<0.001). In terms of complications, the incidence of complications was 16.6% (pain in 2 patients, fever in 1 patient, need for blood transfusion in 1 patient) in the mini PCNL group and 21.8% (pain in 2 patients, fever in 8 patients, sepsis in 2 patients) in the RIRS group. There was a significant difference between the two groups (p=0.008). Mini PCNL has a higher SFR, less need for re-treatment and fewer complications.

Comparison of stone clearance rate based on upper, middle, or lower calyx puncture in Mini Percutaneous Nephrolithotomy (mPCNL)

Introduction: PCNL is the most common surgical technique used for the management of renal stones, particularly for those with more than 2 cm stones. The aim of this study is to identify which kidney calyx—upper, middle, or lower—when punctured achieves the highest stone clearance rate. Methods: This was a prospective non-randomised study performed in department of urology, KIST medical college from September 1, 2021 to November 16, 2022. Patients who underwent PCNL were evaluated with detailed history, examination, and investigation. All the patients who fulfill the inclusion criteria during study period were included in the study. After preoperative investigation PCNL was done according to standard protocol. Perioperative complication recorded in Performa. Stone-free status was checked after 2 months of surgery with ultrasonography. Results: 100 patients were included in this study among which 59 were male. The mean age of patients was 33.35 years [range 18-65 years]. Upper, middle and lower pole puncture was done in 23%, 33% and 44% patients respectively. The mean stone burden of the patient was 380.680 mm2. The average time for surgery according to access was 67.34 mins, 63.12mins, and 64.07 mins for the upper calyx, mid-calyx and for the lower calyx respectively. 84.33% of patients had complete stone clearance after 2 months in the USG examination. 91.3% [21] had stone clearance when approached through the upper calyx. It was 87.8%[29] by mid calyx and 75%[33] by lower calyx. Upper calyx puncture had statistical significance in stone clearance rate [P=0.43, P=0.021, P=0.002]. 11 had CRIF ≤4mm stone in PCS, and the remaining 6 had residual stone &gt;4mm. In our study, thoracic complications were significantly higher in upper calyx puncture 8[30.4%, 8[24.24% in the middle calyx, and 3[6.8%] in lower calyx [P=0.02, P=0.98, P=0.03] respectively. Conclusion: Upper calyceal puncture can produce the highest stone clearance rate, but it has been associated with significant postoperative morbidity, particularly in the chest. Lower calyx punctures have less intraoperative and postoperative morbidity, but their stone removal rates are lower than those of other procedures. Therefore, the balance between stone clearance rate and morbidity has been achieved using middle calyx puncture.

Clinical Utility of S.T.O.N.E, Guy's Scoring System, and Renal Stone Complexity Scoring in Predicting Outcome of Single-Tract Percutaneous Nephrolithotomy.

Several imaging-basedscores have been developed to predict postoperative stone-free state (SFS) and complications. This study aimed to assess the accuracyof the S.T.O.N.E., Guy Scoring System (GSS), and Seoul National University Renal Stone Complexity (S-ReSCS) scores inpredicting theoutcomes of single-tract percutaneous nephrolithotomy (ST-PCNL). This scoring system holds paramount importance for low-incomeand low-middle-income countries (LMICs), as it is inexpensive and cost-effective for the healthcare system. This retrospective study was carried out with 147 participants. Based on the preoperative computerized tomographic (CT) scan, each patient's S.T.O.N.E. score, GSS, and S-ReSCS were recorded. The modified Clavien grading system was used to document intra- and postoperative complications. The mean age of the sample population was 45 years. SFS was achieved in 110 (74.8%) patients. The number of calyces involved (p = 0.008), S.T.O.N.E. scoring (p = 0.001), GSS (p = 0.008), and S-ReSCS (0.001) correlated well with the SFS. Forty-nine (33.33%) patients developed complications. The most common complications fell within Clavien grade II. No statistical significance was noted between the S.T.O.N.E. score, GSS, and S-ReSCS with the modified Clavien grading system. The S.T.O.N.E. scoring, GSS, and S-ReSCS have a high predictive value for achieving SFS in ST-PCNL. In addition, findings from LMICs are comparable with those from the rest of the world.

Influence of tract location on the outcomes of endoscopic combined intrarenal surgery: A retrospective analysis of 1000 cases.

This study aimed to investigate the influence of tract location on surgical outcomes in endoscopic combined intrarenal surgery (ECIRS), considering the location of residual stones. From January 2015 to December 2021, 1417 consecutive patients underwent ECIRS in three hospitals. After excluding patients with preoperative percutaneous nephrostomy, intended multi-stage procedures, those with a tract in the renal pelvis, and those with multiple tracts, 1000 patients were retrospectively analysed by comparing three groups based on tract location: group 1 (upper calyx), group 2 (middle calyx), and group 3 (lower calyx). A multivariate logistic regression model was implemented to assess whether the tract location independently affected the stone-free status. Patient characteristics were significantly different among the groups in terms of age, stone laterality, presence of calyceal stones, and hydronephrosis. There were no differences in stone-free rate (SFR) among the three groups. Multivariate analysis indicated that the tract location (group 1 or 2 compared with group 3) did not significantly affect the stone-free status (odds ratio = 1.4, 0.9-1.9, p = 0.066). Surgical duration significantly varied among the groups, with the shortest time observed in group 1. Organ injury was observed exclusively in group 1 (1.13%). Residual fragments were predominantly found in the lower calyx, with the calyx associated with the tract being the second most common location. Tract location does not significantly affect SFR. To improve the SFR, observation of the lower calyx and tract placement is important.

Prediction of percutaneous nephrolithotomy outcomes and flexible ureteroscopy outcomes using nephrolithometry scoring systems.

Kidney stones account for a high proportion of urological emergencies. The main objective of this paper is to evaluate the predictive ability of five scoring systems for overall stone-free status and postoperative complications after percutaneous nephrolithotomy and retrograde ureteroscopy. This study retrospectively analysed 312 cases of kidney stone patients between January 2021 and May 2022 at our centre. Multivariate logistic regression as well as ROC curves were applied to determine the ability to evaluate each scale to predict stone-free rates and postoperative complications. 179 patients have undergone PCNL. After multivariate logistic regression, the S.T.O.N.E score and history of ipsilateral renal surgery were predictive of stone-free status, and the predictive power of the S.T.O.N.E score was higher than that of history of ipsilateral renal surgery. Grade 1 complications were considered to be related to Guy's score and grade 2 complications were considered to be related to history of diabetes mellitus. 133 patients have undergone f-URS. After multivariate logistic regression analysis, the modified S-ReSC score, RUSS score, and R.I.R.S score were predictive of stone-free status, with the R.I.R.S score being the strongest predictor. Evidence of grade 2 complications was considered to be related to abnormal renal function. For PCNL, the S.T.O.N.E score had the best efficacy in predicting stone-free status, and the Guy's score had the best efficacy in predicting postoperative complications; for f-URS, the R.I.R.S score had the best efficacy in predicting stone-free status, and no scoring system predicted postoperative complications.

Super pulsed thulium fiber laser outcomes in retrograde intrarenal surgery for ureteral and renal stones: a systematic review and meta-analysis

BackgroundLaser lithotripsy using a thulium fiber laser (TFL) has become an effective treatment option for small renal stones with low complication rates. TFL has a higher absorption coefficient, smaller fibers, and better pulse rate capability.MethodsWe conducted a systematic review and meta-analysis to evaluate the published evidence regarding TFL's lithotripsy performance in retrograde intrarenal surgery (RIRS), for which we primarily assessed the outcomes of stone-free rate, operation time, and complications. We searched different databases from inception to April 2023. We assessed the methodological quality and risk of bias using the Cochrane Risk of Bias tool for randomized trials and the ROBINS-I tool for non-randomized studies. We used a random-effects model for meta-analysis and assessed heterogeneity using the I2 statistic.ResultsTwelve published studies evaluated the efficacy of RIRS using a TFL for treating renal and ureteral stones. The meta-analysis revealed a predicted stone-free rate of 89.37% (95% CI: 83.93% to 93.12%), indicating that, on average, approximately 89.37% of patients achieved a stone-free state after treatment. The substantial heterogeneity among the studies was evident, as shown by a Q-value of 33.1174 and a p-value of 0.0003. The I2 value of 69.80% (95% CI: 25.91% to 92.02%) highlighted the proportion of variability attributed to genuine heterogeneity across the studies. Moreover, the H2 value 3.31 (95% CI: 1.35 to 12.53) indicated significant heterogeneity beyond random chance. The estimated overall effect size (logit-transformed) of 2.1289 was highly statistically significant (z = 8.7648, p < 0.0001) with a confidence interval of 1.6528 to 2.6049. The reported complications varied across studies, encompassing Clavien grade I–II complications in most cases, with a subset experiencing more severe Clavien grade III–V complications. Additionally, other studies noted a range of complications, such as haematuria, fever, transient creatinine elevation, and postoperative issues like bleeding, pain, and sepsis.ConclusionThis meta-analysis suggests that RIRS using TFL is an effective and safe treatment option for renal and ureteral stones, with high stone-free and low complication rates. The included studies exhibited a low risk of bias and were of high quality. However, more extensive randomized controlled trials with extended follow-up periods are needed to investigate this technique's efficacy and safety.

Challenges of Retrograde Ureteroscopic Procedures in Overweight Patients.

Obesity and urolithiasis are both prevalent conditions that have an impact on the healthcare system. The ureteric diameter and accessibility play a crucial role in the management of urolithiasis in both overweight and normal weight patients. Studies have shown that obesity can lead to changes in ureter diameter where excessive body fat can exert pressure on the kidneys, causing them to enlarge in size and this enlargement can result in a compression of the adjacent structures, including the ureter. The aim of this study is to assess the incidence of intraoperative challenges faced during retrograde ureteroscopic procedures in overweight patients with ureteric and renal calculi. We retrospectively reviewed patients who underwent retrograde ureteroscopic surgery (RURS) for urolithiasis from 1st January 2021 until 30th August 2023. The outcome and any complications were documented and compared with the patient's Body Mass Index (BMI). All patients who undergo RURS in our facility have to have a Non-Contrast CT scan prior to surgery. Procedural success was determined by the ability to obtain access to the stone site intraoperatively and stone-free status in kidney, ureter, and bladder (KUB) X-ray post-operatively. Post-operative complications were recorded up to two weeks post-operatively and classified according to the Calvein Dindo Classification. Our total sample size was 146 patients out of which 75 were overweight and 71 were normal weight patients. In 34 (45%) of overweight patients' access to the ureter was restricted due to a narrow ureteric orifice with ureteroscopy not successful; on the contrary 13 (18%) of normal weight patients faced this same issue. This was statistically significant with a p-value of .004. The stone clearance rates were 91% and 95% in overweight and normal weight patients respectively, which is higher in normal weight patients however this difference was not found to be a statistically significant finding (p-value .028). Overweight patients had 12% Grade I and 8% Grade II complications whereas normal weight patients had 11% Grade I complications and 1.4% Grade II with no higher-grade complications. Retrograde ureteroscopic procedures are a safe treatment modality for patients with urolithiasis in both overweight and normal weight populations. They are shown to have similar success rates between both populations once ureteric access is obtained. However, access failure rates are shown to be slightly higher in overweight patients. Hence, further preoperative patient counselling and technical considerations should be undertaken.

Needle-Perc-Assisted Endoscopic Surgery in Treatment with Renal Staghorn Stones: A Prospective Randomized Controlled Study from a Large-Volume Stone Center

Introduction: The goal of this study was to evaluate the efficacy and safety of needle-perc-assisted endoscopic surgery (NAES) in the treatment of staghorn renal stones via a single-center prospective randomized controlled study. Methods: A total of 219 patients with partial or complete staghorn renal stones were prospectively randomized into two groups between January 2020 and April 2022. In group A (n = 112), patients were treated with traditional standard access, multiple if necessary, and in group B (n = 107), only one standard access was made, and needle-perc was assisted to remove the residual stones in the same stage. All procedures were guided under ultrasound totally. Stone size, operating time, blood loss, pain score, complications, and other related characteristics were monitored and analyzed. Results: Procedures were successful in all patients. The baseline characters were similar between the groups. The mean stone size was comparable (4.5 ± 1.4 vs. 4.7 ± 1.7, p = 0.35). The 1-month stone-free status was achieved in 85 patients (75.9%) in group A and 80 (74.8%) patients in group B (p = 0.72). The operation time was shorter in group A than B (75.1 ± 28.1 min vs. 97.2 ± 20.4 min, p = 0.02). A less blood loss (p = 0.01), shorter hospital stay (p = 0.04), lower pain score (p = 0.04), and lower severe complication rates (p = 0.03) were observed in group B. Conclusion: NAES reveals better postoperative recurrence compared with traditional multiple tracts method for treating staghorn renal stones. The stone-free rate was comparable between the two groups.

To Evaluate the Impact of Ho:YAG Laser Lithotripsy for Ureteroscopic Removal of Proximal and Distal Ureter Calculi.

Background Urinary calculus illness is a prevalent clinical issue encountered by the medical community, particularly urologists, in contemporary society. Laser technologies have been widely accepted as standard modalities for lithotripsy applications. Using the Ho:YAG laser has expanded the range of applications for ureteroscopic stone management (URS), enabling the treatment of bigger stones in all regions of the upper urinary tract. It is noteworthy that ureteroscopy (URS) demonstrates superior rates of stone clearance for distal stones, regardless of their size, with a success rate of 94.5% compared to 74% for other treatment modalities. Significant variation exists in the reported results and problems associated with Ho:YAG laser lithotripsy across different trials, as documented in the literature. The procedure's outcome might vary based on factors such as the size of the stone, the length of impaction, the presence of ureteral damage and granulation, the kind and size of endoscopes used, and the specific energy settings employed by various operators. The present study aimed to evaluate the impact of Ho:YAG laser lithotripsy for ureteroscopic removal of proximal and distal ureter calculi. Methods This prospective observational study was carried out in the Department of Urology at DY Patil Medical College and Hospital, Pune, from March 2021 to March 2023. Patients diagnosed with a case of ureteric stone who opted for URSL during the study period were included. A total of 50 patients who underwent URSL in the urology department were included in this study. These were then grouped into those with proximal ureteral stones and distal ureteral stones. (25 each) Results The study observed that patients diagnosed with proximal ureteral stones had bigger calculi, with a mean stone size of 15mm, in comparison to patients with distal ureteral stones, with a mean stone size of 10mm (P=0.010). The stone burden was significantly higher for proximal ureteral stone patients than those with distal ureteric stones (P=0.010). The average duration of the operating procedure for upper ureter stones was 70 minutes, but for lower stones, the mean operative time was 45 minutes (P<0.001). No statistical significance was seen in the median age of patients between the two groups (P=0.89). The maximum number of cases in the upper stone group were in the age group of 16-30 years, and in the lower stone group was in the age group of 31-45 years. The prevalence of DJ stents at the time of presentation was higher among patients diagnosed with proximal ureteric stones than those with distal ureteric stones, with rates of 28% and 20%, respectively (P=0.508). Full fragmentation was successfully accomplished in all patients within the distal calculus group, accounting for 100% of the cases. At the same time, for proximal ureteric stones, a single laser lithotripsy session resulted in 92% (23 patients) achieving a stone-free status after two weeks. Conclusion The study observed that stone size, burden, and procedure duration were statistically significant among other criteria. Mean age, stone HU, prior DJ stent, and stone-free rate were statistically insignificant. The procedure indicated that Ho:YAG laser lithotripsy has efficacy in treating both proximal and distal ureteral stones, with minimal intraoperative and postoperative complications. None of the complications were due to laser energy.

COMPARISON OF RETROGRADE INTRARENAL SURGERY OUTCOME VERSUS PERCUTANEOUS NEPHROLITHOTOMY IN RENAL STONES &gt;2 CM IN DIAMETER IN LOWER CALYCES AT A TERTIARY CARE HOSPITAL

This study aimed to compare the outcome of Retrograde Intrarenal Surgery and Percutaneous Nephrolithotomy in treating renal stones larger than 2 cm in diameter in lower calyces at a tertiary care hospital. A randomized control trial was conducted at the Department of Urology, Bahawal Victoria Hospital, Bahawalpur, for 8 months from 01-06-2021 to 01-02-2022 using a non-probability purposive sampling technique. Seventy patients met the inclusion and exclusion criteria and were enrolled in the study. The patients were randomly divided into two groups using a lottery method. Group A underwent PCNL, while Group B underwent RIRS. During the procedure, the operative time was noted from the time of intubation to the time of extubation. After the procedure, the duration of hospital stay was noted, and the patients were followed up in the OPD for 12 weeks. After 12 weeks, an abdominal ultrasound was conducted to evaluate if there were any residual stones. If there were no residual stones, the patients were labeled stone-free. Seventy patients participated in the study, with a mean age of 45.51±13.68 years, ranging from 20 to 69 years. The mean age of patients in the RIRS group was 47.63 ± 13.51 years, while in the PCNL group, it was 43.40 ± 13.71 years, with a non-significant p-value of 0.198. The gender distribution among the patients revealed that 30 (42.86%) were male and 40 (57.14%) were female, with an equal distribution of males (15, 42.9%) in both the RIRS and PCNL groups. However, there were substantial differences in the duration of surgery, with the RIRS group having a mean operative time of 107.57 ± 6.99 minutes and the PCNL group having a significantly shorter mean operative time of 75.86 ± 7.19 minutes (p-value &lt; 0.001). Moreover, the RIRS group had a shorter mean hospital stay, with 4.77 ± 1.03 days compared to 5.46 ± 1.09 days in the PCNL group (p-value = 0.009). Post-procedure, 63 (90%) patients achieved stone-free status, with 29 (82.9%) patients in the RIRS group and 34 (97.1%) in the PCNL group, with a non-significant p-value of 0.106. This study concluded that RIRS is a safe procedure and a good alternative to PCNL in treating renal stones larger than 2 cm in diameter in lower calyces to achieve stone-free status and length of hospital stay.

Comparison of endoscopic versus CT assessment of stone-free status after percutaneous nephrolithotomy (PCNL)

This study is aimed to determine whether postoperative low dose computed tomography (LDCT) imaging is necessary after percutaneous nephrolithotomy (PCNL), or the surgeon's intraoperative assessment of residual fragments (RF) is sufficient and avoidance of postoperative imaging with reduction of radiation exposure can be achieved. Data of all 610 patients who underwent PCNL in prone position in our institution from February 2009 to September 2020 was collected. Parameters such as age, gender, BMI, ASA-Classification, stone related parameters and the surgeon’s assessment of stone-free status were analyzed. The LDCT performed postoperatively was compared to the intraoperative assessment of the surgeon regarding RF. The mean age of patients was 52.82 years; the mean BMI was 28.18 kg/m2. In 418 cases, the surgeon made a clear statement about the presence of RF and postoperative LDCT was carried out. The discrepancy between the two methods (surgeon´s assessment vs. LDCT) was significant at p < 0.0001. The sensitivity, specificity, positive and negative predictive value of the surgeon when assessing RF were 24.05%, 99.45%, 98.28% and 50%. Stone free rate (SFR) after primary PCNL was 45.57%. The overall SFR at discharge was 96.23%. Although the surgeon´s assessment of RF was reliable, postoperative LDCT imaging should still be performed if endoscopic stone clearance is suspected due to the high false negative rate and the low negative predictive value. The optimal timing of postoperative imaging following PCNL remains unclear.

Flexible ureteroscopy under local anesthesia for stone management: initial exploration and two-year experience

ABSTRACT Background Flexible ureteroscopy (f-URS) is a minimally invasive surgical technique used for treating urinary tract stones. While general anesthesia (GA) is the standard method used, it comes with risks. Local anesthesia (LA) is a safer and more cost-effective alternative to GA, and its use in f-URS could potentially reduce patients’ risks and increase accessibility to treatment. This study aims to investigate the feasibility, safety, and efficacy of using LA for f-URS in treating stones, as an initial experience in the diagnosis related group (DRG) era of China. Methods Patients who met the inclusion and exclusion criteria and were continuously included in the study Between 2021 and 2023. We analyzed the stone free status, postoperative complication rate, hospitalization costs, and presented key points of the procedure performed under LA that we had summarized over the past two years. Results A study of 614 patients undergoing f-URS under LA for urinary stones in our hospital showed 83.4% stone-free rate with a mean operative time of 44.12 ± 16.63 minutes; 18 patients experienced fever postoperatively, and 12 had ureteral injuries. No severe complication was reported. The cost of LA was found to be only 1.7% of the DRG payment, which is around $40. The highest VAS scores were observed during the sheath insertion, with STAI scores decreasing during and after surgery. Conclusions The study revealed that f-URS administered under LA was a well-tolerated, efficient, safe, and economical procedure. In the DRG era, this new anesthetic option for f-URS provides urologists with a more cost-effective alternative.

Success of Extracorporeal Shockwave Lithotripsy (ESWL) in Relation to Triple D Score

Aim: To determine the frequency of success of ESWL in patients with renal stones and to compare the success of ESWL with different Triple D scores in the same group of patients. Methodology: Descriptive study in the Department of Urology, Sindh Institute of Urology and Transplantation Hospital, Karachi from 29thOctober 2020 to 28th April 2020. One hundred and fifteen patients with renal stone seen as radio opaque shadow on X rays KUB were included. CT was performed and stone diameters were measured. Quadruple D-score was defied because stone location is combined with TrD-S ranging from 0 (worst) to 3 (best) points. KUB was used for evaluation of stone free status after 4-weeks of ESWL sessions. Patient can be regarded stone free if complete stone was removed. Results: The mean age was 48.99±10.67 years, the mean size of the stone was 12.99±3.54mm, and the mean triple D score was 1.70±1.00. There were 75(65.22%) males and 40(34.78%) female patients. The success of ESWL was found in 79(68.70%) patients. On comparison of success of ESWL with triple D score, success of ESWL was found in 04(26.7%) having 0 score, in 19(54.3%) having 01 score, in 27(77.1%) having 02 score, and in 29 (96.7%) having 03 score (P&lt;0.001). Conclusion: The triple D score appears to be a useful predictor of ESWL treatment outcomes. Using the Triple D score may improve the cost-effectiveness of ESWL by limiting its use to patients likely to have favourable outcomes. Key Words: Extracorporeal shockwave lithotripsy (ESWL), Triple D score, Renal stone

Current role of endoscopic combined intrarenal surgery in the management of renal stones: A scoping review

ABSTRACT Introduction: This study aims to review the current role of endoscopic combined intrarenal surgery (ECIRS) in the management of renal stones, with a focus on its efficacy and safety. The secondary outcome was to highlight the tips and tricks to improve the urologist’s experience with ECIRS. Methods: A scoping review of the literature, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines, was performed, using ECIRS and flexible ureteroscopy and percutaneous nephrolithotomy as the search terms. All original articles were screened and included. Results: Thirty-three studies were included in the analysis. ECIRS showed a good efficacy and safety profile, with an excellent stone-free rate and a low rate of complications, mostly Clavien–Dindo I/II. With ECIRS, a reduction in the need for multiple access tracts was noted and direct visualization of the targeted calyx during the puncture increased the ability to attain transpapillary punctures, thereby reducing the amount of bleeding. Conclusion: ECIRS, as the first-line minimal access intervention, is safe and efficacious, particularly for achieving a stone-free status in patients with large complex stones in a single stage. The ability to gain access under direct vision and the reduction in the number of tracts, in both the supine and the prone positions, makes this procedure an attractive surgical choice.

Comparison between different radiological scoring systems in predicting post-PCNL outcome

Background: Various scoring systems, including Guy's stone score (GSS), S.T.O.N.E. score, and Clinical Research Office of the Endourological Society (CROES) nomogram, have been assessed for predicting post-percutaneous nephrolithotomy (PCNL) success in terms of stone-free status (SFS) and complications. Our study aims to determine the optimal predictor of SFS among these systems and assess their efficacy in predicting perioperative factors and complications, using modified Clavien grade. Methods: This prospective hospital-based cohort study involved 107 patients aged ≥18 years who underwent standard PCNL (tract size &gt;24 Fr) within a year. GSS, S.T.O.N.E. score, and CROES nomogram were calculated using preoperative computed tomography (CT) scans. Comparisons between 'stone-free' and 'residual-stone' groups were statistically analyzed. Results: All parameters effectively predicted SFS. S.T.O.N.E. score exhibited excellent discriminatory power (AUC 0.844; 95% CI: 0.762-0.907), followed by GSS (AUC 0.756; 95% CI: 0.663-0.834) and CROES nomogram (AUC 0.749; 95% CI: 0.656-0.828). S.T.O.N.E. score, with an AUC of 0.844, proved the most accurate predictor at ≤7 cut-off. GUY's score correlated positively with operative time and hospital stay (correlation coefficient 0.403, 0.34). S.T.O.N.E. score also positively correlated with these factors (correlation coefficient 0.443, 0.37). CROES nomogram negatively correlated with operative time and hospital stay (correlation coefficient -0.374, -0.314). Conclusions: All scoring systems effectively predict post-PCNL SFS, with S.T.O.N.E. score being the most predictive. GSS and S.T.O.N.E. score associate significantly with operative time and hospital stay. Both GSS and S.T.O.N.E. score show significant associations with perioperative complications assessed by modified Clavien grade.

The Role of Scoring Systems in Predicting Surgical Success in Percutaneous Nephrolithotomy: Results from a Single Center

Objective: In this study, we aimed to determine the effectiveness of Guy’s score, S.T.O.N.E score, and CROES nomogram, the most widely used models in percutaneous nephrolithotomy (PNL) for predicting stone-free status, and to determine which model predicts stone-free status more successfully. Materials and Methods: The data of patients older than 18 years of age who underwent PNL for kidney stones at our tertiary academic center between 2009 and 2018 were retrospectively analyzed. Examined parameters included the demographic data of patients, stone characteristics, Guy’s score, S.T.O.N.E. score, CROES nomogram, surgical duration, transfusion rate, length of stay, and stone-free status. Prediction values for stone-free status were determined using receiver operating characteristic (ROC) curve analysis. Results: A total of 200 patients were included in the study. The mean age of the patients was 43.7 ± 14.6 years. The mean stone scores of the patients were as follows: Guy’s score: 2.11 ± 1.01; S.T.O.N.E. score: 7.54 ± 1.73; and CROES nomogram: 194 ± 62.7. The stone-free rate was determined to be 66%. The Guy’s and S.T.O.N.E. scores were significantly higher, and the CROES nomogram was significantly lower in non-stonefree patients compared to stone-free patients (p&amp;lt;0.001, p&amp;lt;0.001, and p&amp;lt;0.001, respectively). The cut-off value and area under curve (AUC) were 2.5 and 0.770 for Guy’s score, 7.5 and 0.722 for S.T.O.N.E score, and 185 and 0.843 for CROES nomogram, respectively. Conclusion: Guy’s score, S.T.O.N.E score, and CROES nomogram are effective models in predicting stonefree status in PNL.

Ultrasound-guided percutaneous nephrolithotomy (PCNL) success rates in patients with elevated body mass index: a comparative study.

Percutaneous nephrolithotomy (PCNL) is considered gold standard treatment of renal stones larger than 20mm. Several studies have shown that ultrasound guidance during this procedure is more effective and safer than fluoroscopy. A higher body mass index (BMI) can make ultrasound-guided renal access more difficult and unsuccessful. We present a prospective analysis and comparison of ultrasound-guided PCNL in patients with normal and increased body mass index. We performed a prospective comparison of patients who underwent ultrasound-guided PCNL to remove renal stones by a single surgeon between 2020 and 2022. Patients with BMIs greater than 30 (mean 33.87-obese) were compared to those with BMIs less than 30 (mean 25.69-non-obese). Demographic, perioperative, and follow-up data were collected, analyzed, and included in this study. Total of 98 consecutive patients, with 49 patients in each group were analyzed. No statistically significant differences were observed in terms of stone volume (P = 0.085), stone density (P = 0.5590), location of renal access (P = 0.108), surgery duration (P = 0.38), blood loss (P = 0.54), or laboratory changes after surgery (P = 0.60). 87.76% of obese patients were stone free per CT scan at follow-up, compared to 73.47% of normal-weight patients (P = 0.1238). According to Clavien-Dindo classification, six patients in the non-obese group experienced grade II (10%) and grade III (2%) complications, as opposed to six patients in the obese group with grade I (2%), grade II (6%), and grade III (2%) complications. There was no significant correlation between body mass index and the success or safety of ultrasound-guided PCNL. Although more challenging, a higher BMI should not be an impediment to performing this approach. This method is safe, with no increased incidence of postoperative complications or compromise in stone-free status postoperatively and can diminish or avoid both patient's and medical team's exposure to ionizing radiation.

The outcomes of flexible ureteroscopy for renal calculi of 2 cm or more with and without the use of ureteral access sheath: A retrospective study.

The rate of success of retrograde intrarenal surgery (RIRS) for treating urinary tract stones is high, and the procedure is growing in popularity. The routine use of ureteral access sheath (UAS) remains somewhat controversial. The aim of this study was to assess the efficacy and safety of employing UAS during flexible ureteroscopy for treating renal stones ≥ 2 cm. This retrospective study was accomplished from January 2021 to February 2023. From 495 consecutives flexible ureteroscopies, 112 patients had renal stones ≥ 2 cm (60 patients with the use of UAS and 52 patients without). The stone-free status was verified after 8 weeks of operation. The average diameter of the renal stones in non-UAS or UAS treated groups was 22.5 mm and 22.6, respectively. None of the groups differed significantly in terms of stone side, stone size, stone position, or Hounsfield unite but there was significant difference (p < 0.001) among two groups as regard pre-operative stenting (cases with UAS had 23.3% pre-operative stenting). It is not always necessary to use UAS in conjunction with flexible ureteroscopy and laser lithotripsy to treat renal calculi bigger than or equal two cm. Without the assistance of UAS, the surgery may be carried out successfully and safely.

Predicting the Stone-Free Status of Percutaneous Nephrolithotomy with the Machine Learning System.

The study aimed to create a machine learning model (MLM) to predict the stone-free status (SFS) of patients undergoing percutaneous nephrolithotomy (PCNL) and compare its performance to the S.T.O.N.E. and Guy's stone scores. This is a retrospective study that included 320 PCNL patients. Pre-operative and post-operative variables were extracted and entered into three MLMs: RFC, SVM, and XGBoost. The methods used to assess the performance of each were mean bootstrap estimate, 10-fold cross-validation, classification report, and AUC. Each model was externally validated and evaluated by mean bootstrap estimate with CI, classification report, and AUC. Out of the 320 patients who underwent PCNL, the SFS was found to be 69.4%. The RFC mean bootstrap estimate was 0.75 and 95% CI: [0.65-0.85], 10-fold cross-validation of 0.744, an accuracy of 0.74, and AUC of 0.761. The XGBoost results were 0.74 [0.63-0.85], 0.759, 0.72, and 0.769, respectively. The SVM results were 0.70 [0.60-0.79], 0.725, 0.74, and 0.751, respectively. The AUC of Guy's stone score and the S.T.O.N.E. score were 0.666 and 0.71, respectively. The RFC external validation set had a mean bootstrap estimate of 0.87 and 95% CI: [0.81-0.92], an accuracy of 0.70, and an AUC of 0.795, While the XGBoost results were 0.84 [0.78-0.91], 0.74, and 0.84, respectively. The SVM results were 0.86 [0.80-0.91], 0.79, and 0.858, respectively. MLMs can be used with high accuracy in predicting SFS for patients undergoing PCNL. MLMs we utilized predicted the SFS with AUCs superior to those of GSS and S.T.O.N.E scores.

Outcomes of (chinese) mini-percutaneous nephrolithotomy for renal stones: a prospective trial

Objective: Mini-percutaneous nephrolithotomy (mini-PCNL) has been recently advocated as a minimally invasive procedure for the management of renal stone. In this trial, we assessed the postoperative outcomes of chinese mini-PCNL (MPCNL) in adult patients with renal calculi less than 3 cm in diameter. Material and methods: We performed a single-arm prospective trial that recruited adult patients with unilateral single kidney stones less than 3 cm. Patients were followed up for the assessment of postoperative complications and stone-free status. Results: Sixty patients were included in the present study, with a mean age of 36.9 ±8.5 years and slightly male predominance (56.7%). The mean operative time was 133.7 ±29.2 minutes. None of the patients needed a nephrostomy tube or DJ tube stent. The mean hospital stay was 1.4±0.62 days. Eight patients (13.3%) showed mild perinepheric collection on the postoperative US. All patients had mild postoperative pain, with no incidence of post-operative bleeding, residual stone, sepsis, or pelvi-calyceal injury. A total of four patients (6.7%) had a postoperative fever. The incidence of postoperative urine was 13.3%. Conclusion: Chinese Mini-PCNL is an effective minimally invasive modality for the management of renal calculi less than 3 cm, with a low rate of postoperative complications and excellent stone-free status. Mini-PCNL can be used in well-resourced centres to reduce postoperative complications and hospital stay among patients with renal calculi.