Ureteroscopy vs laparoscopic ureterolithotomy for large proximal ureteric stone: a randomised trial.

OBJECTIVE: To compare the outcomes of retrograde flexible ureteroscopy (fURS) with retroperitoneal laparoscopic ureterolithotomy (RLU) for large proximal ureteric stones. PATIENTS AND METHODS: A prospective randomised trial was conducted from January 2018 through December 2022 including patients with impacted proximal ureteric stones of 15-25 mm. Patients underwent fURS or RLU. Primary outcome was the stone-free rate. Demographic data, stone features, and complications rates were also compared between groups. RESULTS: A total of 64 patients were enrolled, 32 in each group. The mean impacted stone time was similar between groups, as well as stone size (17 mm) and stone density (>1000 Hounsfield Units). The ureteric stone-free rates between the two groups (93.7% in fURS vs 96.8% in RLU; odds ratio [OR] 0.72, 95% confidence interval [CI] -1.72 to 3.17; P = 0.554), and overall success rates, which take into account residual fragments in the kidney (84.3% in fURS vs 93.7% in RLU; OR 1.02, 95% CI -0.69 to 2.74; P = 0.23), were similar. Operative time was also not statistically significantly different between groups (median 80 vs 82 min; P = 0.101). There was no difference in hospital length of stay. Retropulsion rate was higher with fURS (65.6% vs 3.1%; p < 0.001). Residual hydronephrosis (34.3% each group) and complication rates did no differ according to treatment. CONCLUSION: Flexible URS and RLU are both highly efficient and present low morbidity for large impacted proximal ureteric stone treatment. RLU is not superior to fURS.

Intraoperative computed tomography for detection of residual stones in endourology procedures: systematic review and meta-analysis.

BACKGROUND: Success rates in endourological procedures, notably percutaneous nephrolithotomy (PCNL) and ureteroscopy (URS), have demonstrated suboptimal outcomes, leading to more reinterventions and radiation exposure. Recently, the use of intraoperative computed tomography (ICT) scans has been hypothesized as a promising solution for improving outcomes in endourology procedures. With this considered, we conducted a comprehensive systematic review and meta-analysis encompassing all available studies that evaluate the impact of the use of intraoperative CT scans on surgical outcomes compared to conventional fluoroscopic-guided procedures. METHODS: This systematic review was conducted in accordance with PRISMA guidelines. Multiple databases were systematically searched up to December of 2023. This study aimed to directly compare the use of an ICT scan with the standard non-ICT-guided procedure. The primary endpoint of interest was success rate, and the secondary endpoints were complications and reintervention rates, while radiation exposure was also evaluated. Data extraction and quality assessment were performed following Cochrane recommendations. Data was presented as an Odds ratio with 95%CI across trials and a random-effects model was selected for pooling of data. RESULTS: A comprehensive search yielded 533 studies, resulting in the selection of 3 cohorts including 327 patients (103 ICT vs 224 in non-ICT). Primary outcome was significantly higher in the experimental group versus the control group (84.5% vs 41.4% respectively, 307 patients; 95% CI [3.61, 12.72]; p<0.00001; I2=0). Reintervention rates also decreased from 32.6% in the control to 12.6% in the ICT group (OR 0.34; 95%CI [0.12,0.94]; p =0.04; I2= 48%), whereas complication rates did not exhibit significant differences. Radiation exposure was also significantly reduced in two of the included studies. CONCLUSION: This meta-analysis highlights a favorable outcome with intraoperative CT scan use in PCNL procedures, showing a considerable increase in SFR when compared to standard fluoroscopy and nephroscopy. Despite limited studies, our synthesis underscores the potential of ICT scans to significantly reduce residual stones and their consequences for endourology patients, as reinterventions and follow-up ionizing radiation studies.

Endoscopic Combined Intrarenal Surgery: best practices and future perspectives.

INTRODUCTION: Endoscopic Combined Intrarenal Surgery (ECIRS) has emerged as a promising technique for the management of large and complex kidney stones, potentially offering advantages over traditional Percutaneous Nephrolithotomy (PCNL). This study aims to evaluate best practices, outcomes, and future perspectives associated with ECIRS. MATERIALS AND METHODS: A comprehensive PubMed search was conducted from 2008 to 2024, using MESH terms and the following key words: "ECIRS" and "Endoscopic Combined Intrarenal Surgery" The search yielded 157 articles, including retrospective cohort studies, two randomized controlled trials (RCTs), and four meta-analyses comparing ECIRS with PCNL. Most important findings were summarized regarding indications, patient positioning, kidney access, tract size, surgical outcomes, and complications. RESULTS: ECIRS demonstrated higher stone-free rate, lower complication rate, and a reduced need for multiple procedures compared to traditional PCNL. Additionally, ECIRS has the potential to integrate new technologies to further enhance outcomes. CONCLUSION: ECIRS demonstrates significant advantages in the management of large kidney stones. Future research should focus on well-designed RCTs to provide robust evidence of its efficacy, safety, and cost-effectiveness, potentially establishing ECIRS as the first option treatment for complex kidney stones.

Supine versus Prone Percutaneous Nephrolithotomy for Complex Stones: A Multicenter Randomized Controlled Trial.

PURPOSE: High-quality evidence comparing supine to prone percutaneous nephrolithotomy (PCNL) for the treatment of complex stones is lacking. This study aimed to compare the outcomes of supine position (SUP) and prone position (PRO) PCNL. MATERIALS AND METHODS: A noninferior randomized controlled trial was performed according to the CONSORT (Consolidated Standards for Reporting Trials) criteria. The inclusion criteria were patients over 18 years of age with complex stones. SUP was performed in the Barts flank-free modified position. Except for positioning, all the surgical parameters were identical. The primary outcome was the difference in the success rate on the first postoperative day (POD1) between groups. The secondary outcome was the difference in the stone-free rate (SFR) on the 90th postoperative day (final SFR). A noninferiority margin of 15% was used. Demographic, operative, and safety variables were compared between the groups. Statistical significance was set at p <0.05. RESULTS: Overall, 112 patients were randomized and their demographic characteristics were comparable. The success rates on POD1 were similar (SUP: 62.5% vs PRO: 57.1%, p=0.563). The difference observed (-5.4%) was lower than the predefined limit. The final SFRs were also similar (SUP: 55.4% vs PRO: 50.0%, p=0.571). SUP had a shorter operative time (mean±SD 117.9±39.1 minutes vs 147.6±38.8 minutes, p <0.001) and PRO had a higher rate of Clavien ≥3 complications (14.3% vs 3.6%, p=0.045). CONCLUSIONS: Positioning during PCNL for complex kidney stones did not impact the success rates; consequently, both positions may be suitable. However, SUP might be associated with a lower high-grade complication rate.

Tranexamic acid in patients with complex stones undergoing percutaneous nephrolithotomy: a randomised, double-blinded, placebo-controlled trial.

OBJECTIVES: To assess the efficacy and safety of single-dose tranexamic acid on the blood transfusion rate and outcomes of patients with complex kidney stones undergoing percutaneous nephrolithotomy (PCNL). PATIENTS AND METHODS: In a randomised, double-blinded, placebo-controlled trial, 192 patients with complex kidney stone (Guy's Stone Scores III-IV) were prospectively enrolled and randomised (1:1 ratio) to receive either one dose of tranexamic acid (1 g) or a placebo at the time of anaesthetic induction for PCNL. The primary outcome measure was the occurrence rate of perioperative blood transfusion. The secondary outcome measures included blood loss, operative time, stone-free rate (SFR), and complications. ClinicalTrials.gov identifier: NCT02966236. RESULTS: The overall risk of receiving a blood transfusion was reduced in the tranexamic acid group (2.2% vs 10.4%; relative risk, 0.21, 95% confidence interval [CI] 0.03-0.76, P = 0.033; number-needed-to-treat: 12). Patients randomised to the tranexamic acid group had a higher immediate and 3-month SFR compared with those in the placebo group (29% vs 14.7%, odds ratio [OR] 2.37, 95% CI 1.15-4.87, P = 0.019, and 46.2% vs 28.1%, OR 2.20, 95% CI 1.20-4.02, P = 0.011, respectively). Faster haemoglobin recovery occurred in patients in the tranexamic acid group (mean, 21.3 days; P = 0.001). No statistical differences were found in operative time and complications between groups. CONCLUSIONS: Tranexamic acid administration is safe and reduces the need for blood transfusion by five-times in patients with complex kidney stones undergoing PCNL. Moreover, tranexamic acid may contribute to better stone clearance rate and faster haemoglobin recovery without increasing complications. A single dose of tranexamic acid at the time of anaesthetic induction could be considered standard clinical practice for patients with complex kidney stones undergoing PCNL.

Percutaneous nephrolithotomy in patients with spinal cord injury: should all these patients be automatically assigned a Guy's stone score of 4?

PURPOSE: To assess the complication and stone-free rates of PCNL in patients with spinal cord injury (SCI) and to evaluate whether this population should be assigned a Guy's stone score (GSS) of 4. METHODS: A case-control study was conducted, and electronic charts were reviewed to search for patients with SCI, bladder dysfunction, and kidney stones who had undergone PCNL. Control cases were randomly selected from among patients with complete staghorn calculus (GSS = 4). RESULTS: One hundred and seventeen patients were included. Patients with SCI had a significant shorter operative time (119 vs. 141 min; p = 0.018). There were no significant differences between the groups in terms of the patients' position, number of renal tracts, bleeding or transfusion rate; however, there was a significantly higher complication rate (23.1% vs. 7.8%; p = 0.009) and a longer hospital stay (5.8 vs. 3.1 days; p = 0.002) among patients with SCI. With regards to the stone-free rate in patients with different grades of GSS patients with SCI who had a GSS of 1 had a stone-free rate of 85.7%, while those with a GSS of 2, 3, or 4 had 50%, 50%, and 31.5%, respectively (p = 0.024). Only patients with a GSS of 4 in the SCI group had outcomes that were similar to those of control patients (31.5% vs. 31.6%). CONCLUSION: Patients with SCI should not be automatically assigned GSS 4. Stone-free rate is related to stone burden in these patients, although they do show a higher complication rate and a longer hospital stay than non-neurological patients.

The impact of COVID-19 in medical practice. A review focused on Urology.

COVID-19 pandemic is a rapidly spreading virus that is changing the World and the way doctors are practicing medicine. The huge number of patients searching for medical care and needing intensive care beds led the health care system to a burnout status especially in places where the care system was already overloaded. In this setting, and also due to the absence of a specific treatment for the disease, health authorities had to opt for recommending or imposing social distancing to relieve the health system and reduce deaths. All other medical specialties non-directly related to the treatment of COVID-19 had to interrupt or strongly reduce their activities in order to give room to seriously ill patients, since no one knows so far the real extent of the virus damage on human body and the consequences of doing non deferrable procedures in this pandemic era. Despite not been a urological disease, the urologist needs to be updated on how to deal with these patients and how to take care of himself and of the medical team he works with. The aim of this article is to review briefly some practical aspects of COVID-19 and its implications in the urological practice in our country.

Staghorn renal stones: what the urologist needs to know.

Patients with staghorn renal stones are challenging cases, requiring careful preoperative evaluation and close follow-up to avoid stone recurrence. In this article we aim to discuss the main topics related to staghorn renal stones with focus on surgical approach. Most of staghorn renal stones are composed of struvite (magnesium ammonium phosphate) and are linked to urinary tract infection by urease-producing pathogens. Preoperative computed tomography scan and careful evaluation of all urine cultures made prior surgery are essential for a well-planning surgical approach and a right antibiotics choice. Gold standard surgical technique is the percutaneous nephrolithotomy (PCNL). In cases of impossible percutaneous renal access, anatrophic nephrolithotomy is an alternative. Shockwave lithotripsy and flexible ureteroscopy are useful tools to treat residual fragments that can be left after treatment of complete staghorn renal stone. PCNL can be performed in supine or prone position according to surgeon's experience. Tranexamic acid can be used to avoid bleeding. To check postoperative stone-free status, computed tomography is the most accurate imaging exam, but ultrasound combined to KUB is an option. Intra-operative high-resolution fluoroscopy and flexible nephroscopy have been described as an alternative for looking at residual fragments and save radiation exposure. The main goals of treatment are stone-free status, infection eradication, and recurrence prevention. Long-term or short-term antibiotic therapy is recommended and regular control imaging exams and urine culture should be done.

Renal manifestations of sarcoidosis: from accurate diagnosis to specific treatment.

Sarcoidosis is a multisystem granulomatous disease characterized by epithelioid noncaseating granulomas associated with clinical and radiologic findings. The cause of this disease is still uncertain. Sarcoidosis affects mostly lungs and lymph nodes and is not usually considered a urological disease, therefore, this etiology may be overlooked in several urological disorders, such as hypercalcemia, hypercalciuria and nephrolithiasis. It affects all races and genders. This review aims to describe the urological manifestations of sarcoidosis and to elucidate how the disease may affect the management of numerous urological conditions.

Polymorphism in the PBX1 gene is related to cystinuria in Brazilian families.

The aim of our study was to determine regions of loss of heterozygosity, copy number variation analysis, and single nucleotide polymorphisms (SNPs) in Brazilian patients with cystinuria. A linkage study was performed using DNA samples from six patients with cystinuria and six healthy individuals. Genotyping was done with the Genome-Wide Human SNP 6.0 arrays (Affymetrix, Inc., Santa Clara, CA, USA). For validation, SNPs were genotyped using a TaqMan® SNP Genotyping Assay Kit. The homozygote polymorphic genotype of SNP rs17383719 in the gene PBX1 was more frequent (P = 0.015) in cystinuric patients. The presence of the polymorphic allele for this SNP increased the chance of cystinuria by 3.0-fold (P = 0.036). Pre-B-cell leukaemia transcription factor 1 (PBX1) was overexpressed 3.3-fold in patients with cystinuria. However, when we compared the gene expression findings with the genotyping, patients with a polymorphic homozygote genotype had underexpression of PBX1, while patients with a heterozygote or wild-type homozygote genotype had overexpression of PBX1. There is a 3-fold increase in the risk of the development of cystinuria among individuals with this particular SNP in the PBX1 gene. We postulate that the presence of this SNP alters the expression of PBX1, thus affecting the renal absorption of cystine and other amino acids, predisposing to nephrolithiasis.

Robot - assisted laparoscopic local recurrence resection after radical prostatectomy.

INTRODUCTION AND OBJECTIVE: Local prostate cancer recurrence is usually treated with salvage radiation (sRDT) with or without adjuvant therapy. However, surgical resection could be an option. We aim to present the surgical technique for robot - assisted laparoscopic resection prostate cancer local recurrence after radical prostatectomy (RP) and sRDT in 2 cases. PATIENTS AND METHOD: First case depicts a 70 year - old man who underwent RP in 2001 and sRDT in 2004. Following adjuvant therapy, patient had biochemical recurrence. MRI showed a solid mass in the prostatic fossa close to vesicourethral anastomosis, measuring 2.1 cm and PET / CT revealed hyper caption significant uptake in the prostatic fossa. Second case is a 59 year - old man who underwent RP in 2010 and sRDT in 2011. Again, patient presented with biochemical recurrence. PET / CT showed hyper caption in the prostatic fossa. Biopsy conformed a prostate adenocarcinoma. Both patients underwent robot - assisted extended pelvic lymph nodes dissection and local recurrence resection. A standard 4 robotic arms port placement was utilized. RESULTS: Both procedures were uneventfully performed in less than 3 hours and there were no complications. Pathological examination showed a prostate adenocarcinoma Gleason 7 and 8 in the first and second case, respectively; surgical margins and lymph nodes were negative. After 6 months of follow-up, continence was not affected and both patients presented with PSA < 0.15 ng / mL. CONCLUSION: Robot - assisted laparoscopic resection of prostate cancer local recurrence after RP and sRDT detected by PSMA PET / CT seems to be safe in experienced hands. It may postpone adjuvant therapy in selected cases.

A comprehensive literature-based equation to compare cost-effectiveness of a flexible ureteroscopy program with single-use versus reusable devices.

PURPOSE: To critically review all literature concerning the cost-effectiveness of flexible ureteroscopy comparing single-use with reusable scopes. MATERIALS AND METHODS: A systematic online literature review was performed in PubMed, Embase and Google Scholar databases. All factors potentially affecting surgical costs or clinical outcomes were considered. Prospective assessments, case control and case series studies were included. RESULTS: 741 studies were found. Of those, 18 were duplicated and 77 were not related to urology procedures. Of the remaining 646 studies, 59 were considered of relevance and selected for further analysis. Stone free and complication rates were similar between single-use and reusable scopes. Operative time was in average 20% shorter with digital scopes, single-use or not. Reusable digital scopes seem to last longer than optic ones, though scope longevity is very variable worldwide. New scopes usually last four times more than refurbished ones and single-use ureterorenoscopes have good resilience throughout long cases. Longer scope longevity is achieved with Cidex and if a dedicated nurse takes care of the sterilization process. The main surgical factors that negatively impact device longevity are lower pole pathologies, large stone burden and non-use of a ureteral access sheath. We have built a comprehensive fi nancial costeffective decision model to fl exible ureteroscope acquisition. CONCLUSIONS: The cost-effectiveness of a fl exible ureteroscopy program is dependent of several aspects. We have developed a equation to allow a literature-based and adaptable decision model to every interested stakeholder. Disposable devices are already a reality and will progressively become the standard as manufacturing price falls.

Sporadic primary hyperparathyroidism and stone disease: a comprehensive metabolic evaluation before and after parathyroidectomy.

OBJECTIVES: To characterize the stone risk and the impact of parathyroidectomy on the metabolic profile of patients with primary hyperparathyroidism (PHPT) and urolithiasis. PATIENTS AND METHODS: We analysed the prospectively collected charts of patients treated at our stone clinic between January 2001 and January 2016 searching for patients with PHPT and urolithiasis. Imaging evaluation of the kidneys, bones and parathyroid glands was assessed. We analysed the demographic data, serum and urinary variables before and after parathyroidectomy. We used a paired t-test, Fisher's test, Spearman's test and anova in the statistical analysis. RESULTS: A total of 51 patients were included. The mean patient age was 57.1 ± 12.1 years and 82.4% were women. Before parathyroidectomy, mean calcium and parathyroid hormone (PTH) levels were 11.2 ± 1.0 mg/dL and 331 ± 584 pg/dL, respectively. Hypercalcaemia was present in 84.3% of patients. All eight patients with normal calcium levels had elevated PTH levels. Only two patients did not have PTH above the normal range, although both had elevated calcium levels. The most common urinary disorders were low urinary volume (64.7%), hypercalciuria (60.8%), high urinary pH (41.2%) and hypocitraturia (31.4%). After parathyroidectomy, the number of patients with hypercalcaemia (n = 4; 7.8%), elevated PTH (n = 17; 33.3%) and hypophosphataemia (n = 3; 5.9%) significantly decreased (P < 0.001). The number of urinary abnormalities decreased and there was a reduction in urinary calcium (P < 0.001), pH (P = 0.001) and citrate levels (P = 0.003). CONCLUSION: Individuals with PHPT and nephrolithiasis frequently have elevated baseline PTH and calcium levels. Low volume, hypercalciuria, high urinary pH, and hypocitraturia are the most frequent urinary disorders. Parathyroidectomy is effective in normalizing serum calcium and PTH levels, although other urinary metabolic may persist. Patients should be monitored for the need for citrate supplementation.

Supine percutaneous nephrolitotripsy in septuagenarian and octogenarian patients: outcomes of a case-control study.

INTRODUCTION: Currently, there is a paucity of data evaluating the outcomes of supine percutaneous nephrolithotomy (PCNL) in septuagenarian and octogenarian patients. In this study we aim to compare the outcomes of supine PCNL in elderly patients with those of younger population. MATERIAL AND METHODS: A matched case-control study was performed from January 2009 through December 2015 using our prospectively collected kidney stone database. Case group was composed of patients with age greater than 70 years. Control group included patients with less than 70 years old. Patients were randomly matched based on Guy's Stone Score as a surrogate of case complexity. RESULTS: Fifty-four patients were enrolled in this study, 18 cases and 36 controls. There were no significant differences in gender and body mass index between groups. There were significantly more ASA 3 patients in septuagenarian and octogenarian patients (p = 0.012). Mean Charlson comorbidity index was significantly higher in septuagenarian and octogenarian patients (p = 0.041). Regarding PCNL technique, there were no differences in number of accesses, number of supra-costal accesses, and operative time. There was no significant difference in stone-free rate, nephrostomy tube time, complication rate, mean decrease in hemoglobin level, and need of blood transfusion. Hospital stay time (days) was longer in case group (4.0 +/- 1.7 versus 2.4 +/- 1.1 days; p = 0.002). CONCLUSION: Septuagenarian and octogenarian patients have similar complication and stone-free rates compared to younger patients, although they demand a longer length of hospital stay.

Supracostal punctures in supine percutaneous nephrolithotomy are safe.

INTRODUCTION: The feasibility and safety of supracostal punctures in supine percutaneous nephrolithotomy (PCNL) are still controversial. In this study we aim to compare success and complication rates from prone and supine PCNL with at least one supracostal puncture. MATERIAL AND METHODS: We reviewed our electronic database for all supracostal PCNLs performed in our institution from February 2008 to September 2013. Patients were enrolled in the study if at least one supracostal puncture was required during surgery. Patients' demographics data, stone characteristics, intra and postoperative data, and success on first postoperative day CT were compared. RESULTS: A total of 132 procedures were included in the analysis. Twenty-eight PCNLs were performed in supine position (21.2%), while 104 were done in prone position (78.8%). Patient's demographics and distribution of stones based on Guy's Score were similar between groups. Mean operative time and blood transfusion rate were not statistically different. There was no significant difference in the success rate (63.5% prone versus 71.4% supine, p = 0.507). Major complication rate (Clavien ≥ 3) was 16.3% in the prone group versus 3.6% in the supine group (p = 0.119). CONCLUSIONS: Supracostal punctures are safe and feasible in supine PCNL. It does not add additional risks and might provide equivalent success rates when compared to prone PCNLs.

Robot - assisted laparoscopic retroperitoneal lymph node dissection in testicular tumor.

INTRODUCTION AND OBJECTIVE: Retroperitoneal lymph node dissection (RPLND) is indicated for patients with non-seminomatous germ cell tumor (NSGCT) with residual disease after chemotherapy. Although the gold standard approach is still the open surgery, few cases of robot-assisted laparoscopic RPLND have been described. Herein, we aim to present the surgical technique for robot-assisted laparoscopic RPLND. PATIENT AND METHOD: A 30 year-old asymptomatic man presented with left testicular swelling for 2 months. Physical examination revealed an enlarged and hard left testis. Alpha-fetoprotein (>1000ng/mL) and beta-HCG (>24.000U/L) were increased. Beta-HCG increased to >112.000U/L in less than one month. The patient underwent a left orchiectomy. Pathological examination showed a mixed NSGCT (50% embryonal carcinoma; 30% teratoma; 10% yolk sac; 10% choriocarcinoma). Computed tomography scan revealed a large tumor mass close to the left renal hilum (10x4x4cm) and others enlarged paracaval and paraortic lymph nodes (T2N3M1S3-stage III). Patient was submitted to 4 cycles of BEP with satisfactory response. Residual mass was suggestive of teratoma. Based on these findings, he was submitted to a robot-assisted RPLND. RESULTS: RPLND was uneventfully performed. Operative time was 3.5 hours. Blood loss was minimal, and there were no intra- or postoperative complications. The patient was discharged from hospital in the 1st postoperative day. Pathological examination showed a pure teratoma. After 6 months of follow-up, patient is asymptomatic with an alpha-fetoprotein of 2.9ng/mL and an undetectable beta-HCG. CONCLUSION: Robot-assisted laparoscopic RPLND is a feasible procedure with acceptable morbidity even for post chemotherapy patients when performed by an experienced surgeon.

What is the quickest scoring system to predict percutaneous nephrolithotomy outcomes? A comparative study among S.T.O.N.E score, guy's stone score and croes nomogram.

OBJECTIVE: To compare the application time and the capacity of the nomograms to predict the success of Guy's Stone Score (GSS), S.T.O.N.E. Nephrolithometry (STONE) and Clinical Research Office of the Endourological Society nephrolithometric nomogram (CROES) of percutaneous nephrolithotomy (PCNL), evaluating the most efficient one for clinical use. MATERIALS AND METHODS: We studied 48 patients who underwent PCNL by the same surgeon between 2010 and 2011. We calculated GSS, STONE and CROES based on preoperative non-contrast computed tomography (CT) images and clinical data. A single observer, blinded to the outcomes, reviewed all images and assigned scores. We compared the application time of each nomogram. We used an analysis of variance for repeated measures and multiple comparisons by the Tukey test. We compared the area under the ROC curve (AUC) of the three nomograms two by two to determine the most predictive scoring system. RESULTS: The immediate success rate was 66.7% and complications occurred in 16.7% of cases. The average operative time was 122 minutes. Mean application time was significantly lower for the GSS (27.5 seconds) when compared to 300.6 seconds for STONE and 213.4 seconds for CROES (p<0.001). There was no significant difference among the GSS (AUC=0.653), STONE (AUC=0.563) and CROES (AUC=0.641) in the ability to predict immediate success of PCNL. CONCLUSIONS: All three nomograms showed similar ability to predict success of PCNL, however the GSS was the quickest to be applied, what is an important issue for routine clinical use when counseling patients who are candidates to PCNL.