Pooled-analysis of efficacy and safety of minimally invasive versus standard percutaneous nephrolithotomy.

BACKGROUND: This study aimed to assess the efficacy and safety of minimally invasive percutaneous nephrolithotomy (MPCNL) versus standard percutaneous nephrolithotomy in patients with renal and upper ureteric stones. METHODS: We conducted a pooled analysis on randomized controlled trials (RCTs). The eligible RCTs were selected from the following databases: MEDLINE, Embase, Web of Science, and the Cochrane Library. The reference lists of retrieved studies were also investigated. RESULTS: Our analysis included 10 RCTs with 1612 patients. Pooled data from 10 RCTs revealed the following: stone-free rate (odds ratio = 1.46, 95% confidence interval (CI) [1.12,1.88], P = .004), operative time (mean difference [MD]  = 4.10, 95% CI [-1.37,9.56], P = .14), length of hospital stay (MD = -15.31, 95% CI [-29.43,-1.19], P = .03), hemoglobin decrease (MD = -0.86, 95% CI [-1.19,-0.53], P < .00001), postoperative fever (MD = 0.83, 95% CI [0.49,1.40], P = .49), and urine leakage (MD = 0.59, 95% CI [0.25,1.37], P = .22). Besides, we performed sub-group analysis based on vacuum suction effect and multiple kidney stones. For vacuum suction effect, it revealed the following: stone-free rate in vacuum suction group (P = .007) and in non-vacuum suction group (P = .19). Operative time in vacuum suction group (P = .89), non-vacuum suction group (P = .16). Postoperative fever in vacuum suction group (P = .49), non-vacuum suction group (P = .85). CONCLUSION: This pooled analysis indicated that MPCNL was a safe and effective method for treating renal stones compared with standard percutaneous nephrolithotomy. Besides, the vacuum suction effect in MPCNL played a more important role. When it comes to multiple or staghorn stones, the longer operative time in MPCNL could not be ignored.

Inter-Resident Variability in Urologic Operative Case Volumes Over Time: A Review of the ACGME Case Logs From 2009 to 2016.

OBJECTIVES: To assess the effect of the changing landscape of urologic residency education and training on resident operative exposure and inter-resident variability. METHODS: The Accreditation Council for Graduate Medical Education (ACGME) case logs for graduating urology chief residents were reviewed from Academic Year (AY) 2009-2010 to 2016-2017. Cases were stratified into the 4 ACGME categories - general urology, endourology, oncology, and reconstruction. Linear regression models analyzed the association between training year, volume, and type of cases performed. Inter-resident variability in case exposure was calculated by the difference between the ACGME reported 10th and 90th percentiles. RESULTS: During the study period, the mean number of cases performed per resident was 1092 (standard deviation 32.7). Although there was no significant change in total case volume, there were changes within case categories. Endoscopic, retroperitoneal oncology, and male reconstruction case volume all increased significantly (Δ20.1%, Δ 5.1%, Δ 8.2%, respectively, all P < .05). This was balanced with a concomitant decrease in pelvic oncology and female reconstruction cases (Δ 10.0% and Δ 14.5%, respectively, both P < .05). There was a 27.8% increase in laparoscopic/robotic cases (P < .001). The ratio difference between the 10th percentile and 90th percentile ranged from a low of 2.5 for retroperitoneal oncology cases to a high of 5.2 for extracorporeal shock wave lithotripsy and percutaneous nephrolithotomy. CONCLUSION: From AY2009-2010 to 2016-2017, residency case volume has remained constant, but there has been a change in types of cases performed and proliferation of minimally invasive techniques. Significant variability of inter-resident operative experience was noted.

An easy risk stratification to recommend the optimal patients with 2-3 cm kidney stones to receive retrograde intrarenal surgery or mini-percutaneous nephrolithotomy.

To create an easy risk stratification to recommend the optimal subset of patients with 2-3 cm kidney stones to receive retrograde intrarenal surgery (RIRS) or mini-percutaneous nephrolithotomy (MPCNL). A retrospective patient cohort was reviewed and compared (RIRS, n = 147 and MPCNL, n = 129). Overall, RIRS group obtained a lower SFR (66% vs. 93.3%, p < 0.001) compared to MPCNL group. The RIRS group had more overall complication (12.2% vs. 8.5%) and more urosepsis (2.7% vs. 1.6%) than the MPCNL group, although there was no statistical significance. However, two patients in MPCNL group underwent embolization to treat perioperative bleeding. On multivariate analysis for RIRS group, lower calyx involved [OR 2.67], multiple calyces [OR 4.49], severe hydronephrosis [OR 2.38] were three significant predictors of SFR, which decreased from 88.8%, 70.3%, 52.1% to 25% corresponding to patients with 0, 1, 2, 3 risk predictors, respectively (p = 0.008), with a good predictive accuracy (AUC = 0.657; p = 0.002). When patients with no risk factor and patients undergoing RIRS had a similar high SFR and no possibility of bleeding, compared to matched patients undergoing MPCNL. Although generally RIRS showed a lower SFR for 2-3 cm stones compared to MPCNL, our easy risk stratification can recommend the optimal subset of patients with 2-3 cm kidney stones to receive RIRS or MPCNL. When these patients with no above-mentioned risk factors, RIRS can be first considered as an alternative to PCNL because it might be potentially less invasive and achieve a similar very high stone-free rate.

Comparison of Scoring Systems in Predicting Success of Percutaneous Nephrolithotomy

Background: Scoring systems are useful to inform the patients about the success and complication rates of the operation prior the surgery. Aims: To determine the applicability of the popular scoring systems (Guy's, stone size, tract length, obstruction, number of involved calices, and essence/stone density and Clinical Research Office of the Endourological Society) by means of examining preoperative data of patients treated with percutaneous nephrolithotomy. Study Design: Cross sectional study. Methods: We retrospectively reviewed files of the patients who had undergone percutaneous nephrolithotomy in our center between 2011 and 2015. Excluded from the study were patients aged <18 years, and those who were not assessed preoperatively with computed tomography. Preoperative computed tomography images of all patients were assessed by a single observer, and patients were graded based on three scoring system. Demographic data were analyzed along with perioperative data (operation, fluoroscopy, length of hospital stay, changes in hematocrit values, location, and number of access sites, stone-free and complication rates). Results: A total of 298 patients who had been treated with 300 procedures were enrolled into the study. Mean age, stone burden, number of stones, and density were 48.1±12.9 years, 663.5±442.8 mm2, 1.8±1.1 and 888.3±273 HU respectively. Scores of the cases based on Guy's, stone size, tract length, obstruction, number of involved calices, and essence/stone density, and Clinical Research Office of the Endourological Society scoring system were calculated as 2, 7.6, and 222.1 points respectively. 81.6% of the patients were stone-free. Complications were detected in 30 (9.9%) patients. Based on receiver operating characteristic curve analysis a positive correlation was detected between success rate and scoring systems, i.e., Guy's (p=<0.001, r=-0.309), stone size, tract length, obstruction, number of involved calices, and essence/stone density (p=<0.001, r=-0.295), and Clinical Research Office of the Endourological Society (p=<0.001, r=0.426). The Clinical Research Office of the Endourological Society scoring system had the highest predictive value. The sensitivity rates rates for Guy's, Clinical Research Office of the Endourological Society and Stone scoring system were as 78.78%, 80% and 82.34% respectively. Conclusion: All of scoring systems predicted correctly the success of the percutaneous nephrolithotomy procedures. The Clinical Research Office of the Endourological Society scoring system had the highest predictive value.

Differences in the percutaneous nephrolithotomy practice patterns among Latin American urologists with and without endourology training

ABSTRACT Purpose: Although the worldwide percutaneous nephrolithotomy (PCNL) practice pat- terns determined via a survey sent to members of the Endourological Society have been published, differences in PCNL practice patterns among Latin American urologists based on endourological or lithiasis training have not been published. To determine the PCNL practice patterns among Latin American urologists with and without training in endourology. Materials and Methods: The SurveyMonkey® web platform was used to develop a 27-item survey on PCNL for the treatment of renal stones, and the survey was sent via e- -mail and other electronic media to 2000 urologists from 15 Latin American countries. Endourology-trained (group 1) and nontrained urologists (group 2) were analyzed. The group results were compared using the chi-squared and Fisher's exact tests. SPSS version 20 for Windows was used for all analyses. Results: A total of 331 urologists responded to the survey (rate of 16.55%): 221 (66.7%) in group 1 and 110 (33.2%) in group 2). In groups 1 and 2, 91.9% and 63.2% performed PCNL, respectively: 85.1% and 58.5% used preoperative tomography, respectively; 12.7% and 4.7% used preoperative nephrolitometry nomograms, respectively: 45.2% and 32.1% used endoscopic combined intrarenal surgery, respectively: 68.3% and 38.7% used mul- tiple percutaneous tract realization, respectively: and 19.9% and 5.7% used minimally invasive PCNL, respectively (all p=0.0005). Conclusions: Statistically significant differences were observed in PCNL practice patterns of Latin American urologists with and without training in endourology. Specific training in endourology significantly influence the practice patterns of Latin American urologists.

Management of staghorn renal stones.

Staghorn stones are large branching stones that fill part of all of the renal pelvis and renal calyces and they can be complete or partial depending on the level of occupancy of the collecting system. Although kidney stones are commoner in men, staghorn stones are less often reported in men compared to women and they are usually unilateral. Due to the significant morbidity and potential mortality attributed to staghorn stones, prompt assessment and treatment is mandatory. Conversely, conservative treatment has been shown to carry a mortality rate of 28% in 10-year period and 36% risk of developing significant renal impairment. Staghorn stones are, therefore, significant disease entity that should be managed aggressively and effectively. Generally, the gold standard treatment for staghorn stones is surgical with a view to achieve stone-free collecting system and preserve renal function. Percutaneous nephrolithotomy should be the recommended first-line treatment for staghorn stones. Other non-surgical options are usually considered in combination with surgery or as monotherapy only if patients are surgically unfit. The decision for optimal treatment of staghorn stones should be individualized according to the circumstances of the patient involved and in order to do so, a closer look at the advantages and disadvantages of each option is necessary.

Differences in the percutaneous nephrolithotomy practice patterns among Latin American urologists with and without endourology training.

PURPOSE: Although the worldwide percutaneous nephrolithotomy (PCNL) practice patterns determined via a survey sent to members of the Endourological Society have been published, differences in PCNL practice patterns among Latin American urologists based on endourological or lithiasis training have not been published. To determine the PCNL practice patterns among Latin American urologists with and without training in endourology. MATERIALS AND METHODS: The SurveyMonkey® web platform was used to develop a 27- item survey on PCNL for the treatment of renal stones, and the survey was sent via e-mail and other electronic media to 2000 urologists from 15 Latin American countries. Endourology-trained (group 1) and nontrained urologists (group 2) were analyzed. The group results were compared using the chi-squared and Fisher's exact tests. SPSS version 20 for Windows was used for all analyses. RESULTS: A total of 331 urologists responded to the survey (rate of 16.55%): 221 (66.7%) in group 1 and 110 (33.2%) in group 2). In groups 1 and 2, 91.9% and 63.2% performed PCNL, respectively; 85.1% and 58.5% used preoperative tomography, respectively; 12.7% and 4.7% used preoperative nephrolitometry nomograms, respectively; 45.2% and 32.1% used endoscopic combined intrarenal surgery, respectively; 68.3% and 38.7% used multiple percutaneous tract realization, respectively; and 19.9% and 5.7% used minimally invasive PCNL, respectively (all p=0.0005). CONCLUSIONS: Statistically significant differences were observed in PCNL practice patterns of Latin American urologists with and without training in endourology. Specific training in endourology significantly influence the practice patterns of Latin American urologists.

Comparison of the efficacy and safety of URSL, RPLU, and MPCNL for treatment of large upper impacted ureteral stones: a randomized controlled trial.

BACKGROUND: There are three minimally invasive methods for the management of large upper impacted ureteral stones: mini-percutaneous nephrolithotomy (MPCNL), transurethral ureteroscope lithotripsy (URSL), and retroperitoneal laparoscopic ureterolithotomy (RPLU). This study aimed to compare MPCNL, URSL, and RPLU, and to evaluate which one is the best choice for large upper impacted ureteral stones. METHODS: Between January 2012 and December 2015, at the Department of Urology, Huai'an First People's Hospital, 150 consecutively enrolled patients with a large upper impacted ureteral stone (>15 mm) were included. The patients were randomly divided (1:1:1) into the MPCNL, URSL, and RPLU groups. The primary endpoint was success of stone removal measured 1 month postoperatively and the secondary endpoints were intraoperative and postoperative parameters and complications. RESULTS: Fifteen patients needed auxiliary ESWL after URSL, and 3 patients after MPCNL, but none after RPLU. The stone clearance rate was 96% (48/50) in the MPCNL group and 72% (33/46) in the URSL group. In the RPLU group the stones were completely removed and the stone clearance rate was 100% (48/48) (P = 0.021 vs. URSL; P = 0.083 vs. MPCNL). Operation-related complications were similar among the three groups (all P > 0.05). Hospital stay was shorter in the URSL group compared with MPCNL (P = 0.003). Operation time was the shortest with URSL and the longest with MPCNL (all P < 0.05). CONCLUSIONS: MPCNL and RPUL are more suitable for upper ureteral impacted stones of >15 mm. URSL could be considered if the patient is not suitable for general anesthesia, or the patient requests transurethral uretroscopic surgery. TRIAL REGISTRATION: This study was registered with the Chinese Clinical Trial Registry (Registration number: ChiCTR-INR-17011507 ; Registration date: 2017-5-22).

Tract Sizes in Miniaturized Percutaneous Nephrolithotomy: A Systematic Review from the European Association of Urology Urolithiasis Guidelines Panel.

CONTEXT: Miniaturized instruments for percutaneous nephrolithotomy (PNL), utilizing tracts sized ≤22 Fr, have been developed in an effort to reduce the morbidity and increase the efficiency of stone removal compared with standard PNL (>22 Fr). OBJECTIVE: We systematically reviewed all available evidence on the efficacy and safety of miniaturized PNL for removing renal calculi. EVIDENCE ACQUISITION: The review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement. Since it was not possible to perform a meta-analysis, the data were summarized in a narrative synthesis. EVIDENCE SYNTHESIS: After screening 2945 abstracts, 18 studies were included (two randomized controlled trials [RCTs], six nonrandomized comparative studies, and 10 case series). Thirteen studies were full-text articles and five were only available as congress abstracts. The size of tracts used in miniaturized procedures ranged from 22 Fr to 4.8 Fr. The largest mean stone size treated using small instruments was 980mm2. Stone-free rates were comparable in miniaturized and standard PNL procedures. Procedures performed with small instruments tended to be associated with significantly lower blood loss, while the procedure duration tended to be significantly longer. Other complications were not notably different between PNL types. Study designs and populations were heterogeneous. Study limitations included selection and outcome reporting bias, as well as a lack of information on relevant confounding factors. CONCLUSIONS: The studies suggest that miniaturized PNL is at least as efficacious and safe as standard PNL for the removal of renal calculi. However, the quality of the evidence was poor, drawn mainly from small studies, the majority of which were single-arm case series, and only two of which were RCTs. Furthermore, the tract sizes used and types of stones treated were heterogeneous. Hence, the risks of bias and confounding were high, highlighting the need for more reliable data from RCTs. PATIENT SUMMARY: Removing kidney stones via percutaneous nephrolithotomy (PNL) using smaller sized instruments (mini-PNL) appears to be as effective and safe as using larger (traditional) instruments, but more clinical research is needed.