A randomized controlled study to analyze the safety and efficacy of percutaneous nephrolithotripsy and retrograde intrarenal surgery in the management of renal stones more than 2 cm in diameter

Risk factors for ureteroscopic lithotripsy: a case-control study and analysis of 385 cases of holmium laser ureterolithotripsy

Introduction

Ureteroscopic lithotripsy has become the first choice for the treatment of middle and lower ureteral stones, but it still has a certain rate of surgical failure. Here we aimed to determine the factors that may affect the success rate of holmium laser ureterolithotripsy (HLU) and provide the basis and guidance for its future use.

Aim

To evaluate the risk factors for HLU failure.

Material and methods

The clinical data of 385 patients undergoing holmium laser ureterolithotripsy from 2009 to 2012 were retrospectively reviewed to analyze the impact of gender, age, stone side, stone size, stone location, stone number, degree of hydronephrosis, stone impaction, previous extracorporeal shock lithotripsy (ESWL), and associated urinary tract infection (UTI) on the success or failure of surgery.

Results

Surgical success was achieved in 338 (87.8%) patients versus surgical failure in 47 (12.2%) patients. Univariate analysis revealed that the degree of hydronephrosis (p = 0.024), stone impaction (p = 0.003), stone location (p = 0.012), and previous ESWL (p = 0.037) were risk factors for surgical failure. Multivariate logistic regression revealed that stone impaction (odds ratio (OR) = 2.66; p = 0.018) and stone location (OR = 2.11; p = 0.013) were significantly associated with surgical failure. Since some cases of ureterostenosis developed postoperatively, we continued follow-up. The patients had the stent for a year and underwent regular follow-up checks until 5 years. No cases of ureterostenosis recurred.

Conclusions

Ureteroscopic lithotripsy is a safe procedure with few complications. Stone impaction and proximal location are the risk factors for its failure.

The efficacy of flexible ureteroscopy lithotripsy and miniaturized percutaneous nephrolithotomy for the treatment of renal and proximal ureteral calculi of ≤2 cm: A retrospective study

To assess the clinical effect of miniaturized percutaneous nephrolithotomy (MPCNL) and flexible ureteroscopy lithotripsy (FURL) for the treatment of renal and proximal ureteral calculi of ≤2 cm.A retrospective analysis was carried out on clinical data of 106 patients with kidney or upper urethral calculi. Among these patients, 58 underwent the MPCNL, and 48 received FURL. Stone-free rates, operating time, blood loss, hemoglobin drop, length of hospital stay, complications, and renal damage indexes were compared.The stone removal rates of the FURL and MPCNL groups were 81.25% versus 87.93% (p > .05). Although operating time was significantly shorter in the MPCNL group, hospital stays were significantly shorter in the FURL group. In addition, pooled analysis showed that mean estimated blood loss was significantly higher in the PCNL group but the hemoglobin decline of the FURL group and PCNL group had no significant difference. The PCNL group had no significant difference in complications compared to the FURL group. Differences on the creatinine levels and urea nitrogen levels before the operation and after the operation were not statistically significant.FURL is an effective method for treating renal stone. FURL not only had a similar stone-free rate as compared to MPCNL but also was associated with less blood loss and more favorable recovery time. However, FURL had a longer operative time.

Comparison of stone-free rates following shock wave lithotripsy, percutaneous nephrolithotomy, and retrograde intrarenal surgery for treatment of renal stones: A systematic review and network meta-analysis

OBJECTIVES

To perform a systematic review and network meta-analysis comparing stone-free rates following retrograde intrarenal surgery (RIRS), extracorporeal shock wave lithotripsy (SWL), and percutaneous nephrolithotomy (PCNL) treatments of renal stones.

MATERIALS AND METHODS

Clinical trials comparing RIRS, SWL, and PCNL for treatment of renal stones were identified from electronic databases. Stone-free rates for the procedures were compared by qualitative and quantitative syntheses (meta-analyses). Outcome variables are shown as risk ratios (ORs) with 95% credible intervals (CIs).

RESULTS

A total of 35 studies were included in this network meta-analysis of success and stone-free rates following three different treatments of renal stones. Six studies compared PCNL versus SWL, ten studies compared PCNL versus RIRS, fourteen studies compared RIRS versus SWL, and five studies compared PCNL, SWL, and RIRS. The quality scores within subscales were relatively low-risk. Network meta-analyses indicated that stone-free rates of RIRS (OR 0.38; 95% CI 0.22-0.64) and SWL (OR 0.12; 95% CI 0.067-0.19) were lower than that of PCNL. In addition, stone-free rate of SWL was lower than that of RIRS (OR 0.31; 95% CI 0.20-0.47). Stone free rate of PCNL was also superior to RIRS in subgroup analyses including ≥ 2 cm stone (OR 4.680; 95% CI 2.873-8.106), lower pole stone (OR 1.984; 95% CI 1.043-2.849), and randomized studies (OR 2.219; 95% CI 1.348-4.009). In rank-probability test, PCNL was ranked as No. 1 and SWL was ranked as No. 3.

CONCLUSIONS

PCNL showed the highest success and stone-free rate in the surgical treatment of renal stones. In contrast, SWL had the lowest success and stone-free rate.

Comparison of suctioning and traditional ureteral access sheath during flexible ureteroscopy in the treatment of renal stones

PURPOSE

To compare the efficiency and safety of suctioning ureteral access sheath (UAS) and traditional UAS during flexible ureteroscopy (FURS) for treatment of renal stones.

METHODS

Between January 2015 and December 2017, 165 patients who had renal stones successfully underwent FURS with suctioning UAS created by connecting a channel on the tail of the suctioning UAS to a vacuum device. The outcomes of these patients were compared with those of 165 patients undergoing FURS with traditional UAS using a 1:1 scenario matched-pair analysis. The matching parameters were age, gender and stone burden.

RESULTS

The baseline characteristics were homogeneous between the two groups. The suctioning UAS group had significantly higher SFR one day postoperatively (82.4% vs. 71.5%; P = 0.02), but SFR 1 month postoperatively was comparable in the two groups (P = 0.13). The incidence of overall complications was significantly higher in the traditional UAS group (24.8% vs 11.5%; P < 0.001). Regarding individual complications, the traditional UAS group was associated with a significantly higher incidence of fever (13.9% vs 5.5%; P = 0.009) and urosepsis requiring only additional antibiotics (6.7% vs 1.8%; P = 0.029). No significant difference was noted in the incidence of septic shock, hematuria, steinstrasse or ureteral stricture. The suctioning UAS group had significantly shorter operative time (49.7 + 16.3 min vs. 57.0 ± 14.0 min; P < 0.001).

CONCLUSIONS

Compared to traditional UAS during FURS for treating renal stones, suctioning UAS had the advantages of higher SFR 1 day postoperatively, a lower incidence of infectious complications and a shorter operative time. Further well-designed studies are required to confirm the results.

A stone pushed back to the collecting system - long therapeutic path in centers with limited access to flexible instruments

Introduction

Availability of flexible ureteroscopes is still limited in many countries and centers. Under such circumstances treating small stones pushed from the ureter to the kidney that pose a risk of symptomatic recurrence is controversial as it may require a number of surgical procedures to remove. The aim of this study was to assess the type and number of procedures used to treat stones relocated from the ureter to the collecting system in a high volume urological center with limited access to flexible instruments.

Materials and methods

Patients treated for ureteral stones in years 2013–2016 were retrospectively reviewed. All procedures performed after stone relocation were counted. Final stone status was determined by ultrasonography and radiography.

Results

Out of 75 patients with a stone relocated to the collecting system full follow-up was available for 66. In three patients (4%) the stone remained in the collecting system untreated. Seven patients (11%) passed their stones spontaneously. Active treatment was successful in 45 (68%), while it failed in 11 (17%) patients. Extracorporeal shock wave lithotripsy was used 132 times, semi-rigid ureteroscopy 21 times and percutaneous nephrolithotripsy 22 times – 175 procedures altogether (2.6 procedures/patient + accessory procedures such as JJ removal). Shockwave lithotripsy was effective in 7/41 patients, semi-rigid ureteroscopy in 18/21 and percutaneous nephrolithotripsy in 22/22 patients.

Conclusions

Treating small stones relocated from the ureter to the collecting system in centers not equipped with flexible endoscopes is inefficient, time-consuming or too invasive. Cost-effectiveness analysis should follow this study to obtain evidence for public health payers to change their policies.

The application of a single-use fiberoptic flexible ureteroscope for the management of upper urinary calculi

OBJECTIVE

To evaluate the clinical outcomes with a Chinese single-use fiberoptic flexible ureteroscope (YouCare Tech) from a prospective database.

MATERIALS AND METHODS

A prospective study was conducted in a single center in China between January 2016 and October 2017. All consecutive patients who underwent flexible ureteroscopy performed by YouCare flexible ureteroscope were analyzed. Patients' demographics, clinical characteristics, intraoperative parameters, postoperative complications, and stone-free rate were evaluated and recorded. Stone-free status was defined as no visible stones or clinically insignificant residual stones < 2 mm on a postoperative image study.

RESULTS

A total of 684 procedures were performed for 653 patients (31 patients had bilateral stones). A double J stent had been previously placed in 431 patients. The location of the calculi was upper calyx, middle calyx, lower calyx, and renal pelvis and proximal ureter in 74, 101, 211, 115, and 183 patients, respectively. The median operative time was 52 min. The postoperative stone-free rate for the first 2 weeks after surgery was 78.5%, which increased to 91.1% at the first month. The overall stone-free rate was 95.2%. The complication rate was minor and short-term, such as gross hematuria or flank pain.

CONCLUSION

YouCare flexible ureteroscope can be considered effective and safe in the treatment of both upper ureteral and renal stones in selected patients. Further evaluation of comparison with other FURS's surgical outcomes and cost-effectiveness analysis will help to present the best utility of this single-use FURS in clinical practice.

Research progress of percutaneous nephrolithotomy

Percutaneous nephrolithotomy (PCNL) is generally accepted as the gold standard treatment for the treatment of large kidney stones (> 2 cm). For nearly 40 years, with the continuous progress of technology and the constant updating of ideas, PCNL has made great progress. In this review, we discuss the current research progress, recent advancement and hot spot of the whole process of PCNL including anesthesia, position, puncture, dilation, lithotripsy approaches, perfusate, tube placement, hospitalization time, drug, treatment of residual stones, prognosis judgment and operation evaluation by summarizing the related research in this article.

Urinary Stone Disease: Diagnosis, Medical Therapy, and Surgical Management

Clinical suspicion of urolithiasis should be evaluated with low-dose computed tomography as the first-line imaging modality for nonpregnant, adult patients. A period of observation may be appropriate for ureteral stones less than 10 mm, and medical expulsive therapy may be beneficial for facilitating passage of distal ureteral stones. Regardless of stone type, patients should adhere to a low-sodium diet and attempt to achieve a urine volume of more than 2.5 L daily. Individuals with calcium stones should maintain a normal calcium diet, and if stones persist, citrate therapy or thiazide diuretics in the setting of hypercalciuria may be indicated.

Miniaturized percutaneous nephrolithotomy versus retrograde intrarenal surgery in the treatment of renal stones with a diameter <15 mm: A 3-year open-label prospective study

Aim

The aim of this study is to compare the outcomes of miniaturized percutaneous nephrolithotomy (mini-perc) and retrograde intrarenal surgery (RIRS) in management of renal stones with a diameter <15 mm.

Materials and Methods

This was an open-label prospective study that included a total of 80 cases underwent mini-perc (n = 40) and RIRS (n = 40) between July 2014 and August 2017. The primary outcome objective was stone-free rate, retreatment rate, complications, hospital stay, operative time, and reduction in hemoglobin level. Data were analyzed using SPSS version 16.0 Software.

Results

Overall, 80 patients were enrolled in this study. The mean age was 40.12 and 38.20 years, and the mean stone size was 1.15 and 1.30 cm in mini-perc and RIRS group, respectively. Majority of the study participants were males. Overall, mini-perc and RIRS had stone clearance rates of 100% and 95.4%, respectively. Two patients required retreatment in RIRS group. The duration of hospital stay and the rate of complication was similar in both the groups. Operative duration was more in RIRS group. Decrease in hemoglobin level was more in mini-perc group.

Conclusions

Results demonstrated that both modalities were associated with high stone clearance rates with minimal complications. RIRS was associated with less reduction in hemoglobin and could be used as standard treatment modality for small renal calculi.

Systematic review and meta-analysis to compare success rates of retrograde intrarenal surgery versus percutaneous nephrolithotomy for renal stones >2 cm: An update

BACKGROUND

We performed a systematic review and meta-analysis comparing stone-free rates between retrograde intrarenal surgery (RIRS) and percutaneous nephrolithotomy (PCNL), using updated, more reliable evidence.

MATERIALS AND METHODS

Randomized controlled trials comparing RIRS and PCNL for >2 cm stones were identified from electronic databases. Stone-free rates for the procedures were compared by qualitative and quantitative syntheses (meta-analyses). Outcome variables are shown as risk ratios (RRs) with 95% confidence intervals (CIs).

RESULTS

Eleven articles were included in this study. Most recently published studies exhibited relatively low quality during quality assessment. For the meta-analysis comparing success (stone-free) rates between PCNL and RIRS, the forest plot using the random-effects model showed an RR of 1.11 (95% CI 1.02-1.21, P < .014) favoring PCNL. After determining the among-study heterogeneity, subgroup analysis was performed of 9 studies with less heterogeneity: the stone-free rate of PCNL was superior to that of RIRS using a fixed-effect model (RR 1.07, 95% CI 1.01-1.14, P < .019) for these studies.

CONCLUSIONS

RIRS can be a safe and effective procedure for selected patients with large renal stones. However, in this meta-analysis, the postoperative stone-free rate of PCNL was higher than that of RIRS in patients with >2 cm renal stones.

Clinical efficacy of percutaneous nephrolithotomy versus retrograde intrarenal surgery for pediatric kidney urolithiasis: A PRISMA-compliant article

BACKGROUND

Percutaneous nephrolithotomy (PCNL) and retrograde intrarenal surgery (RIRS) are widely used for pediatric upper tract stones; however, comparisons of their clinical efficacies are needed.

METHODS

Literature searches for relevant articles were performed using PubMed, the Cochrane Central Register of Controlled Trials, Embase and the China CNKI database. Study quality was assessed by Jadad and Newcastle-Ottawa Scales. Standard mean differences (SMDs) or odds ratios (OR), and 95% confidential intervals (95% CIs) were pooled for meta-analysis. In addition, data was evaluated the quality of the body of evidence by means of grading of recommendations assessment, development, and evaluation (GRADE).

RESULTS

Data from 4 studies (231 PCNL, 212 RIRS cases) were analyzed. There was no significant difference in operation time (SMD: 1.39; 95% CIs: -0.049 to 2.82; P = .058), overall stone-free rate (OR: 3.72; 95% CIs: 0.55-25.22; P = .18), or complication rate (OR: 1.92; 95% CIs: 0.90-4.07; P = .091). PCNL cases had longer hospital stays (SMD: 1.22; 95% CIs: 0.95-1.50; P < .001), but showed a higher stone-free rate for stones greater than 20 mm (OR: 6.38; 95% CIs: 1.83-22.22; P = .004). For stones less than 20 mm, however, no significant difference between PCNL and RIRS was found (OR: 0.92; 95% CIs: 0.33-2.55; P = .87). The quality of evidence based on the GRADE system was low.

CONCLUSION

Results of our systematic review and meta-analysis suggest that, for the treatment of larger kidney stones (>20 mm) in pediatric patients, PCNL is a better option due to its higher stone-free rate, although RIRS may be associated with shorter hospital stays. A large-scale clinical trial is necessary to validate our findings.

The application of a novel integrated rigid and flexible Nephroscope in percutaneous nephrolithotomy for renal staghorn stones

Background

Renal staghorn stones are challenging for urologists to ensure maximum stone clearance and minimal morbidity. Percutaneous nephrolithotomy (PCNL) has become the gold standard treatment for renal staghorn stones. To assess the safety and efficacy of a novel integrated rigid and flexible percutaneous nephroscope(Rigi-flex nephroscope) in PCNL for renal staghorn stones.We present our initial experience with this new technique.

Methods

From March to July 2016, a prospective analysis of 3 patients with staghorn stones treated with Rigi-flex nephroscope in PCNLunder totally ultrasound guidance by paravertebral block (PVB) anesthesia was done. PCNL was performed with the rigid section of a 13-Fr Rigi-flex nephroscope firstly and the stones were disintegrated into fragments by holmium laser.Then the stones were removed by active flushout, followed by a search for residual stones in other inaccessible calyces with the flexible section. Finally, the residual stones were disintegrated into small fractions by holmium laser in situ or repositioned with a set of disposable retrieval baskets to pelvic or other accessible areas. The whole procedure was accomplished via only one nephrostomy tract. The operating time, stone-free rates (SFR), postoperative hemoglobin drop, complications, length of hospitalization, were recorded.

Results

The operation time were 89, 62 and 45 min, respectively, the postoperative hemoglobin drop was 1, 0.8 and 0.9 mg/dl, respectively.The postoperative Kidney-Ureter-Bladder (KUB) radiograph of the three patients showed no residual fragment >3 mm. No patients needed blood transfusion and suffered significant complications. The length of hospitalization was 9, 6 and 4 days, respectively. No patient needed multiple tracts PCNL or staged auxiliary measures one month after the operation.

Conclusions

The application of Rigi-flex nephroscope in PCNL under ultrasound guidance for staghorn stones has its unique advantages as monotherapy with increasing procedural stone free rate (SFR) via single nephrostomy tract, hence there is less morbidity as it does not require additional tracts dilation and staged auxiliary procedures combination. However, SFR should also be evaluated at a longer follow-up, particularly for staghorn stone, further large-scale multicenter prospective clinical trial are needed to verify its feasibility.

Predictive factors of bleeding among pediatric patients undergoing percutaneous nephrolithotomy

The purpose of this study is to determine the perioperative risk factors for increased blood loss in children undergoing percutaneous nephrolithotomy (PCNL).We retrospectively reviewed the data on pediatric patients who had undergone PCNL for stone disease in our department. Blood loss estimation was quantified by measuring the changes in hematocrit plus the volume of red blood cells transfused. Univariate and multivariate linear regression analyses were performed to evaluate risk factors associated with increased blood loss after pediatric PCNL. Variables included patient, stone, and treatment parameters. The study group consisted of 105 renal units in 97 children with a median (interquartile range) age of 5 (3-9) years. On univariate linear regression analysis female gender (p = 0.030), absence of hydronephrosis (p = 0.013), increasing stone burden (p = 0.002), staghorn stone type (p = 0.013), multi-tract access (p < 0.001), and prolonged operative time (p < 0.001) were significantly associated with increased blood loss after pediatric PCNL. However, multivariate linear regression analysis demonstrated that the only independent risk factors for increased blood loss following pediatric PCNL were degree of hydronephrosis (B -1.329, 95% CI -2.451 to -0.208, p = 0.021), number of tracts (B 2.545, 95% CI 0.221-4.869, p = 0.032), and operative time (B 0.031, 95% CI 0.008-0.053, p = 0.007). Identifying pediatric patients at increased risk of bleeding following PCNL is crucial to minimize morbidity and hospital stay, and thus, the cost of treatment. Our study demonstrated that degree of hydronephrosis, number of tracts and operative time are important factors in reducing blood loss during pediatric PCNL.

A prospective randomized comparison of micropercutaneous nephrolithotomy (Microperc) and retrograde intrarenal surgery (RIRS) for the management of lower pole kidney stones

OBJECTIVE

To make a comparison between the safety and efficacy of micropercutaneous nephrolithotomy (microperc) and retrograde intrarenal surgery (RIRS) for the management of lower pole kidney stones up to 15 mm.

PATIENTS AND METHODS

60 patients presenting with solitary lower pole kidney stones up to 15 mm were included in the study between March 2013 and December 2015. Patients were randomized into Microperc or RIRS groups with computer-generated numbers.

RESULTS

The mean stone size was 10.6 (5-15) and 11.5 (7-15) mm for Microperc and RIRS groups, respectively (P = 0.213). In the Microperc group, the scopy time was 158.5 s, while in the RIRS group, the scopy time was 26.6 s (P = 0.001). The hospitalization period in the Microperc group was 542 h, while it was 19 h in the RIRS group (P = 0.001). No statistical differences were observed during the operating time, pre-operative-post-operative hemoglobin (Hb), serum creatinine, and estimated glomerular filtration speed (e-GFR) values and stone-free rates. No intraoperative complications were observed in either of the groups, while post-operative complications were observed in six patients in Microperc Group and five patients belonging to the RIRS Group (P = 0.922).

CONCLUSIONS

Both Microperc and RIRS are safe and effective alternatives, and have similar stone clearance and complication rates for the management of lower pole kidney stones up to 15 mm in diameter. However, prolonged hospital stay and scopy times are the main disadvantages of Microperc and further research is needed to evaluate the renal tubular damages caused by both of these methods.

To Dust or Not To Dust: a Systematic Review of Ureteroscopic Laser Lithotripsy Techniques

PURPOSE OF REVIEW

This review discusses factors affecting outcomes during ureteroscopy (URS) with laser lithotripsy (LL), explores specific clinical challenges to the efficacy of URS LL, and reviews the available literature comparing the dusting and basketing approaches to URS LL.

RECENT FINDINGS

Data show high stone-free rates with URS LL in all locations of the urinary tract and with all stone types and sizes. Recent data comparing LL with dusting versus basketing suggest higher rates of residual fragments with dusting but less utilization of ureteral access sheaths and potentially shorter operative times. Differences in postoperative complications, re-intervention rates, and other outcome parameters are not yet clear. Interpretation of published data is problematic due to variability in laser settings, follow-up intervals, and definitions for what constitutes stone-free status. URS has overtaken shock wave lithotripsy in the last decade as the most commonly utilized surgical approach for treating urolithiasis. Two primary strategies have emerged as the most common techniques for performing LL: dusting and basketing. There is a relative paucity of data examining the difference in these techniques as it pertains to peri-operative outcomes and overall success. We attempt to synthesize this data into evidence-based and experience-based recommendations.

Laparoscopic-assisted mini percutaneous nephrolithotomy for treatment of large calculi in pelvic ectopic kidney

We report two cases of male patients with pelvic ectopic kidney with large stones cleared with laparoscopic-assisted minimally invasive percutaneous nephrolithotomy (Mini-PERC) and holmium laser. These are the first cases of Mini-PERC done for pelvic ectopic kidney reported thus far.

[Evaluation of the operating results and costs associated with the implementation of a flexible ureteroscopy activity within a university hospital center]

INTRODUCTION

The increasing use of flexible ureteroscopy (USSR) sets the cost problems inevitably associated with the fragility of these endoscopes. The aim of this work is to clear from a recent example (universitary hospital) results, costs during the implementation of this technique.

MATERIAL AND METHODS

This is a retrospective study conducted from December 2012 (date of introduction of the activity) in March 2015 concerning the USSR made in a French universitary hospital for stone disease. In this analysis, the cost of consumables was not evaluated, nor the costs of the operating theater or hospitalization.

RESULTS

One hundred forty-one hundred and thirteen patients USSR were conducted by seven surgeons. Seventeen breakages and failures have been identified and have led to the sending of the endoscope for repair. Breakage rate and failure was 12%. All failures were treated with a standard exchange of the device (including 4 standard exchanges made under warranty). The estimated average cost of outages was 3600 euros. This represents an average cost per procedure of about 625 euros (acquisition plus cost of failures) without counting the costs of sterilization or high-level disinfection. The impossibility of relocating the lower calyx stones is associated with an excess risk of breakage (odd ratio: 2.92 CI95: [1.02; 8.37]).

CONCLUSION

This study is novel because it focuses on the cost of implementing a technique in a French university hospital. The use of flexible ureteroscope to unique uses might be an interesting source of savings in the implementation of this technique. This remains to be evaluated.

LEVEL OF EVIDENCE

5.

Comparative analysis between percutaneous nephrolithotomy and flexible ureteroscopy in kidney stones of 2-3cm

INTRODUCTION

To compare percutaneous nephrolithotomy and flexible ureterorenoscopy for treating kidney stones between 2 and 3cm.

MATERIAL AND METHODS

A prospective, comparative, nonrandomised study was conducted with 108 patients with kidney stones between 2 and 3cm. Fifty-four patients underwent percutaneous nephrolithotomy and 54 underwent flexible ureteroscopy. We compared the following variables: lithiasis-free rate (%), surgical time, the need for an auxiliary process, postoperative complications, hospital stay, readmission rates and recovery time.

RESULTS

There were no differences in the lithiasis-free rate between the 2 surgical techniques (76% for ureteroscopy vs. 87% for nephrolithotomy; P=.1) or in the complications (29% for nephrolithotomy vs. 27% for ureteroscopy; P=.4). A larger number of auxiliary process were needed for the ureteroscopy group (20%) than for the nephrolithotomy group (7%) (P=.04). The surgical time was longer for the nephrolithotomy group (121±52min) than for the ureteroscopy group (93±42min) (P=.004). The ureteroscopy group had shorter hospital stays (2.1±1.6 vs. 3.9±1.9 days; P=.002), shorter convalescence (8.1±4.9 vs. 13.3±4.2 days; P=.005) and higher readmission rates (7.4% vs. 0%, P=.05) than the nephrolithotomy group.

CONCLUSIONS

Nephrolithotomy and ureteroscopy have similar efficacy for treating kidney stones measuring 2-3cm, with no differences in complications. Ureteroscopy results in shorter hospital stays, quicker recoveries but more readmissions and a greater need for auxiliary procedures.

The efficacy of performing shockwave lithotripsy before retrograde intrarenal surgery in the treatment of multiple or large (≥1.5 cm) nephrolithiasis: A propensity score matched analysis

Purpose

To investigate the effect of performing shockwave lithotripsy (SWL) before retrograde intrarenal surgery (RIRS) on the treatment outcomes of patients with nephrolithiasis.

Materials and Methods

The data of 189 patients with renal stones who underwent RIRS from July 2007 to July 2014 was reviewed retrospectively. Patients with stones larger than 1.5 cm were recommended to undergo SWL before RIRS. Patients were divided into 2 groups based on whether the preoperative SWL was performed (group 1, n=68) or not (group 2, n=121). The cohorts of the 2 groups cohorts were matched 1:1 using propensity score analysis. Patient, stone characteristics, operative parameters, and stone-free rates were compared.

Results

Patients in groups 1 and 2 were matched with respect to stone size, number, and location, leaving 57 patients in each group. After matching, no differences were identified between the 2 groups regarding age, body mass index, sex, stone composition, density and multiplicity. Compared to group 2 patients, patients in group 1 had fewer number of procedures performed (1.10 vs. 1.26, p=0.045) and higher stone-free rate (89.4% vs.73.6%, p=0.039). In multivariate analysis, Non lower calyceal location (odd ratio [OR], 8.215; 95% confidence interval [CI], 1.782–21.982; p=0.041), stone size (OR, 6.932; 95% CI, 1.022–18.283; p<0.001), and preoperative SWL (OR, 2.210; 95% CI, 1.058–7.157; p=0.019) were independent factors predicting a stone-free state after RIRS.

Conclusions

Performing SWL before RIRS may favor stone eliminations during surgery and increase the stone-free rate in selected patients.

Presentation of a method at the Exploration Stage according to IDEAL: Percutaneous nephrolithotomy (PCNL) under local infiltrative anesthesia is a feasible and effective method - retrospective analysis of 439 patients

INTRODUCTION

This study addresses minimally invasive anesthesiologic and analgetic approaches for stone surgery in the upper urinary tract. Aim of this retrospective analysis is to compare feasibility, safety and complication rates of percutaneous nephrolithotomy (PCNL) under local infiltration anesthesia alone (Group I) and additive intravenous analgetics and/or sedative medications (Group II).

MATERIAL AND METHODS

This is a single center study. A total of 439 patients have been included from November 2003 until March 2012. A total of 226 patients were assigned to Group I receiving local infiltration anesthesia alone, whereas 213 patients were assigned to Group II receiving additive intravenous analgetics and/or sedative medications. Demographic characteristics and stone characteristics have been evaluated to determine feasibility, complication rates for safety, and stone-free rates for effectiveness. The study and the reported technique have then been retrospectively analysed according to the IDEAL stages of surgical innovation.

RESULTS

All included patients who accepted local infiltration anesthesia underwent PCNL successfully. The mean American Society of Anesthesiologists score (ASA) of the included patients was 2.15 ±0.37 (range, 1-4). PCNL was indicated in 138 patients due to pelvic calculi, in 171 patients due to renal calculi, in 66 patients due to partial staghorn, in 48 patients due to complete staghorn and in 16 patients due to upper ureteral stones. The total stone free rate in our patients was 78.4% over all stone localizations. Compared to the possibility of using additive intravenous analgetics and/or sedative medications we could show differences in the median age (p=0.005) suggesting that older patients did better tolerate the infiltration anesthesia than patients at younger ages. We did also remark not statistically significant differences in Group I and Group II as for number of tracts, operation duration, hemoglobin drop, fever, transfusion rate, and stone free rate, but not for severe complications such as perirenal hematoma, colon perforation, pleura perforation, AV fistula, skin fistula, and mortality rate.

CONCLUSION

PCNL performed under local infiltration anesthesia is a feasible method. It provides satisfactory positive clinical outcomes. Younger age seems to predispose to conversion to extended anesthesiologic procedures. When retrospectively applying the IDEAL criteria, the method can be assigned to the E level or stage 2b.

Percutaneous Nephrolithotomy with Amplatz and Alken Dilators: An Eight-Year Single Tertiary Care Centre Experience

Background

Percutaneous nephrolithotomy (PNL) is the standard procedure for patients with renal stones over 2 cm in diameter. We analyzed complications after this procedure focusing on two different methods of tract dilation.

Material/Methods

Between August 2008 and April 2016 222 percutaneous nephrolithotomies were performed in a total of 208 patients. The Group I (n=123) comprised patients where Alken dilatators were used, while Group II (n=99) comprised patients where Amplatz dilators were used. Efficacy was examined based on ultrasound and x-ray examination one month after the procedure. Complications were recorded using Clavien Dindo classification.

Results

Efficacy was 85.3% and 86.8% in group I and II, respectively (p=0.77). Grade I complications were present in 14.6% and 3%, grade II were present in 9.7% and 8%, grade IIIa were present in 2.4% and 2%, grade IIIb were present in 1.6% and 2%, grade IVa were present in 1.6% and 7%, grade IVb were present in 3.2% and 1% in Group I and Group II, respectively. These differences were statistically significant (p=0.03).

Conclusions

Efficacy was comparable between Alken dilator and Amplatz dilator groups. In group I, there were more postoperative fevers >38.5 °C and a higher rate of urosepsis. On the other hand, in group II we observed more pleural injuries. All differences resulted from the type of access to the kidney (inter/infracostal), punctured calyx, and utilization (or not) of access sheath rather than type of dilators itself.

Is it necessary to actively remove stone fragments during retrograde intrarenal surgery?

Purpose

Based on the experiences of our center, we sought to verify the necessity of actively removing stones during retrograde intrarenal surgery (RIRS) for the management of renal stones.

Materials and Methods

From March 2010 to March 2015, 248 patients underwent RIRS at our center. We classified these patients into 2 groups according to the performance of active stone removal; group A (n=172) included the patients whose stones were actively removed using a stone basket, and group B (n=76) included the patients whose stones were fragmented with laser lithotripsy without active removal of the fragments. We retrospectively compared the operation time, success rate, and complication rate between the 2 groups.

Results

There were no significant differences between groups A and B in terms of mean age (56.1 years vs. 58.6 years), male to female ratio (115:57 vs. 46:30), mean body mass index (24.5 kg/m² vs. 25.0 kg/m²), mean preoperative size of stone (11.1 mm vs. 11.1 mm), the ratio of unilateral and bilateral stones (136:36 vs. 64:12), success rate (89.0% vs. 86.8%), operation time (82.5 minutes vs. 82.1 minutes), overall complication rate (9.9% vs. 11.8%), incidence of febrile urinary tract infection (6.4% vs. 2.6%), gross hematuria (1.7% vs. 2.6%), or postoperative de novo hydronephrosis (2.9% vs. 5.3%).

Conclusions

This study demonstrated that during RIRS, fragmentation only, without the active removal of stones, is a safe and effective technique in which the surgical outcomes are comparable to those of procedures involving the active removal of stones.

Surgical Management of Stones: American Urological Association/Endourological Society Guideline, PART II

PURPOSE

This Guideline is intended to provide a clinical framework for the surgical management of patients with kidney and/or ureteral stones. The summary presented herein represents Part II of the two-part series dedicated to Surgical Management of Stones: American Urological Association/Endourological Society Guideline. Please refer to Part I for introductory information and a discussion of pre-operative imaging and special cases.

MATERIALS AND METHODS

A systematic review of the literature (search dates 1/1/1985 to 5/31/2015) was conducted to identify peer-reviewed studies relevant to the surgical management of stones. The review yielded an evidence base of 1,911 articles after application of inclusion/exclusion criteria. These publications were used to create the Guideline statements. Evidence-based statements of Strong, Moderate, or Conditional Recommendation were developed based on benefits and risks/burdens to patients. Additional directives are provided as Clinical Principles and Expert Opinions when insufficient evidence existed.

RESULTS

The Panel identified 12 adult Index Patients to represent the most common cases seen in clinical practice. Three additional Index Patients were also created to describe the more commonly encountered special cases, including pediatric and pregnant patients. With these patients in mind, Guideline statements were developed to aid the clinician in identifying optimal management.

CONCLUSIONS

Proper treatment selection, which is directed by patient- and stone-specific factors, remains the greatest predictor of successful treatment outcomes. This Guideline is intended for use in conjunction with the individual patient's treatment goals. In all cases, patient preferences and personal goals should be considered when choosing a management strategy.

Ultra-mini-percutaneous nephrolithotomy: A minimally-invasive option for percutaneous stone removal

Introduction:

Percutaneous nephrolithotomy (PCNL) has witnessed rapid advancements, the latest being ultra-mini-percutaneous nephrolithotomy (UMP), which makes the use of 11–13F sheaths as compared to 24–30F sizes used in conventional PCNL. This miniaturization aims to reduce morbidity and improve patient outcomes. We evaluated the safety and efficacy of UMP and report our ourtcomes.

Patients and Methods:

A total of 120 patients underwent UMP from July 2012 to March 2014. These patients had a single unilateral renal stone measuring between 8 and 20 mm. All patients underwent UMP using a 3F nephroscope, 7.5F inner sheath, and 11F or 13F outer metallic cannula, which served as the Amplatz sheath. Stone fragmentation and clearance were achieved with holmium laser. No nephrostomy or stent was used routinely.

Results:

Complete stone fragmentation was achieved in 114 out of 120 patients (95%) using UMP; whereas the remaining 6 were converted into mini-PCNL using a 12.5F nephroscope and 15F Amplatz sheath. The mean operative time was 39.7 ± 15.4 min, and the mean postoperative hospital stay was 22.3 ± 2.2 h. Postoperatively, 6 (5%) patients had residual fragments measuring ≤4 mm. At the 2 weeks follow-up, the stone-free status was >99% (119/120). There were no significant postoperative complications.

Conclusion:

This study shows UMP to be an effective and safe procedure for managing stones up to 20 mm. This procedure offers an attractive alternative to shock wave lithotripsy and retrograde intrarenal surgery for managing small stones.

Outcomes of ureteroscopy for patients with stones in a solitary kidney: evidence from a systematic review

INTRODUCTION

Management of urolithiasis in a solitary functioning kidney can be clinically challenging. The aim of this article was to review the outcomes of URS for patients with stone disease in a solitary kidney and critically appraise the existing evidence and outcome reporting standards.

MATERIAL AND METHODS

We conducted a systematic review in line with PRISMA checklist and Cochrane guidelines between January 1980 and February 2015. Our inclusion criteria were all English language articles reporting on a minimum of 10 patients with a solitary kidney undergoing ureteroscopy for stone disease.

RESULTS

A total of 116 patients (mean age 50 years) underwent URS for stones in solitary kidney. For a mean stone size of 16.8 mm (range: 5-60 mm) and 1.23 procedures/patient, the mean stone free rate was 87%. No significant change in renal function was recorded in any of the studies although a transient elevation in creatinine was reported in 10 (8.6%) patients. A total of 33 (28%) complications were recorded a majority (n = 21) of which were Clavien grade I. The Clavien grade II/III complications as reported by authors were urosepsis, steinstrasse and renal colic. None of the procedures required conversion to open surgery with no cases of renal haematoma or ureteric perforation.

CONCLUSIONS

This contemporary review highlights URS as a viable treatment option for stone disease in patients with a solitary kidney. It is associated with superior clearance rates to SWL and fewer high-risk complications compared to PCNL.

Which factors affect the hospital re-admission and re-hospitalization after flexible ureterorenoscopy for kidney stone?

PURPOSE

To investigate patient- and procedure-related factors associated with hospital re-admission (HR) and re-hospitalization following flexible ureteroscopy (f-URS).

PATIENTS AND METHODS

The records of patients who underwent f-URS for renal stones in two reference centers between 2011 and 2015 were examined retrospectively. Patients who were re-admitted to the hospital or re-hospitalized for any reason within 30 days after hospital discharge related to the f-URS procedure were evaluated. The patient- and procedure-related factors affecting the re-admission and re-hospitalization rates were revealed using backward stepwise multiple binary logistic regression analysis.

RESULTS

The study included 647 patients with a mean age of 46.1 ± 13.7 years. The mean BMI was 27.3 ± 4.6 kg/m(2), and the median ASA score was 1.85. The mean stone diameter was 14.2 ± 5.3 mm. The mean operation and fluoroscopy times were 50.2 ± 16.9 min and 43.1 ± 37.6 s, respectively. The mean hospitalization time was 1.42 ± 0.84 days, and the complication rate was 12.8 % (83/647). Overall, 523 (80.3 %) patients became stone-free, while residual fragments <4 mm were detected in 73 (11.3 %) patients. The procedure failed in 7.9 % of the cases. While 82 (12.7 %) patients were re-admitted, 31 (4.8 %) patients were re-hospitalized for further treatment. Stone-free status was an independent predictor of HR, while the stone-free status, hospitalization time, and postoperative complications all predicted re-hospitalization.

CONCLUSIONS

We found that inability to achieve stone-free status predicted HR and re-hospitalization, while postoperative complication and prolonged hospitalization also predicted re-hospitalization.

Comparing the Efficacy of a Multimodular Flexible Ureteroscope With Its Conventional Counterpart in the Management of Renal Stones

OBJECTIVE

To report our prospective comparison of clinical efficacy between multimodular flexible ureteroscope, PolyScope, and conventional flexible ureteroscope, both combined with holmium laser lithotripsy in managing renal stones <3 cm in diameter.

PATIENTS AND METHODS

Between February 2011 and July 2014, a total of 360 adult patients with renal stones were randomized in a single tertiary-care center trial. For 180 patients in each arm, flexible ureteroscopy and holmium laser lithotripsy were done with either PolyScope or Olympus URF P-5 as control. The primary end points were single-session stone fragmentation rate and stone-free rate. The secondary end points comprised operation time, complication rate, and hospital stay.

RESULTS

Demographic and preoperative parameters were comparable between 2 groups. For stones of different locations and sizes, single-session stone fragmentation rate of PolyScope was similar to that of URF P-5. However, for lower calyceal stones, URF P-5 was significantly better than PolyScope (82.0% vs 69.2%; P = .022). No statistically significant difference existed in single-session or overall stone-free rate, complication rate, and hospital stay. Mean operation time of PolyScope group was 92.6 ± 20.2 minutes, 9 minutes (10.8%) longer than that of URF P-5 group 83.3 ± 17.1 minutes (P < .01).

CONCLUSION

PolyScope demonstrates similar overall stone clearance rate to a conventional flexible ureteroscope in managing renal calculi <3 cm in diameter, but for lower pole stones, it is of inferior efficacy and it is more skillfully demanding, taking longer operation time.

Retrograde intrarenal surgery versus percutaneous lithotripsy to treat renal stones 2-3 cm in diameter

Objective. Retrograde intrarenal surgery (RIRS) performed using a flexible ureterorenoscope marked the beginning of a new era in urology. Today, even staghorn stones are successfully treated via RIRS. The recommended treatment for larger stones is percutaneous nephrolithotomy (PNL). However, the question of whether PNL or RIRS should be the first-line treatment option for larger stones remains controversial. In this study, we contribute to the debate by comparing the success and complication rates of PNL and RIRS that were used to treat renal pelvis stones 2-3 cm in diameter. Materials and Methods. The medical records of 154 patients (74 PNL, 80 RIRS) were retrospectively evaluated. PNL patients were placed in Group 1 and RIRS patients in Group 2. Results. The complete stone-free rates were 95.5% in the PNL group and 80.6% in the RIRS group 1 month postoperatively (P = 0.061). The respective complication rates (evaluated using the Clavien system) were 13.5% and 8.8% (P = 0.520). Conclusions. RIRS affords a comparable success rate, causes fewer complications than PNL, and seems to be a promising alternative to PNL when larger stones are to be treated. Prospective randomized controlled trials are needed to confirm these findings.

Comparison of flexible ureterorenoscopy and micropercutaneous nephrolithotomy in the treatment for moderately size lower-pole stones

PURPOSE

To present a retrospective comparative clinical study of micropercutaneous nephrolithotomy (microperc) versus flexible ureterorenoscopy (F-URS) in treatment of moderate-size lower-pole stones (LPSs).

METHODS

We retrospectively reviewed data on patients with isolated LPSs ≤2 cm in diameter treated with F-URS and/or microperc in two referral centers. Patients were divided into two groups by treatment modality: F-URS (Group 1) and microperc (Group 2). Demographics and perioperative parameters were analyzed.

RESULTS

A total of 127 patients with isolated LPSs were treated via F-URS (Group 1, n = 59) and microperc (Group 2, n = 68). Mean patient age in microperc group was slightly lower than in F-URS group (p = 0.112). We found no statistically significant difference in terms of either the size or number of stones in two groups (p = 0.113 and p = 0.209, respectively). Operative time was shorter in microperc, whereas fluoroscopy time was shorter in F-URS (60.1 ± 26.2 vs. 46.2 ± 24.3 min, p < 0.001; and 28.3 ± 19.1 vs. 108.9 ± 65.2 s, p < 0.001). Mean fall in hemoglobin level was statistically significantly lower in F-URS and hospitalization time was also significantly shorter in F-URS (0.68 ± 0.51 vs. 1.29 ± 0.88 mg/dL, p < 0.001; and 23.0 ± 58.1 vs. 33.8 ± 17.2 h, p < 0.001, respectively). Stone-free rates (SFRs) were 74.5 % (44/59) in Group 1 and 88.2 % (60/68) in Group 2 (p < 0.001).

CONCLUSIONS

We found that microperc was safe and efficacious when used to treat moderate-size LPSs and may be considered as an alternative to F-URS, affording a higher SFR. Our study supports the notion that microperc should play an increasing role in treatment of LPSs.

The cumulative analgesic consumption score (CACS): evaluation of a new score to describe postsurgical analgesic consumption as a surrogate parameter for postoperative pain and invasiveness of surgical procedures

OBJECTIVE

To validate and evaluate the applicability of a new score to describe postsurgical analgesic consumption in urological and surgical patients across different categories of pain medications and the invasiveness of medical interventions.

MATERIALS AND METHODS

The cumulative analgesic consumption score (CACS) was determined for two cohorts of patients split into three groups with surgeries involving clinically distinct levels of invasiveness (n = 2 x 60). Nonparametric statistical analyses were performed to determine differences between the CACS among the different groups and to assess the correlation between CACS and numeric rating scale (NRS) values for pain intensity.

RESULTS

The score was determined for postoperative days 1 and 2 and revealed median scores of 0 (0-11), 3 (0-22) and 10 (6-17) for UA (urological patients from group A), UB (group B) and UC (group C), respectively, and 4 (0-20), 8 (0-38) and 17 (7-68) for SA (surgical patients from group A, SB (group B) and SC (group C), respectively. CACS enabled reliable differentiation between groups involving different levels of invasiveness (p < 0.001). CACS and peak NRS values showed variable degrees of correlation, as expressed by levels of significance ranging from p < 0.001 to p = 0.34 (NS).

CONCLUSIONS

The CACS is a valid and easily applicable tool to describe postsurgical analgesic consumption in urological and surgical patients. It can be used as a surrogate parameter to assess postsurgical pain and the invasiveness of surgical procedures. These aspects may be measured to compare surgical procedures, in both clinical trials and clinical practice settings.

Extracorporeal shock wave lithotripsy (ESWL) versus percutaneous nephrolithotomy (PCNL) or retrograde intrarenal surgery (RIRS) for kidney stones

BACKGROUND

Stones in the urinary tract are a common medical problem in the general population. At present, the great expansion in minimally invasive techniques has led to the decrease in open surgery. Extracorporeal shock wave lithotripsy (ESWL) has been introduced as an alternative approach which disintegrates stones in the kidney and upper urinary tract through the use of shock waves. Nevertheless, as there are limitations with the success rate in ESWL, other minimally invasive modalities for kidney stones such as percutaneous nephrolithotomy (PCNL) and retrograde intrarenal surgery (RIRS) are also widely applied. This is an update of a review first published in 2009.

OBJECTIVES

This review aimed to assess the effectiveness and complications of ESWL for kidney stones compared with PCNL or RIRS.

SEARCH METHODS

We searched the Cochrane Renal Group's Specialised Register to 3 March 2014 through contact with the Trials' Search Co-ordinator using search terms relevant to this review.

SELECTION CRITERIA

Randomised controlled trials (RCTs) assessing the use of ESWL compared to PCNL or RIRS for kidney stone management.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed all the studies for inclusion. Statistical analyses were performed using the random effects model and the results expressed as risk ratio (RR) for dichotomous outcomes or mean difference (MD) for continuous data with 95% confidence intervals (CI).

MAIN RESULTS

Five studies (338 patients) were included, four studies compared ESWL to PCNL and one compared ESWL with RIRS. Random sequence generation was reported in three studies and unclear in two. Allocation concealment was not reported in any of the included studies. Blinding of participants and investigators could not be undertaken due to the nature of the interventions; blinding of outcome assessors was not reported. Reporting bias was judged to be low risk in all studies. One study was funded by industry and in one study the number of participants in each group was unbalanced.The success of treatment at three months was significantly greater in the PCNL compared to the ESWL group (3 studies, 201 participants: RR 0.46, 95% CI 0.35 to 0.62). Re-treatment (1 study, 122 participants: RR 1.81, 95% CI 0.66 to 4.99) and using auxiliary procedures (2 studies, 184 participants: RR 9.06, 95% CI 1.20 to 68.64) was significantly increased with ESWL group compared to PCNL. The efficiency quotient (EQ; used to assess the effectiveness of procedures) higher for PCNL than ESWL; however EQ decreased when stone size increased. Duration of treatment (MD -36.00 min, 95% CI -54.10 to -17.90) and hospital stay (1 study, 49 participants: MD -3.30 days, 95% CI -5.45 to -1.15) were significantly shorter in the ESWL group. Overall more complications were reported with PCNL, however we were unable to meta-analyse the included studies due to the differing outcomes reported and the timing of the outcome measurements.One study compared ESWL versus RIRS for lower pole kidney stones. The success of treatment was not significantly different at the end of the third month (58 participants: RR 0.91, 95% CI 0.64 to 1.30). Mean procedural time and mean hospital stay was reported to be longer in the RIRS group.

AUTHORS' CONCLUSIONS

Results from five small studies, with low methodological quality, indicated ESWL is less effective for kidney stones than PCNL but not significantly different from RIRS. Hospital stay and duration of treatment was less with ESWL. Larger RCTs with high methodological quality are required to investigate the effectiveness and complications of ESWL for kidney stones compared to PCNL if there is any technological progress in the non-invasive elimination of the residual fragments. Moreover, further research is required for the outcomes of ESWL and RIRS in lower and non-lower pole studies including PCNL versus RIRS.

Retrograde intrarenal surgery versus percutaneous nephrolithotomy for treatment of renal stones >2 cm: a meta-analysis

OBJECTIVE

To systematically review the efficacy and safety of retrograde intrarenal surgery (RIRS) versus percutaneous nephrolithotomy (PCNL) for the treatment of renal calculi >2 cm.

METHODS

We searched PubMed, Cochrane Library, Embase and the Chinese Biomedical Literature Database about RIRS and PCNL for the treatment of renal stones. The retrieval time ended in December 2013. All clinical trials were retrieved and their included references investigated. Two reviewers independently assessed the quality of all included studies, and the eligible studies were included and analyzed using the RevMan 5.2 software.

RESULTS

Two randomized controlled trials and six clinical controlled trials were included, involving a total of 590 patients. Our meta-analysis showed that there were not significant differences in stone-free rate (relative risk [RR] = 0.95, 95% confidence interval (CI) 0.88-1.02, p = 0.11) and fever (RR = 0.95, 95% CI 0.54-1.67, p = 0.85) between RIRS and PCNL. We found that hospital stay (weighted mean difference [WMD] = -2.10, 95% CI -3.08 to -1.11, p < 0.10) and bleeding (RR = 0.20, 95% CI 0.06-0.68, p = 0.01) were lower and operation time was longer (WMD = 19.11, 95% CI 7.83-30.39, p < 0.10) for RIRS.

CONCLUSION

RIRS is a safe and effective procedure. It can successfully treat patients with stones >2 cm with a high stone-free rate and significantly reduce hospital stay without increasing complications. RIRS can be used as an alternative treatment to PCNL in selected cases with larger renal stones. However, further randomized trials are needed to confirm these findings.

Kidney stones over 2 cm in diameter-between guidelines and individual approach

The prevalence of urolithiasis has been observed to increase during last decades. Kidney stones over 2 cm in diameter are the common urologic problem. European and American Associations of Urology has published guidelines on Urolithiasis and presented the most effective tools to treat large stones. On the other hand many experienced endourologic centres choose other modalities from their armamentarium. All treatment methods are characterized by their efficacy and safety which are usually inversely proportional. It is crucial for patients and physicians to find a golden mean. Percutaneous lithotripsy is still considered treatment of choice with more than 95% efficacy. Less invasive retrograde intrarenal surgery is also less effective, but burdened with lower complication rate. Extracorporeal shockwave lithotripsy is feasible in paediatric patients with acceptable stone free rates. Open surgery (pylolithotomy and anatrophic nephrolithotomy) are almost obsolete techniques. All methods have their pros and cons. Physicians should share decisions regarding treatment modalities with patients.

Percutaneous nephrolithotomy versus retrograde intrarenal surgery: a systematic review and meta-analysis

CONTEXT

Recent advances in technology have led to the implementation of mini- and micro-percutaneous nephrolithotomy (PCNL) as well as retrograde intrarenal surgery (RIRS) in the management of kidney stones.

OBJECTIVE

To provide a systematic review and meta-analysis of studies comparing RIRS with PCNL techniques for the treatment of kidney stones.

EVIDENCE ACQUISITION

A systematic literature review was performed in March 2014 using the PubMed, Scopus, and Web of Science databases to identify relevant studies. Article selection proceeded according to the search strategy based on Preferred Reporting Items for Systematic Reviews and Meta-analysis criteria. A subgroup analysis was performed comparing standard PCNL and minimally invasive percutaneous procedures (MIPPs) including mini-PCNL and micro-PCNL with RIRS, separately.

EVIDENCE SYNTHESIS

Two randomised and eight nonrandomised studies were analysed. PCNL techniques provided a significantly higher stone-free rate (weighted mean difference [WMD]: 2.19; 95% confidence interval [CI], 1.53-3.13; p<0.00001) but also higher complication rates (odds ratio [OR]: 1.61; 95% CI, 1.11-2.35; p<0.01) and a larger postoperative decrease in haemoglobin levels (WMD: 0.87; 95% CI, 0.51-1.22; p<0.00001). In contrast, RIRS led to a shorter hospital stay (WMD: 1.28; 95% CI, 0.79-1.77; p<0.0001). At subgroup analysis, RIRS provided a significantly higher stone-free rate than MIPPs (WMD: 1.70; 95% CI, 1.07-2.70; p=0.03) but less than standard PCNL (OR: 4.32; 95% CI, 1.99-9.37; p=0.0002). Hospital stay was shorter for RIRS compared with both MIPPs (WMD: 1.11; 95% CI, 0.39-1.83; p=0.003) and standard PCNL (WMD: 1.84 d; 95% CI, 0.64-3.04; p=0.003).

CONCLUSIONS

PCNL is associated with higher stone-free rates at the expense of higher complication rates, blood loss, and admission times. Standard PCNL offers stone-free rates superior to those of RIRS, whereas RIRS provides higher stone free rates than MIPPs. Given the added morbidity and lower efficacy of MIPPs, RIRS should be considered standard therapy for stones <2 cm until appropriate randomised studies are performed. When flexible instruments are not available, standard PCNL should be considered due to the lower efficacy of MIPPs.

PATIENT SUMMARY

We searched the literature for studies comparing new minimally invasive techniques for the treatment of kidney stones. The analysis of 10 available studies shows that treatment can be tailored to the patient by balancing the advantages and disadvantages of each technique.

Is retrograde intrarenal surgery a viable treatment option for renal stones in patients with solitary kidney?

PURPOSE

To evaluate the effectiveness and safety of retrograde intrarenal surgery (RIRS) for stones up to 2 cm in diameter in patients with solitary kidney.

METHODS

From January 2008 to January 2013, we prospectively enrolled all consecutive patients with solitary kidney and renal stones. Plain abdominal computed tomography scan was performed preoperatively and 1 month after the procedure to assess the stone-free rates (SFR). Serum creatinine levels were detected preoperatively, at day 1 postoperatively, at 1 month postoperatively, and then every 6 months postoperatively.

RESULTS

During the study period, we prospectively enrolled a total of 29 patients. The mean age was 55.7 ± 12.3 years; the mean stone size was 1.3 ± 0.4 cm. The primary SFR was 72.4 %; the secondary SFR was 93.1 %. The mean number of procedures per patient was 1.24. The mean serum creatinine levels were 1.5 ± 0.6, 1.6 ± 0.7, 1.6 ± 0.6, and 1.7 ± 0.7 mg/dl preoperatively, at 1 day after RIRS, at 1 month after RIRS, and at 1 year after RIRS, respectively, without detection of any statistical difference (p = 0.76). Median follow-up time was 35.7 ± 19.3 (12-72) months, but that was available for only 18 patients. The mean serum creatinine level at the last follow-up was 1.7 ± 0.9 mg/dl. No major complications were recorded. Grade I complications occurred in eight patients (27.4 %).

CONCLUSIONS

RIRS is safe and effective in the treatment of renal stones in patients with solitary kidney, without worsening renal function.

Cumulative sum analysis for experiences of a single-session retrograde intrarenal stone surgery and analysis of predictors for stone-free status

INTRODUCTION

This study investigated the learning curve of a single-session retrograde intrarenal surgery (RIRS) in patients with mid-sized stones. Competence and trainee proficiency for RIRS was assessed using cumulative sum analysis (CUSUM).

MATERIALS AND METHODS

The study design and the use of patients' information stored in the hospital database were approved by the Institutional Review Board of our institution. A retrospective review was performed for 100 patients who underwent a single-session RIRS. Patients were included if the main stone had a maximal diameter between 10 and 30 mm. The presence of a residual stone was checked on postoperative day 1 and at one-month follow-up visit. Fragmentation efficacy was calculated "removed stone volume (mm(3)) divided by operative time (min)". CUSUM analysis was used for monitoring change in fragmentation efficacy, and we tested whether or not acceptable surgical outcomes were achieved.

RESULTS

The mean age was 54.7±14.8 years. Serum creatinine level did not change significantly. Estimated GFR and hemoglobin were within normal limits postoperatively. The CUSUM curve tended to be flat until the 25th case and showed a rising pattern but declined again until the 56th case. After that point, the fragmentation efficacy reached a plateau. The acceptable level of fragmentation efficacy was 25 ml/min. Multivariate logistic regression analyses showed that stone-free rate was significantly lower for cases with multiple stones than those with a single stone (OR = 0.147, CI 0.032 - 0.674, P value  = 0.005) and for cases with higher number of sites (OR = 0.676, CI 0.517 - 0.882, P value  = 0.004).

CONCLUSIONS

The statistical analysis of RIRS learning experience revealed that 56 cases were required for reaching a plateau in the learning curve. The number of stones and the number of sites were significant predictors for stone-free status.

Combination of debulking single-tract percutaneous nephrolithotomy followed by retrograde intrarenal surgery for staghorn stones in solitary kidneys

OBJECTIVE

The aim of this study was to report a therapeutic approach comprising a combination of debulking single-tract percutaneous nephrolithotomy (PCNL) and subsequent retrograde intrarenal surgery (RIRS) for treatment of staghorn stones in patients with solitary kidney.

MATERIALS AND METHODS

A retrospective review was undertaken of 56 patients with staghorn stones in a solitary kidney who underwent the above-mentioned combination therapy. PCNL was first performed for stone debulking and RIRS was then used to remove residual stones after an interval of 2-4 days. Data were collected on operative parameters, stone-free rate (SFR), complications and renal functions.

RESULTS

The staghorn stones had a mean stone burden of 2548 ± 1028 mm(2) (range 1438-3956 mm(2)). The SFR after 3 months was 89.3%. The overall blood transfusion rate was 7.1%. Complications were observed in nine patients (16.1%), including selective renal artery embolization, fever, gross haematuria and steinstrasse in one, two, three and three cases, respectively. At a mean follow-up of 31 months, available in 38 patients, kidney function was stable in 71%, improved in 26.3% and worsened in 2.7%, according to serum creatinine levels that remained within ±20%, or that increased or decreased outside this range. No patient required haemodialysis.

CONCLUSIONS

Combining single-tract PCNL with subsequent RIRS was an effective strategic option for treating staghorn stones in solitary kidneys. The method gave an excellent SFR, satisfactory preservation of renal function, reduced bleeding risk and potentially less morbidity than that associated with multiple-tract PCNL.

Percutaneous nephrolithotomy under local infiltration anesthesia: a single-center experience of 2000 Chinese cases

OBJECTIVE

To determine the feasibility and safety of percutaneous nephrolithotomy (PCNL) in treating upper urinary calculi under local infiltration anesthesia.

METHODS

A series of 2000 patients with upper urinary calculi underwent PCNL under local infiltration anesthesia. Of the 2000 patients, 536 had upper ureteral calculi, 805 patients had pelvic calculi, and 659 patients had complex renal calculi. Pethidine premedication (75-100 mg) and Phenergan (25 mg) were used half an hour preoperatively. The mean pain scores at 0, 6, 24, and 48 hours postoperatively, the demographic characteristics, and the stones characteristics were evaluated to determine the feasibility. The complications were evaluated to determine the safety, and stone-free rate was evaluated to determine effectivity.

RESULTS

The mean American Society of Anesthesiologists score was 1.55 ± 0.54 (range, 1-3). The mean operative time was 48 minutes (range, 20-125). The mean Visual Analogue Scale scores at 0, 6, 24, and 48 hours postoperatively were 3.62, 3.02, 2.27, and 2.09, respectively. The mean hemoglobin drop was 1.06 g/dL (range, 0.2-6.8). Sixty-five patients (3.3%) received transfusions, 10 patients (0.5%) required selective renal angioembolism (Clavien grade II), and 1 patient (0.05%) received chest drainage therapy (Clavien grade II). The total stone-free rate was 85.8%.

CONCLUSION

Local infiltration anesthesia is a well-tolerated alternative anesthesia technique that provides effective intraoperative and postoperative analgesia for PCNL. PCNL performed under local infiltration anesthesia in a selected group of patients is feasible and provides satisfactory clinical outcomes. Comparative studies should be performed to classify efficacy, safety, tract quantity, dilation method, and the best candidates.

In vivo porcine model for practicing retrograde intrarenal surgery

OBJECTIVES

To examine the feasibility of retrograde intrarenal surgery (RIRS) in a porcine model.

MATERIALS AND METHODS

Female pigs (n = 3) were placed in a dorsal lithotomy position under general anesthesia, and stone material was inserted into the renal pelvis of the pigs. The bladder was entered with a cystoscope, and a 0.038-inch hydrophilic guidewire was passed into the renal pelvis. Following successful placement of the guidewire, a ureteral access sheath (9.5/11.5 Fr) was placed to allow for optimal visualization. A 7.5-Fr flexible ureteroscope (Karl Storz Flex-X2) and a 200-μm laser fiber were used for lithotripsy. When basketing was deemed necessary, zero-tipped nitinol stone baskets were used. Trainees then practiced all these manipulations on the model.

RESULTS

Urologists with moderate experience in advanced endourologic surgery were trained using this model. However, there were some surgical difficulties due to the urinary system anatomy of the pig. Intravaginal location of the urethra, bladder neck location of the ureters, tight ureteric orifices, tortuous ureters, longitudinally elongated renal pelvis, narrow infundibulopelvic angle and shallow calices made the passage of the instruments and maneuverability of the flexible ureteroscope more difficult than in a human model.

CONCLUSIONS

Despite some difficulties, our porcine model was very effective, because all the trainees successfully practiced the RIRS manipulations on this model.