Ultra-mini-percutaneous nephrolithotomy (PCNL) versus standard PCNL: A randomised clinical trial

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

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

Miniaturizing the approach to upper tract renal calculi: Is smaller always better? A narrative review

Newer modalities for treating upper tract urinary stones focus on maintaining and improving outcomes, reducing complications, and optimizing patient care. This narrative review aims to outline novel miniaturized endourological innovations for managing upper tract calculi.

Post-operative pain following percutaneous nephrolithotripsy- clinical correlates

OBJECTIVES

Management of postoperative pain following percutaneous nephrolithotripsy (PCNL) is a significant goal. We sought to identify risk factors and clinical correlates of postoperative pain in order to improve perioperative management and patient satisfaction.

MATERIALS AND METHODS

A single-center, retrospective analysis, from a prospectively maintained database, of all consecutive patients who underwent PCNL for renal calculi between January 2011 and August 2018. Postoperative pain was assessed using the visual analog scale (VAS) and analgesic use. We considered VAS score above 4 as meaningful. Pain management was standardized according to patirnt reported VAS scores. Multivariable logistic regression was performed to identify risk factors and clinical correlates.

RESULTS

A total of 496 patients were analyzed. Younger age was associated with VAS above 4 on the operative day and the first postoperative following PCNL (p = 0.003 and p < 0.001, respectively). Female gender was associated with VAS above 4 in the first 2 days following the operation (p < 0.001).

CONCLUSIONS

Younger age and female gender would most likely benefit from pre-emptive improved pain management protocols following PCNL.

Ultrasound versus fluoroscopy as imaging guidance for percutaneous nephrolithotomy: A systematic review and meta-analysis

OBJECTIVES

To determine whether the outcomes of ultrasound-guided percutaneous nephrolithotomy (UG-PCNL), an alternative to traditional fluoroscopy-guided percutaneous nephrolithotomy (FG-PCNL), are comparable.

METHODS

A systematic search of PubMed, Embase, and the Cochrane Library was carried out to discover investigations comparing UG-PCNL to FG-PCNL, and accordingly, a meta-analysis of those studies was performed. The primary outcomes included the stone-free rate (SFR), overall complications based on Clavien-Dindo classification, duration of surgery, duration of patients' hospitalization, and hemoglobin (Hb) drop during the surgery. All statistical analyses and visualizations were implemented utilizing R software.

RESULTS

Nineteen studies, including eight randomized clinical trials (RCTs) and eleven observational cohorts, comprising 3016 patients (1521 UG-PCNL patients) and comparing UG-PCNL with FG-PCNL met the inclusion criteria of the current study. Considering SFR, overall complications, duration of surgery, duration of hospitalization, and Hb drop, our meta-analysis revealed no statistically significant difference between UG-PCNL and FG-PCNL patients, with p-values of 0.29, 0.47, 0.98, 0.28, and 0.42, respectively. Significant differences were discovered between UG-PCNL and FG-PCNL patients in terms of the length of time they were exposed to radiation (p-value< 0.0001). Moreover, FG-PCNL had shorter access time than UG-PCNL (p-value = 0.04).

CONCLUSION

UG-PCNL provides the advantage of requiring less radiation exposure while being just as efficient as FG-PCNL; thus, this study suggests prioritizing the use of UG-PCNL.

Antegrade Percutaneous Retrieval of Upward Migrated Double-J Stent in Very Small Size Pediatric Patients Under Ultrasonic Guide

Purpose: To evaluate the safety of antegrade percutaneous retrieval migrated ureteral stent in very small size pediatric patients with ultramini instruments under ultrasonography guide. Materials and Methods: A total number of 10 out of 115 patients who were referred to our center with upward migrated Double-J (DJ) were candidates for antegrade approach from 2017 to 2020. The pyelocalyceal system was punctured in a prone position by using an 18-gauge disposable needle with Chiba tip and visualization of the upper tract by 3.5 MHz ultrasonic guidance. Then 0.038-inch J tipped guide wire was passed through the needle and the tract was dilated up to 6F under ultrasonographic guide. The 8F access sheath was positioned over the 6F dilator. The semirigid 6F ureteroscope was introduced through the sheath and DJ was removed with a grasper. Results: The mean age was 11.4 ± 5.48 months. The mean time from the previous surgery to DJ removal procedure was 6.4 ± 0.84 weeks. The mean operation time was 11.7 ± 1.76 minutes. All the patients were discharged from the hospital within the 1st day. There were no serious complications (grade 3, 4, or 5) according to Clavien-Dindo classification. Conclusion: The antegrade retrieval of upward migrated DJ with ultramini instrument under ultrasonographic guidance in failed cases of retrograde approach is a safe and effective approach in very small size pediatric patients.

Mini Versus Standard Percutaneous Nephrolithotomy for the Management of Renal Stone Disease: Systematic Review and Meta-analysis of Randomized Controlled Trials

CONTEXT

Mini percutaneous nephrolithotomy (mPNL) involves the creation of a smaller access tract compared with standard PNL (sPNL). Smaller tract sizes could lead to decreased blood loss, pain, and need for blood transfusion. Previous studies on this topic have reported variable findings and were of poor quality.

OBJECTIVE

To compare the safety and efficacy of mPNL with those of sPNL for the management of patients with renal stone disease by conducting a systematic review and meta-analysis.

EVIDENCE ACQUISITION

Systematic literature search was performed to identify relevant randomized controlled trials (RCTs) for the review. The primary outcomes for the study were stone-free rate (SFR) and blood transfusion rate. The secondary outcomes were complication rates, fever, fall in hemoglobin, operative time, length of stay (LOS), need for auxiliary procedure, and visual analog scale (VAS) score at 24 h. We followed Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, and the study protocol was registered with PROSPERO in priori (CRD42021252444).

EVIDENCE SYNTHESIS

In this review, 16 RCTs with 3961 patients were included. SFR was comparable between the two groups (risk ratio [RR] 1.01 [0.99, 1.04], p = 0.30), whereas the need for transfusion was lower with mPNL (RR 0.54 [0.37, 0.78], p = 0.001). Fall in hemoglobin (mean difference [MD] -0.67 [-0.93, -0.41], p = 0.000) and LOS (MD -0.59 [-0.81, -0.37], p = 0.000) were shorter with mPNL. Operative time was significantly shorter with sPNL (MD 8.28 [3.96, 12.59], p = 0.000). Complications were lower with mPNL (RR 0.89 [0.79, 0.97], p = 0.01). The need for auxiliary procedures (RR 0.77 [0.58, 1.03], p = 0.08) and VAS at 24 h (MD -0.79 [-1.63, 0.05], p = 0.06) were similar in the two groups.

CONCLUSIONS

Mini PNL has similar efficacy to sPNL in terms of SFRs. However, mPNL has a superior safety profile with fewer overall complications and a reduced need for blood transfusion.

PATIENT SUMMARY

In this study, we conducted a meta-analysis comparing mini and standard percutaneous nephrolithotomy (PNL) for the management of patients with renal stone disease. We showed that mini and standard PNL are associated with similar stone-free rates. Overall complications and the need for blood transfusion were lower with mini PNL.

Comparison between standard, mini and ultra-mini percutaneous nephrolithotomy for single renal stones: a prospective study

PURPOSE

Based on the current trend of miniaturization of instruments used in percutaneous nephrolithotomy (PCNL), it is necessary to compare different PCNL modalities regarding their access sheath size used. Thus, the safety and efficacy among standard, mini and ultra-mini PCNL (s-PCNL, m-PCNL, um-PCNL) were compared.

METHODS

We performed a prospective, non-randomized trial between January 2018 and July 2020. Patients with stones classified as Guy's stone score grade I were included. The set-up for s-PCNL and m-PCNL included a 30 Fr and 22 Fr percutaneous tract, respectively. In both set-ups, an ultrasonic/ballistic lithotripter was utilized. In the case of um-PCNL, a 12 Fr percutaneous tract was established. A high-power laser was used for lithotripsy. Hemoglobin drop, complication rate, length of hospital stay (LOS), stone-free rate (SFR) and operation time were evaluated.

RESULTS

A total of 84 patients, 28 patients per method, were evaluated. Hemoglobin drop was higher in the s-PCNL group when compared to m-PCNL (p = 0.008) and um-PCNL groups (p < 0.001), while um-PCNL group had the slightest hemoglobin drop. LOS was similar between s-PCNL group and m-PCNL group, but um-PCNL group required shorter hospital stay than the other two modalities (p < 0.001). The complication and transfusion rates as well as SFR did not differ between groups. Operation time in the um-PCNL set-up was longer compared to s-PCNL (p < 0.001) and m-PCNL (p = 0.011), whereas s-PCNL and m-PCNL did not differ significantly.

CONCLUSION

m-PCNL showed less hemoglobin drop, but similar operation time and SFR when compared to s-PCNL. um-PCNL showed even less hemoglobin drop, but the operation time was longer compared to the two other modalities.

The safety and efficiency of a 1470 nm laser in obtaining tract hemostasis in tubeless percutaneous nephrolithotomy: a retrospective cross-sectional study

Objective

It is challenging to perform a tubeless percutaneous nephrolithotomy (PNL) in patients with tract bleeding. The present study was designed to study the safety and efficacy of the 1470 nm laser for hemostatic completion in tubeless PNL patients with tract bleeding.

Patients and Methods

Between January 2020 and October 2021, 120 patients were retrospectively included and divided into two groups. The hemostasis group included 60 patients receiving tubeless PNL, in which a 1470 nm laser was used to manage tract bleeding. The other group included 60 patients receiving tubeless PNL in which the hemostasis procedure was not performed, serving as the control group. The differences in the patients’ demographic characteristics, procedural information, and posttreatment outcomes between the two groups were statistically compared.

Results

The differences associated with sex, age, weight, body mass index, urine culture, stone burden, calyx of puncture, degree of hydronephrosis and comorbidities between the two groups were not statistically significant. Compared with the control group, the hemostasis group showed greatly reduced blood loss (0.61 ± 0.31 vs. 0.85 ± 0.46 g/dL) and decreased postoperative hospitalization duration (2.83 ± 0.81 vs. 4.45 ± 0.91 days). The differences in operative time, stone-free rate, Visual Analogue Score and postoperative complications between the two groups were not statistically significant. In the subgroup analysis, the obese patients and patients with moderate to severe hydronephrosis in the hemostasis group also showed a significantly less blood loss (0.51 ± 0.22 vs. 0.83 ± 0.48 g/dL; 0.54 ± 0.27 vs. 0.85 ± 0.47 g/dL, respectively) and shorter length of postoperative hospitalization (2.62 ± 0.51 vs. 4.47 ± 1.19 days; 2.97 ± 0.63 vs. 4.41 ± 0.91 days, respectively) than those in the control group.

Conclusions

Our results demonstrated that 1470 nm laser is a safe, feasible and effective method to obtain tract hemostasis in tubeless PNL.

Comparison of Ultra-Mini Percutaneous Nephrolithotomy and Retrograde Intrarenal Surgery for Renal Stones: A Systematic Review and Meta-Analysis from the KSER Update Series

Miniaturized percutaneous nephrolithotomy (PCNL) and retrograde intrarenal surgery (RIRS) for renal stones have been developed to overcome the invasive disadvantages of PCNL. We aimed to compare the therapeutic effect and safety of ultra-mini percutaneous nephrolithotomy (UMPCNL) and RIRS for renal stones using an updated systematic review and meta-analysis. We searched clinical trials comparing UMPCNL and RIRS for renal stones using the PubMed, EMBASE, Cochrane Library, and Google Scholar databases up to October 2021. Seven studies were included in the current study. The renal stone size was 10–20 mm in three studies, 10–25 mm in one study, 10–35 mm in two studies, and not specified in one study. The stone-free rate of UMPCNL was higher than that of RIRS (p = 0.02; odds ratio (OR) = 2.01; 95% confidence interval (CI) = 1.12, 3.61). The complication rate showed no significant difference between UMPCNL and RIRS (p = 0.48; OR = 1.20; 95% CI = 0.73, 1.98). Regarding the operative time, UMPCNL was shorter than RIRS (p = 0.005; weighted mean difference (WMD) = −15.63; 95% CI = −26.60, −4.67). The hospital stay of UMPCNL was longer than that of RIRS (p = 0.0004; WMD = 1.48; 95% CI = 0.66, 2.31). UMPCNL showed higher efficacy than RIRS and similar safety to RIRS. UMPCNL may be a useful therapeutic option for moderate-sized renal stones.

Pediatric Stone Surgery: What Is Hot and What Is Not

PURPOSE OF REVIEW

We aim to highlight recent advances in technology and techniques for surgical management of urinary tract calculi in pediatric patients.

RECENT FINDINGS

Percutaneous nephrolithotomy (PCNL) is classically performed in the prone position. The supine PCNL was first attempted to overcome the shortcomings of difficult airway access, patient and surgeon discomfort. The supine PCNL, and subsequent modifications, has been successfully described in the pediatric population. Classically, PCNL has also been classically concluded with obligate placement of a nephrostomy tube and bladder catheter. Recently, tubeless and totally tubeless PCNL reduces pain and duration of hospitalization with satisfactory surgical outcomes in children. Finally, we describe the use of thulium laser technology, which offers improved efficacy in stone treatment and may supplant the current dominant technologies in coming years. Recent advances in pediatric stone surgery include supine PCNL, miniaturized PCNL instrumentation, tubeless procedures, and thulium laser technology.

Efficacy and safety of 3D printing-assisted percutaneous nephrolithotomy in complex renal calculi

This study evaluated the efficacy and safety of 3D printing technology combined with percutaneous nephrolithotomy in the treatment of complex renal calculi. Ninety patients with complex renal calculi were randomly divided into a 3D printing group (45 patients) and a control group (45 patients). In the 3D printing group, a patient-specific 1:1 3D printing model was established based on the patient's thin-layer CT scanning data. A 3D printing model was used for preoperative communication between doctors and patients. Preoperative puncture training, channel design, residual stone prediction, and percutaneous nephrolithotomy were performed under the guidance of a 3D printing model and B-ultrasound. The control group was treated with the conventional B-ultrasound-guided puncture method. Results suggest that there was a statistically significant difference between the two groups (P < 0.05). The overall score of the doctor-patient communication objects in the 3D printing group was 19.32 ± 1.57 points, and in the control group, it was 14.51 ± 2.13 points. The operation time of the 3D printing group was 103.21 ± 13.49 min, and that of the control group was 126.12 ± 25.87 min. The calculi clearance rate of the 3D printing group was 96%, while that of the control group was 80%. The incidence of postoperative complications was 6.67% in the 3D printing group and 22.22% in the control group. Compared with traditional percutaneous nephrolithotomy, 3D printing technology combined with percutaneous nephrolithotomy can significantly enhance the effectiveness of doctor–patient communication, shorten operation time, reduce operation bleeding, improve the stone clearance rate, reduce the incidence of complications and shorten the length of hospital stay. The proposed method is thus a safe and effective method to treat complex renal calculi.

Mini Percutaneous Kidney Stone Removal: Applicable Technologies

Percutaneous nephrolithotomy (PCNL) remains the treatment of choice for large and complex renal stones. The technological advances over the past several decades gave birth to different varieties of minimally invasive PCNLs, including the mini-PCNL, ultra-mini PCNL, super mini-PCNL, and micro-PCNL, with indications being extended to stones even larger than 20 mm. This article provides an update of all these available techniques of miniaturized PCNL along with its anatomic and physiologic impact. This should assist urologists in providing a personalized approach to the patient based on various patient- and stone-related factors to provide the best of all available technology for treatment.

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.

Opioid-sparing analgesic effects of peripheral nerve blocks in percutaneous nephrolithotomy: a systematic review

INTRODUCTION

Multimodal analgesia regimens incorporating peripheral nerve blocks (PNB) have demonstrated reduced postoperative pain, opioid use, and recovery time in various disease states. However, this remains a subject of limited investigation in the percutaneous nephrolithotomy (PCNL) domain. In the face of an ongoing opioid epidemic and collective push to enhance prescribing stewardship, we sought to examine the potential opioid-sparing effect of PNB in PCNL.

METHODS

A systematic review of Embase and PubMed was performed to identify all randomized controlled trials evaluating the use of a PNB with general anesthesia (GA) versus GA alone for pain control following PCNL. Studies evaluating neuraxial (epidural and spinal) anesthesia and those without GA as the control arm were excluded.

RESULTS

Seventeen trials evaluating 1012 procedures were included. Five different blocks were identified and evaluated: paravertebral (n=8), intercostal nerve (n=3), quadratus lumborum (n=2), transversus abdominis plane (n=1), and erector spinae (n=3). 9/16 (56%) studies observed lower pain scores with PNB use throughout the 24-hour postop period. By comparison, improved pain scores with PNB were limited to the early (<6 hours) recovery period in 5 studies and 2 found no difference. Total analgesia and opioid requirements were significantly higher in the GA control arm in nearly all studies (12/14, 86%). Operative times were similar and there were no differences in rates of intercostal access or nephrostomy tube insertion between study arms in any trial.

CONCLUSION

While greater analgesic use with GA alone likely minimizes or obscures differences in patient-reported pain scores, PNB may offer a significant opioid-sparing analgesic effect during postoperative recovery after PCNL.

Minimal invasive percutaneous nephrolithotomy (Mini-PCNL) in children: Ultrasound versus fluoroscopic guidance

BACKGROUND

Miniaturization of endoscopic instruments in percutaneous nephrolithotomy (PCNL) allowed less invasive procedures with low complication rates, especially in children. This study was conducted to evaluate the safety and efficacy of ultrasonography-guided (USG) versus fluoroscopy-guided (FG) mini-PCNL in children.

MATERIALS AND METHODS

This is a retrospective comparative study conducted from June 2015 to June 2020. The sample included 70 children (35 pateints underwent USG mini-PCNL and 35 pateints underwent FG mini-PCNL). They were compared mainly by the patients' demographic characteristics, procedural information, and post-treatment outcomes. In the USG mini-PCNL group, puncturing was performed using a 3.5 MHz US probe, whereas fluoroscopy was utilized in the FG mini- PCNL group.

RESULTS

Both groups were comparable in terms of gender, previous history of failed ESWL, and hydronephrosis grade. The mean stone burden was 15.94 ± 3.69 mm and 19.20 ± 7.41 mm in USG and FG groups, respectively (p = 0.024). The stonefree rate (SFR) was 97.1% in the USG group and 94.3% in the FG group, which was not statistically significant (p = 0.16). Mean operative time in the USG group and FG group was 69.00 ± 13.33 minutes and 63.48 ± 16.90 minutes, respectively. Four (11.4%) patients in the FG group required blood transfusions to restore the hemodynamic state (p = 0.039). Fever was detected in 4 (11.4%) patients in the USG group and 15 (31.4%) patients in the FG group (p = 0.041).

CONCLUSIONS

In children, mini PCNL under USG is safe and as effective as fluoroscopy.

Precision Stone Surgery: Current Status of Miniaturized Percutaneous Nephrolithotomy

PURPOSE OF REVIEW

Innovations in lasers and surgical technology have led to a renewed interest in the miniaturization of percutaneous nephrolithotomy (PCNL). We review the different approaches and evidence on the efficacy of mini-PCNL.

RECENT FINDINGS

Mini-PCNL encompasses a range of techniques using tract sizes from 4.8 to 22 F to treat renal stones. The most common device uses irrigation to passively extract stones out of the sheath. Super-mini-PCNL incorporates active suction. Ultra- and micro-techniques reduce the tract to smaller diameters. Laser fragmentation is the main lithotripsy modality. Studies demonstrate an association with reduced complications, hospital stay, and increased tubeless rate. Drawbacks include longer operative times while stone-free rates for larger stones may be sub-optimal. Mini-PCNL has advantages of less trauma and the avoidance of nephrostomy tubes. Ambulatory surgery is feasible in select patients. Advances in laser lithotripsy and active suction have the potential to improve stone clearance and treat larger stones.

A systematic review and meta-analysis of minimally invasive vs. standard percutaneous nephrolithotomy in the surgical management of renal stones

The present study aimed to assess current evidence on the effectiveness and safety of minimally invasive vs. standard percutaneous nephrolithotomy (PCNL) in the management of renal stones. A systematic search of electronic databases, which included PubMed, EMBASE and the Cochrane Library up to May 2019 was performed. Using Review Manager statistical software (version 5.3), primary outcomes, including stone-free rates (SFRs), were evaluated. Meanwhile, analysis was also performed to compare secondary outcomes, such as peri- and postoperative complications and operative data. Fourteen studies involving 1,611 patients with renal stones were analyzed based on the inclusion criteria. On the basis of the present analysis, mini percutaneous nephrolithotomy (MPCNL) was proven to have non-inferior clinical efficacy with respect to the SFR compared with PCNL [odds ratio (OR)=1.10; 95% confidence interval (CI), 0.84-1.44; P=0.48]. In addition, the meta-analysis showed that MPCNL had a significantly lower hemoglobin decrease [mean difference (MD)=-0.68; 95% CI, -1.05 to -0.31; P=0.0003] and fewer blood transfusions (OR=0.36; 95% CI, 0.18-0.71; P=0.003) compared with PCNL. Moreover, the MPCNL group had a shorter inpatient stay (MD=-0.81; 95% CI, -1.55 to -0.08; P=0.03) compared with the PCNL group. However, the overall evidence was insufficient to suggest a statistically significant difference in the adverse event profile for MPCNL compared with PCNL. The present meta-analysis indicates that MPCNL is an effective method for treating renal stones. Compared with PCNL, MPCNL not only has similarly high SFRs but is also associated with less blood loss, fewer blood transfusions, more favorable recovery time and shorter inpatient stays. However, the findings of the present study should be further confirmed by well-designed prospective randomized controlled trials with a larger patient series.

Classification and standardized reporting of percutaneous nephrolithotomy (PCNL): International Alliance of Urolithiasis (IAU) Consensus Statements

BACKGROUND

The aim of this study was to reach a consensus in the classification and standardized reporting for the different types of PCNLs.

METHODS

The RAND/UCLA appropriateness methodology was used to reach a consensus. Thirty-two statements were formulated reviewing the literature on guidelines and consensus on PCNLs, and included procedure specific details, outcome measurements and a classification for PCNLs. Experts were invited to two rounds of input, the first enabled independent modifications of the proposed statements and provided the option to add statements. The second round facilitated scoring of all statements. Each statement was discussed in the third round to decide which statements to include. Any suggestion or disagreement was debated and discussed to reach a consensual agreement.

RESULTS

Twenty-five recommendations were identified to provide standardized reporting of procedure and outcomes. Consensual scoring above 80% were strongly agreed upon by the panel. The top treatment related outcomes were size of sheath used (99.1%) and position for PCNL (93.5%). The highest ranked Outcome Measures included definition of postoperative hospital length of stay (94.4%) and estimated blood loss (93.5%).

CONCLUSIONS

The consensus statements will be useful to clarify operative technique, in the design of clinical trials and standardized reporting, and presentation of results to compare outcomes of different types of PCNLs.

Effectiveness of Percutaneous Nephrolithotomy, Retrograde Intrarenal Surgery, and Extracorporeal Shock Wave Lithotripsy for Treatment of Renal Stones: A Systematic Review and Meta-Analysis

Background and objectives: To perform a updated systematic review and meta-analysis comparing effectiveness of percutaneous nephrolithotomy (PCNL), retrograde intrarenal surgery (RIRS), and extracorporeal shock wave lithotripsy (ESWL) for treatment of renal stones (RS). Materials and Methods: A total of 37 studies were included in this systematic review and meta-analysis about effectiveness to treat RS. Endpoints were stone-free rates (SFR), incidence of auxiliary procedure, retreatment, and complications. We also conducted a sub-analysis of ≥2 cm stones. Results: First, PCNL had the highest SFR than others regardless of stone sizes and RIRS showed a higher SFR than ESWL in <2 cm stones. Second, auxiliary procedures were higher in ESWL than others, and it did not differ between PCNL and RIRS. Finally, in <2 cm stones, the retreatment rate of ESWL was higher than others. RIRS required significantly more retreatment procedures than PCNL in ≥2 cm stones. Complication was higher in PCNL than others, but there was no statistically significant difference in complications between RIRS and PCNL in ≥2 cm stones. For ≥2 cm stones, PCNL had the highest SFR, and auxiliary procedures and retreatment rates were significantly lower than others. Conclusions: We suggest that PCNL is a safe and effective treatment, especially for large RS.

Effectiveness of Percutaneous Nephrolithotomy, Retrograde Intrarenal Surgery, and Extracorporeal Shock Wave Lithotripsy for Treatment of Renal Stones: A Systematic Review and Meta-Analysis

Background and objectives: To perform a updated systematic review and meta-analysis comparing effectiveness of percutaneous nephrolithotomy (PCNL), retrograde intrarenal surgery (RIRS), and extracorporeal shock wave lithotripsy (ESWL) for treatment of renal stones (RS). Materials and Methods: A total of 37 studies were included in this systematic review and meta-analysis about effectiveness to treat RS. Endpoints were stone-free rates (SFR), incidence of auxiliary procedure, retreatment, and complications. We also conducted a sub-analysis of ≥2 cm stones. Results: First, PCNL had the highest SFR than others regardless of stone sizes and RIRS showed a higher SFR than ESWL in <2 cm stones. Second, auxiliary procedures were higher in ESWL than others, and it did not differ between PCNL and RIRS. Finally, in <2 cm stones, the retreatment rate of ESWL was higher than others. RIRS required significantly more retreatment procedures than PCNL in ≥2 cm stones. Complication was higher in PCNL than others, but there was no statistically significant difference in complications between RIRS and PCNL in ≥2 cm stones. For ≥2 cm stones, PCNL had the highest SFR, and auxiliary procedures and retreatment rates were significantly lower than others. Conclusions: We suggest that PCNL is a safe and effective treatment, especially for large RS.

Standard versus Mini-Percutaneous Nephrolithotomy for Renal Stones: A Meta-Analysis

Objective:

To compare the standard percutaneous nephrolithotomy and mini-percutaneous nephrolithotomy in order to determine the optimal tract size for patients with renal stones.

Methods:

A systematic search of Web of Science, EMBASE, Cochrane Library, and PubMed databases was conducted for articles published through 20 August 2019, reporting on a comparison of the standard percutaneous nephrolithotomy and mini-percutaneous nephrolithotomy using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

Results:

Of 763 studies, 14 were considered for the evidence synthesis. A total of 1980 cases were included. Of these patients, 897 cases underwent standard percutaneous nephrolithotomy, and 1083 cases underwent mini-percutaneous nephrolithotomy. Stone-free rates were 87.6% (786 of 897 patients) for standard percutaneous nephrolithotomy and 87.8% (951 of 1083 patients) for mini-percutaneous nephrolithotomy ( p = 0.57). Tract sizes of 30F and 22–26F in standard percutaneous nephrolithotomy group shorten operation time compared with mini-percutaneous nephrolithotomy ( p = 0.02; p = 0.004; respectively). Leakage ( p = 0.04), bleeding ( p = 0.01), blood transfusion ( p < 0.00001), and renal pelvis perforation ( p = 0.02) were more common in standard percutaneous nephrolithotomy group than in mini-percutaneous nephrolithotomy group. Subgroup analysis showed only blood transfusion for 30F and 22–26F standard percutaneous nephrolithotomy group was more common than mini-percutaneous nephrolithotomy ( p < 0.0001, p = 0.005, respectively).

Conclusion:

Standard percutaneous nephrolithotomy was associated with higher leakage, bleeding, blood transfusion, and renal pelvis perforation, but had a shorter operation time. Tract size of 30F improved the stone-free rate compared with mini-percutaneous nephrolithotomy, but led to more complications. Tract size of 22–26F was no better than 30F or mini-percutaneous nephrolithotomy.

Minimally invasive versus standard endoscopic combined intrarenal surgery for renal stones: a retrospective pilot study analysis

PURPOSE

The effect of combining miniaturization with endoscopic combined intrarenal surgery (ECIRS) is unclear. Thus, we compared the treatment outcomes between minimally invasive ECIRS (mini-ECIRS) using 16.5 Fr percutaneous access sheath and standard ECIRS using 24 Fr access sheath for renal stones MATERIALS AND METHODS: We retrospectively analyzed consecutive patients who underwent single session mini or standard-ECIRS in the modified Valdivia position for renal stones between April 2009 and May 2016. To adjust for patient characteristics, 77 pairs were matched using preoperative parameters including age, sex, history of febrile urinary tract infection (UTI), stone surface area, number of involved calyces, and staghorn calculi.

RESULTS

The stone free rate (SFR) was similar between mini and standard ECIRS according to non-contrast computed tomography (61.1% vs. 52.0%, p = 0.388). The rate of perioperative complications exceeding grade 2 based on the Clavien-Dindo classification was similar in both groups (19.5% vs. 26.0%, p = 0.442). Severe complications exceeding grade 3 were also similar in both groups (2.6% vs. 3.9%, p > 0.99). Two cases of septic shock were noted in each group. Although there was no difference regarding bleeding-related complications (2.6% vs. 6.5%, p = 0.442), pseudoaneurysm or blood transfusion was not observed in the mini-ECIRS group. Pain visual analog scale values in the perioperative period were lower in the mini-ECIRS group (1.34 ± 1.08 vs. 1.69 ± 1.23, p = 0.062).

CONCLUSIONS

This study demonstrated that, compared to standard ECIRS, mini-ECIRS maintained SFR without increasing perioperative complications, tended to reduce postoperative pain and had a potential to reduce bleeding-related complications. This report suggests the advantages of ECIRS miniaturization for renal stones.

The efficacy and safety of miniaturized percutaneous nephrolithotomy versus standard percutaneous nephrolithotomy: A systematic review and meta-analysis of randomized controlled trials

Purpose

Our aim was to assess the efficacy and safety of miniaturized percutaneous nephrolithotomy (mPCNL) versus standard PCNL (sPCNL) to provide higher-level evidence.

Materials and Methods

Eligible randomized controlled trials were identified from electronic databases. The data analysis was performed by the Cochrane Collaboration's software RevMan 5.3.

Results

A total of 1,219 patients from 9 articles published between 2004 and 2019 were included. Compared with those who received sPCNL, patients who received mPCNL experienced a higher stone-free rate (SFR) (odds ratio [OR], 1.43; 95% confidence interval [CI], 1.03–1.99; p=0.03), lower transfusion rates (OR, 0.33; 95% CI, 0.17–0.63; p=0.0007), and lower drops in hemoglobin (mean difference [MD], −0.72; 95% CI, −1.04 to −0.40; p<0.00001), but the operative time seemed to be significantly longer (MD, 10.98; 95% CI, 3.64–18.32; p=0.003). Of note, there was no significant difference between the two groups regarding the SFR (p=0.09) for renal calculi ≥2 cm. In addition, the meta-analysis results showed no significant differences between the groups regarding urine leakage (p=0.60), postoperative fever (p=0.71), impaired ventilation (p=0.97), or total complications (p=0.29) with no heterogeneity between trials. These results remain unaffected with regard to renal calculi ≥2 cm.

Conclusions

Our findings suggested that mPCNL had a higher SFR than sPCNL and there was no significant difference between the two groups for renal stones ≥2 cm. Besides, mPCNL tended to be associated with significantly less bleeding and a lower transfusion rate, but the duration of the procedure seemed to be significantly longer.

Tract sizes in percutaneous nephrolithotomy: does miniaturization improve outcome?

PURPOSE OF REVIEW

To provide a summary of surgical outcomes in percutaneous nephrolithotomy (PCNL) according to various techniques and tract sizes.

RECENT FINDINGS

Recent literature in this field concluded that standard PCNL (sPCNL) remains the optimal treatment for stones between 1 and 2.5 cm and can be managed with tracts 14-20 F, whereas small stones less than 1.5 cm can be treated with tracts under 14 F. According to new datasets, smaller tracts can be equally effective in the treatment and might offer the possibility to reduce bleeding, length of hospital stay, postoperative pain as well as overall complication rates when compared with sPCNL. On the other hand, longer operative time as well as lower stone-free rates, which have been the main drawbacks of the miniaturized approach, have recently shown to be comparable with sPCNL.

SUMMARY

At present, tract size is a highly debatable topic in percutaneous stone therapy. New systems for miniaturized PCNL have been developed to achieve comparable stone-free rates while reducing the incidence of common complications. The adoption of these techniques demands skilled surgeons and institutional investment for the acquisition of new equipment.

Risk Factors for Urosepsis after Minimally Invasive Percutaneous Nephrolithotomy in Patients with Preoperative Urinary Tract Infection

The purpose of this study was to assess risk factors of urosepsis after minimally invasive percutaneous nephrolithotomy (MPCNL) for the treatment of upper urinary tract stones in patients with preoperative urinary tract infection (UTI) and to explore preventive measures. Between 2008 and 2016, patients with preoperative UTI who underwent MPCNL for upper urinary tract stones were retrospectively collected. Patients were divided into nonurosepsis and urosepsis groups. Perioperative outcomes of all patients were evaluated and compared between the two groups. Risk factors for post-MPCNL urosepsis were investigated using univariate and multivariate regression analysis. A total of 843 patients including 22 patients with postoperative urosepsis (urosepsis group) and 821 patients without urosepsis (nonurosepsis group) were finally included in this study. All patients with postoperative urosepsis were cured and discharged after treatment. In univariate analysis it was demonstrated that the incidence of urosepsis after MPCNL was significantly correlated with channel size (P=0.001), surgical time (P=0.003), as well as the tear of the collection system and percutaneous renal channel crossing the renal papilla (P=0.004). Moreover, multivariate analysis showed that smaller channel size (OR = 11.192, 95% CI: 2.425-51.650, P=0.002), longer surgical time (OR = 6.762, 95% CI: 1.712-17.844, P=0.008), and tear of collection system and percutaneous renal channel crossing the renal papilla (OR = 5.531, 95% CI 1.228-14.469, P=0.012) were independent risk factors for urosepsis following MPCNL in patients with preoperative UTI. In conclusion, in patients with preoperative UTI undergoing MPCNL for upper urinary tract stones, smaller channel size, prolonged operation time, as well as tear of the collection system and percutaneous renal channel crossing the renal papilla are independent risk factors for postoperative urosepsis. Therefore, it is indicated that, in clinical practice, it is of great significance to choose appropriate channel size and avoid renal injury and control surgical time to prevent the urosepsis after MPCNL in patients with preoperative UTI.

Comparison of the clinical efficacy of sonography-guided percutaneous nephrolithotomy (PCNL) under local and general anesthesia

Objective

This study aimed to compare the effect of percutaneous nephrolithotomy (PCNL) under local infiltration anesthesia (PCNL-LIA) and general anesthesia (PCNL-GA) to treat upper urinary tract calculi on clinical application values.

Methods

Patients were randomly divided into the PCNL-LIA (16 patients) and PCNL-GA (20 patients) groups. Data on safety, cost, complications, rate of residual calculi, and prognosis were compared.

Results

The mean operation time in the PCNL-LIA group was less than that in PCNL-GA group (100±7.7 versus 120±9.0 minutes). The mean length of hospital stay in the PCNL-LIA group was shorter than that in the PCNL-GA group (6.9±0.5 versus 10.5±1.2 days). The rate of patients who required blood transfusion because of blood loss during or after surgery was less in the PCNL-LIN group than in the PCNL-GA group (13% versus 40%). The intervention rate in the PCNL-GA group was higher than that in the PCNL-LIA group. Visual analogue pain scale assessment showed that the PCNL-LIA group showed slightly more pain than the PCNL-GA group.

Conclusion

PCNL-LIA is safer, faster, and more convenient, and it also provides the benefits of a lower rate of blood loss and complications, lower cost, faster recovery, and shorter hospital stay compared with PCNL-GA.

Outcomes of retrograde intrarenal surgery compared with ultra-mini percutaneous nephrolithotomy in the management of renal calculi

INTRODUCTION

To evaluate the outcomes of retrograde intrarenal surgery (RIRS) and ultra-mini percutaneous nephrolithotomy (umPCNL) in the management of renal calculi.

MATERIAL AND METHODS

Between March 2015 and January 2018, a total of 44 patients were treated with umPCNL. The outcomes of these patients were compared with 75 patients who underwent RIRS for renal calculi during the same time period.

RESULTS

Median stone size was 9 mm in the umPCNL group and 7 mm in the RIRS group. Stone-free rates after a single procedure were achieved in 85% of patients for the RIRS group and 98% for the umPCNL group. 16% of RIRS patients were left with a ureteric stent, whilst 7% of patients (n = 5) needed a second RIRS. One patient in the umPCNL group was left with a percutaneous nephrostomy; all other patients were left totally tubeless. The mean operative time was 66 minutes in the RIRS group and 55 minutes in the umPCNL group (p = 0.04). The minor complication rates for the RIRS and umPCNL groups were 17% and 15%, respectively. One patient in the RIRS group required postoperative nephrostomy insertion; there were no major complications in the umPCNL group. The median length of stay was 0 days in the RIRS group and 1 day in the umPCNL group.

CONCLUSIONS

The overall study showed that umPCNL has low complication rates and good stone-free rates, with a lower requirement for ancilliary procedures. UmPCNL is an acceptable alternative in selected patients with small- to moderate-sized renal calculi.

The Urological Association of Asia clinical guideline for urinary stone disease

The Urological Association of Asia, consisting of 25 member associations and one affiliated member since its foundation in 1990, has planned to develop Asian guidelines for all urological fields. The field of stone diseases is the third of its guideline projects. Because of the different climates, and social, economic and ethnic environments, the clinical practice for urinary stone diseases widely varies among the Asian countries. The committee members of the Urological Association of Asia on the clinical guidelines for urinary stone disease carried out a surveillance study to better understand the diversity of the treatment strategy among different regions and subsequent systematic literature review through PubMed and MEDLINE database between 1966 and 2017. Levels of evidence and grades of recommendation for each management were decided according to the relevant strategy. Each clinical question and answer were thoroughly reviewed and discussed by all committee members and their colleagues, with suggestions from expert representatives of the American Urological Association and European Association of Urology. However, we focused on the pragmatic care of patients and our own evidence throughout Asia, which included recent surgical trends, such as miniaturized percutaneous nephrolithotomy and endoscopic combined intrarenal surgery. This guideline covers all fields of stone diseases, from etiology to recurrence prevention. Here, we present a short summary of the first version of the guideline - consisting 43 clinical questions - and overview its key practical issues.

Ultrasound-guided versus fluoroscopy-guided percutaneous nephrolithotomy: a systematic review and meta-analysis

PURPOSE

To evaluate the efficacy and safety of ultrasound-guided (UG) versus fluoroscopy-guided (FG) percutaneous nephrolithotomy (PCNL).

METHODS

A systematic search of PubMed (MEDLINE), Embase, and the Cochrane Library was conducted to identify randomized controlled trials that compared UG-PCNL with FG-PCNL, and a meta-analysis of those studies was completed. The primary outcomes assessed were stone-free rate (SFR) and complication rate. Secondary outcomes assessed were the successful access-creation rate, time necessary for entrance into the target calyx, auxiliary procedure rate, transfusion rate, hemoglobin decrease after surgery, surgery duration, and hospital stay.

RESULTS

Eight studies comprising 966 patients were included in the meta-analysis. Compared with FG-PCNL, UG-PCNL had comparable stone-free rates [odds ratio (OR) 0.95; 95% confidence interval (CI) 0.67-1.35; p = 0.79] irrespective of the patient's position, and a favorable safety profile resulting in a lower complication rate (OR 0.56; 95% CI 0.36-0.86; p = 0.009). No statistical difference was found between UG and FG groups in secondary outcomes.

CONCLUSIONS

UG-PCNL is as effective as FG-PCNL and has the advantage of lower complication rates. In addition, UG-PCNL could be performed with patients in the supine position without compromising its efficacy.