Endoscopic combined intrarenal surgery for large calculi: simultaneous use of flexible ureteroscopy and mini-percutaneous nephrolithotomy overcomes the disadvantageous of percutaneous nephrolithotomy monotherapy

Efficacy of mini-endoscopic combined intrarenal surgery for pediatric kidney calculi: a single center retrospective study

Management of large pediatric kidney calculi (PKC) is challenging. This study aimed to evaluate the efficacy and safety of miniature endoscopic combined intrarenal surgery (mini-ECIRS) for PKC. We retrospectively analyzed mini-ECIRS in 16 pediatric patients undergoing kidney stone treatment between November 2014 and October 2023 to determine its safety, efficacy, and associated outcomes. The median age was 50.50 (interquartile range: 36.75, 84.75) months, and the mean stone size was 21.63 ± 11.65 mm. The stone-free rate was 81.25%. The median decrease in hemoglobin level on the day after surgery was 1.10 (0.80, 1.55), and no patient required a blood transfusion. The median number of general anesthesia procedures was 2.00 (2.00, 2.00). Postoperative complications included fever in two patients and difficulty in removing the ureteral stent in one patient. In this cohort, five patients underwent pre-stenting under general anesthesia before mini-ECIRS. Age was significantly lower in the pre-stenting group than in the non-pre-stenting (P < 0.01); however, there were no significant differences in operative time, stone-free rate, total number of general anesthesia procedures, hemoglobin loss, or postoperative hospital stay between the groups. Mini-ECIRS was found to be a safe and efficient treatment method with a high stone removal rate in pediatric patients.

What is the definition of stone dust and how does it compare with clinically insignificant residual fragments? A comprehensive review

PURPOSE

During endoscopic stone surgery, Holmium:YAG (Ho:YAG) and Thulium Fiber Laser (TFL) technologies allow to pulverize urinary stones into fine particles, ie DUST. Yet, currently there is no consensus on the exact definition of DUST. This review aimed to define stone DUST and Clinically Insignificant Residual Fragments (CIRF).

METHODS

Embase, MEDLINE (PubMed) and Cochrane databases were searched for both in vitro and in vivo articles relating to DUST and CIRF definitions, in November 2023, using keyword combinations: "dust", "stones", "urinary calculi", "urolithiasis", "residual fragments", "dusting", "fragments", "lasers" and "clinical insignificant residual fragments".

RESULTS

DUST relates to the fine pulverization of urinary stones, defined in vitro as particles spontaneously floating with a sedimentation duration ≥ 2 sec and suited for aspiration through a 3.6Fr-working channel (WC) of a flexible ureteroscope (FURS). Generally, an upper size limit of 250 µm seems to agree with the definition of DUST. Ho:YAG with and without "Moses Technology", TFL and the recent pulsed-Thulium:YAG (pTm:YAG) can produce DUST, but no perioperative technology can currently measure DUST size. The TFL and pTm:YAG achieve better dusting compared to Ho:YAG. CIRF relates to residual fragments (RF) that are not associated with imminent stone-related events: loin pain, acute renal colic, medical or interventional retreatment. CIRF size definition has decreased from older studies based on Shock Wave Lithotripsy (SWL) (≤ 4 mm) to more recent studies based on FURS (≤ 2 mm) and Percutaneous Nephrolithotomy(PCNL) (≤ 4 mm). RF ≤ 2 mm are associated with lower stone recurrence, regrowth and clinical events rates. While CIRF should be evaluated postoperatively using Non-Contrast Computed Tomography(NCCT), there is no consensus on the best diagnostic modality to assess the presence and quantity of DUST.

CONCLUSION

DUST and CIRF refer to independent entities. DUST is defined in vitro by a stone particle size criteria of 250 µm, translating clinically as particles able to be fully aspirated through a 3.6Fr-WC without blockage. CIRF relates to ≤ 2 RF on postoperative NCCT.

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

OBJECTIVES

This study aimed to investigate the influence of tract location on surgical outcomes in endoscopic combined intrarenal surgery (ECIRS), considering the location of residual stones.

METHODS

From January 2015 to December 2021, 1417 consecutive patients underwent ECIRS in three hospitals. After excluding patients with preoperative percutaneous nephrostomy, intended multi-stage procedures, those with a tract in the renal pelvis, and those with multiple tracts, 1000 patients were retrospectively analysed by comparing three groups based on tract location: group 1 (upper calyx), group 2 (middle calyx), and group 3 (lower calyx). A multivariate logistic regression model was implemented to assess whether the tract location independently affected the stone-free status.

RESULTS

Patient characteristics were significantly different among the groups in terms of age, stone laterality, presence of calyceal stones, and hydronephrosis. There were no differences in stone-free rate (SFR) among the three groups. Multivariate analysis indicated that the tract location (group 1 or 2 compared with group 3) did not significantly affect the stone-free status (odds ratio = 1.4, 0.9-1.9, p = 0.066). Surgical duration significantly varied among the groups, with the shortest time observed in group 1. Organ injury was observed exclusively in group 1 (1.13%). Residual fragments were predominantly found in the lower calyx, with the calyx associated with the tract being the second most common location.

CONCLUSIONS

Tract location does not significantly affect SFR. To improve the SFR, observation of the lower calyx and tract placement is important.

RIRS with FV-UAS vs. MPCNL for 2-3-cm upper urinary tract stones: a prospective study

To observe the efficacy and safety of retrograde intrarenal surgery (RIRS) combined with flexible vacuum-assisted ureteral access sheath (FV-UAS) and minimally invasive percutaneous nephrolithotomy (MPCNL) in patients with 2-3 cm upper urinary tract stones. A total of 160 patients with 2-3 cm upper urinary tract stones were prospectively randomized into 2 groups-80 in the FV-UAS group and 80 cases as control in the MPCNL group. The stone-free rates (SFRs) at different times (postoperative 1st day and 4th week) were considered as the primary outcome of the study. The secondary end points were operative time, hemoglobin decrease, postoperative hospital stay, and operation-related complications. There was no obvious difference between the two groups in patient's demographics and preoperative clinical characteristics (all P > 0.05). Postoperative data showed that mean decrease in hemoglobin level was less in FV-UAS group than that in MPCNL group (5.3 vs. 10.8 g/L, P < 0.001). Postoperative hospital stay in FV-UAS group was more shorten than that in MPCNL group (2.7 vs. 4.9 days, P < 0.001). There was no statistical significance between the two groups in SFRs during postoperative 1st day and 4th week (both P > 0.05). However, in terms of the rates of bleeding and pain, MPCNL group were both significantly higher than FV-UAS group (6.2 vs. 0.0%, P = 0.023; 16.2 vs. 2.5%, P = 0.003; respectively). Our study showed that RIRS with FV-UAS, a new partnership to treat 2-3 cm upper urinary tract stones, was satisfying as it achieved a high SFR rate and a low rate of complications. This method was safe and reproducible in clinical practice.

Nonpapillary Prone Endoscopic Combined Intrarenal Surgery (ECIRS): Five-Year Experience and Outcomes from a High-Volume Center

Endoscopic combined intrarenal surgery (ECIRS) provides simultaneous retrograde and percutaneous access to the upper urinary tract. The purpose of this study is to present revised data, tips and tricks, and technique modifications arising from our five-year experience with ECIRS. The data of 62 patients who underwent nonpapillary prone ECIRS from January 2019 to November 2023 were prospectively collected. All cases were performed in the prone position. Inclusion criteria were complex stone cases with stones in multiple calyces requiring either multiple accesses or multiple sessions to achieve stone-free status. Patients' mean age was 54.4 ± 12.39 years, while the mean stone size was 39.03 ± 13.93 mm. The mean operative time was 51.23 ± 17.75 min. Primary and final stone-free rates were 83.8% and 90.3%, respectively. In total, nine patients presented with postoperative complications, which were all Grade II ones. The holmium-YAG laser type during retrograde lithotripsy was associated with significantly shorter operative times compared to the thulium fiber laser. Nonpapillary prone ECIRS is a feasible, safe, and efficient approach for patients with specific stone and anatomy characteristics. The implementation of more, higher-evidence studies is of utmost importance so that safer conclusions can be drawn.

Models to predict the surgical outcome of mini-ECIRS (endoscopic combined intrarenal surgery) for renal and/or ureteral stones

To establish a safer and more efficient treatment strategy with mini-endoscopic combined intrarenal surgery (ECIRS), the present study aimed to develop models to predict the outcomes of mini-ECIRS in patients with renal and/or ureteral stones. We retrospectively analysed consecutive patients with renal and/or ureteral stones who underwent mini-ECIRS at three Japanese tertiary institutions. Final treatment outcome was evaluated by CT imaging at 1 month postoperatively and stone free (SF) was defined as completely no residual stone or residual stone fragments ≤ 2 mm. Three prognostic models (multiple logistic regression, classification tree analysis, and machine learning-based random forest) were developed to predict surgical outcomes using preoperative clinical factors. Clinical data from 1432 ECIRS were pooled from a database registered at three institutions, and 996 single sessions of mini-ECIRS were analysed in this study. The overall SF rate was 62.3%. The multiple logistic regression model consisted of stone burden (P < 0.001), number of involved calyces (P < 0.001), nephrostomy prior to mini-ECIRS (P = 0.091), and ECOG-PS (P = 0.110), wherein the area under the curve (AUC) was 70.7%. The classification tree analysis consisted of the number of involved calyces with an AUC of 61.7%. The random forest model showed that the top predictive variable was the number of calyces involved, with an AUC of 91.9%. Internal validation revealed that the AUCs for the multiple logistic regression model, classification tree analysis and random forest models were 70.4, 69.6 and 85.9%, respectively. The number of involved calyces, and a smaller stone burden implied a SF outcome. The machine learning-based model showed remarkably high accuracy and may be a promising tool for physicians and patients to obtain proper consent, avoid inefficient surgery, and decide preoperatively on the most efficient treatment strategies, including staged mini-ECIRS.

A new training model using the self-healing properties of supramolecular hydrogels for endoscopic combined intrarenal surgery

The combination of hydronephrosis formation, ureteroscopic imaging, and ultrasound delineation has not been included in any non-biological training model of percutaneous nephrolithotomy or endoscopic combined intrarenal surgery. We aimed to develop a realistic kidney phantom using the self-healing properties of supramolecular hydrogels for percutaneous nephrolithotomy and endoscopic combined intrarenal surgery and evaluate its suitability as a training model.Expert and resident urologists performed ultrasound-guided renal pelvic punctures and flexible ureteroscopies for endoscopic combined intrarenal surgery using a training model. Subsequently, the training model was evaluated using a 17-item Likert scale questionnaire (range, 1-5 points). After being filled with carrageenan, the collecting system was inflated, and the relationship between the collecting system volume and collecting system pressure was determined. The durability of the model was verified by repeatedly inserting a 16-Fr access sheath. Five novices and seven urology experts performed the procedure. The mean questionnaire score was 4.25 (standard deviation, 0.37). The model was able to hold 50 mL of air, and the pressure in the collecting system ranged from 6 to 33 mmHg. Repeated punctures were possible even when a 16-Fr access sheath was inserted. Our new training model included the self-healing properties of supramolecular hydrogels, which are tough and flexible and can be evaluated using ultrasonography. According to the questionnaire score, the model was highly satisfactory and has potential as a new educational tool.

The Consecutive 200 Cases of Endoscopic-Combined Intrarenal Surgery: Comparison between Standard and Miniature Surgeries

Background and Objectives: Percutaneous nephrolithotomy (PCNL) is still the gold-standard treatment for large and/or complex renal stones. Endoscopic combined intrarenal surgery (ECIRS) was developed with the goal of minimizing the number of access tracts of PCNL while simultaneously improving the one-step stone-free rate (SFR). The aim of this study was to share the experience of the consecutive 200 cases of ECIRS in one institute and analyze surgical outcomes of mini-ECIRS and standard ECIRS. Materials and Methods: We performed ECIRS for 200 adult patients between July 2017 and January 2020. An ECIRS was performed with the patient under general anesthesia in the intermediate-supine position. Surgeries were finished using a tubeless technique with a simple ureteral stent insertion. Results: There were significant differences in the mean maximal stone length (MSL), the variation coefficient of stone density (VCSD), the linear calculus density (LCD), the Seoul National University Renal Stone Complexity (S-ReSC), and the modified S-ReSC scores in stone characteristics, and estimated blood loss (EBL) and operation time in peri-operative outcomes between conventional and mini-ECIRS. After propensity-score matching, there was only a difference in EBL between the two groups. In logistic regression models, MSL [odds ratio (OR) 0.953; 95% confidence interval (CI) 0.926-0.979; p < 0.001], LCD (OR 4.702; 95% CI 1.613-18.655; p = 0.013) were significant factors for the success rate after ECIRS. Conclusions: In patients who underwent a mini-ECIRS, the stones were relatively smaller and less complex, and the operation time was shorter. However, if the size of stones was similar, there was no difference in the success rate, but EBL was lower in mini-ECIRS than in standard surgery.

2022 Recommendations of the AFU Lithiasis Committee: Combined approach for the management of kidney and ureteral stones (Endoscopic Combined IntraRenal Surgery, ECIRS)

The primary objective of the combined approach is to limit the number of percutaneous access tracts for the treatment of staghorn, or complex kidney stones by simultaneous percutaneous antegrade and retrograde ureteroscopy. The other indication is the simultaneous presence of several kidney and ureteral stones or of an impacted pelvic stone. The combination of the two techniques may increase the stone-free rate and decrease the retreatment rate of complex stones compared with percutaneous nephrolithotomy alone. The patient is usually in the modified supine position. METHODOLOGY: These recommendations were developed using two methods: the Clinical Practice Recommendation (CPR) method and the ADAPTE method, depending on whether the question was considered in the European Association of Urology (EAU) recommendations (https://uroweb.org/guidelines/urolithiasis) [EAU Guidelines on urolithiasis. 2022] and their adaptability to the French context.

Needle-perc-assisted endoscopic surgery (NAES) for patients with complicated solitary kidney stones: a prospective randomized study from a single center

PURPOSE

The goal of this study is to compare traditional percutaneous nephrolithotomy (PCNL) and needle-perc-assisted endoscopic surgery (NAES) in the treatment of complicated solitary kidney stones via a single-center randomized controlled prospective study.

METHODS

A total of patients with complex (Guy's score II-IV) solitary kidney stones between July 2019 to June 2022 were enrolled in the study. Participants were stratified into two groups: needle-perc-assisted endoscopic surgery group (group A) and traditional PCNL group (group B). All procedures were finished by X-ray free technique. The clinical characteristics and outcomes were analyzed.

RESULTS

A total of 90 (44 in Group A and 46 in Group B) patients were finally included in our study. There were no statistically differences in terms of gender, age, body mass index (BMI), stone burden between two groups. The mean operative duration of Group A was significant higher than group B (95.1 ± 21.4 min vs 72.5 ± 29.5 min, p=0.02). The 1-month stone-free rate (SFR) was significant higher in Group A than B (90.9% vs 73.9%, p=0.03). A less hemoglobin drop (p=0.01), shorter postoperative in-hospital day (p=0.04), and lower severe complication (Clavien-Dindo III and above) rates (p=0.03) were observed in Group A.

CONCLUSION

For patients with solitary kidney stones, NAES technique provides a higher one-session SFR, a better renal function recovery and compared with traditional PCNL.

Initial Experience of Simultaneous Combined use of Percutaneous Nephrolithotomy and Flexible Ureteroscopy in Complex Renal Calculi: A Novel Surgical Technique of 'Through-Through' Approach

BACKGROUND

For complex branched renal calculi, the endoscopic combined intrarenal surgery (ECIRS) is worldwide prevalent. This study aimed to present a novel surgical technique of percutaneous nephrolithotomy combined with antegrade flexible ureteroscopy which is named 'Through-through' approach.

METHODS

We retrospectively analyzed the data of 68 patients with complex renal calculi who underwent combined PNL and flexible ureteroscopy surgery using 'Through-through' approach at our center between August 2019 and December 2021. The 'Through-through' approach to surgery was indicated in residual calyceal calculi that neither rigid nephroscope nor retrograde flexible ureteroscope could reach. The brief procedure of this technique involved determining the direction of targeted calyces with the nephroscope first, followed by putting flexible ureteroscope into the targeted calyx through the nephroscope instrument channel and basketing or dusting residual calculi through the flexible ureteroscope instrument channel.

RESULTS

The mean maximum stone diameter was 4.0 ± 0.4 cm. The mean operative duration was 100.1 ± 18.0 minutes, and mean hemoglobin loss was 21.4 ± 5.1 g/L. In all 68 patients, calculi were cleared in 62 patients, and the stone free rate was 91.2%. Five patients underwent further surgery after 2 weeks because of significant residual calculi. One patient that had a 6 mm residual stone chose observational follow-up. Ten patients emerged with postoperative fever but did not progress to uroseptic shock. There were no Clavien grade ≥ III complications, and none of the patients required blood transfusion.

CONCLUSION

The 'Through-through' approach is safe, feasible and effective for complex renal calculi patients. It is a complementary solution to the failed endoscopic combined intrarenal surgery.

Evolution and current applications of endoscopic combined intrarenal surgery: a scoping review from back to the future

PURPOSE OF REVIEW

To systematically review the evolution of techniques, technology, clinical utility, limitations and possible future applications of endoscopic combined intrarenal surgery (ECIRS) for ureteral and kidney stones.

RECENT FINDINGS

The literature search was performed on 18th January 2023 using PubMed, EMBASE and Scopus. 35 studies were included. Among them, six were reviews. Since its introduction in 2008, ECIRS has evolved and improved. ECIRS can be performed in different patient position, such as modified supine Valdivia position by Galdakao, prone position with split-leg and supine position with good outcomes. Instrument miniaturization has also been introduced in ECIRS making it doable in an ambulatory setting. ECIRS showed shorter operative time, lower complication rate, and retreatment compared with conventional PCNL. Operative outcomes of mini-ECIRS are better than mini-PCNL alone. ECIRS also showed good outcomes in impacted upper ureteric stones. Recently, some studies have explored the robotic-assisted kidney puncture in ECIRS that avoided multitrack surgery, especially in anomalous kidney and staghorn stones.

SUMMARY

ECIRS is ready for primetime in endourology and can be considered the next gold-standard for a personalized stone approach in complex kidney stones.

Comparative Study of Prone Position Variations for Percutaneous Nephrolithotomy

Objective

In this comparative study, we evaluated the results of flat prone and prone hip flexed percutaneous nephrolithotomy in terms of efficacy and safety to contribute to the optimal prone percutaneous nephrolithotomy position.

Materials and Methods

Data of the patients who underwent percutaneous nephrolithotomy operations in a flat-prone or prone hip flexed positions due to renal pelvis and/or ≥2 Calix filling stones between January 2016 and January 2022 were collected retrospectively. Demographic data of the patient groups in different prone positions as well as clinical findings, stone characteristics and operative data were analyzed. The groups were also compared in terms of post-operative findings and complications.

Results

The average age and CROES scores of patients included in the study were 47.15±15.6 years and 221.76±62.49, respectively. There was no statistically significant difference between the two groups in terms of patient demographic data, stone-free status and complication rates. Operation Room Time (ORT) (min) in flat prone PCNL group was shorter in average (100.57±32.74 min vs 92.32±28.75 min, p = 0.041) and duration with nephrostomy (days) and hospitalization (days) parameters were statistically significantly shorter in prone hip flexed PCNL (respectively, p < 0.001; p = 0.005).

Conclusion

Flat-prone PCNL provides significantly shorter ORT. However, the time with nephrostomy and hospitalization with the prone hip flexed PCNL were shorter than flat-prone position. The findings will guide the optimal prone PCNL position.

Impact of pelvicalyceal anatomical variation on surgical outcomes of endoscopic combined intrarenal surgery

Objectives

The objective of this work is to investigate the impact of the pelvicalyceal anatomical system (PCS) on calyceal stone formation and surgical outcomes of endoscopic combined intrarenal surgery (ECIRS) for renal and/or proximal ureteral stones with a diameter >15 mm.

Patients and methods

PCS was classified as Type I (single pelvis) or Type II (divided pelvis) according to the simple anatomical Takazawa classification. Using prospectively collected data from January 2016 to April 2020, 219 patients were retrospectively reviewed. After excluding patients who underwent a staged procedure, had hydronephrosis greater than grade 2, prior nephrostomy tubes, and failed to access the renal collecting system, 115 patients (Type I: 81, Type II: 34) were included, and the distribution of calyceal stones and surgical outcomes in ECIRS were compared between Types I and II PCS.

Results

The median number of renal stone calyces in the Type II group was significantly more than that in the Type I group (p = 0.016). In particular, the Type II group possessed more upper stone calyces. Multivariate logistic regression analysis revealed that Type II PCS was associated with an increased odds ratio (OR) for the presence of upper stone calyces (OR: 2.93, p = 0.018). The stone-free (SF) status at 1 month after surgery, confirmed by abdominal plain radiography, was significantly higher in the Type I group compared with that in Type II (67.9% vs. 39.4%, respectively; p = 0.006). The requirement for additional surgical interventions was significantly higher in the Type II group compared with that in Type I (35.4% vs. 7.4%, respectively; p < 0.001). Multivariate analysis revealed that the number of stone calyces (OR: 4.26; p = 0.001) and Type II PCS (OR: 3.43; p = 0.009) were independent predictors of residual stones after ECIRS.

Conclusion

We first revealed that the anatomic properties of PCS play a role in both upper calyceal stone formation and in the success of the ECIRS procedure. Because the SF rate in Type II PCS was significantly lower than that in Type I PCS, additional percutaneous nephrolithotomy tracts might be required, even for ECIRS.

The efficacy and safety of one-stage endoscopy combined with intrarenal surgery (mini-nephrostomy tract) in the prone split-leg position for complex renal calculi

Background

The goal of this study was to determine the safety and efficacy of endoscopic combined intrarenal surgery (ECIRS) performed in the prone split-leg position for the treatment of complex renal stones.

Materials and methods

A mature ECIRS protocol was designed. Retrospective analysis was conducted of medical records between January 2020 and December 2021 of patients with complex renal stones at one center who underwent ECIRS by 2 skilled surgeons using retrograde flexible ureteroscopy and mini-percutaneous nephrolithotomy in the prone split-leg position.

Results

A total of 44 patients were included in this study. Mean stone size was 26.1 ± 12.7 mm, and the number of calyces involved was 4.36 ± 2.09. Mean operative time was 71.1 ± 21.8 minutes. Postoperative decline in hemoglobin was 15.8 ± 9.8 g/L. Seventy-five percent of patients achieved stone-free status. The mean number of residual stones was 2.8 ± 2.3, and the mean residual stone size was 10.30 ± 4.76 mm. Six patients (13.6%) developed postoperative complications, including 4 with fever during the first 2 days postoperatively and 2 patients with transient postoperative pain. No patients developed severe complications.

Conclusions

Endoscopic combined intrarenal surgery in the prone split-leg position can be performed safely by experienced surgeons using retrograde flexible ureteroscopy in conjunction with mini-percutaneous nephrolithotomy as a successful technique for the treatment of complex renal stones.

International Alliance of Urolithiasis guideline on retrograde intrarenal surgery

OBJECTIVES

To set out the second in a series of guidelines on the treatment of urolithiasis by the International Alliance of Urolithiasis that concerns retrograde intrarenal surgery (RIRS), with the aim of providing a clinical framework for urologists performing RIRS.

MATERIALS AND METHODS

After a comprehensive search of RIRS-related literature published between 1 January 1964 and 1 October 2021 from the PubMed database, systematic review and assessment were performed to inform a series of recommendations, which were graded using modified GRADE methodology. Additionally, quality of evidence was classified using a modification of the Oxford Centre for Evidence-Based Medicine Levels of Evidence system. Finally, related comments were provided.

RESULTS

A total of 36 recommendations were developed and graded that covered the following topics: indications and contraindications; preoperative imaging; preoperative ureteric stenting; preoperative medications; peri-operative antibiotics; management of antithrombotic therapy; anaesthesia; patient positioning; equipment; lithotripsy; exit strategy; and complications.

CONCLUSION

The series of recommendations regarding RIRS, along with the related commentary and supporting documentation, offered here should help provide safe and effective performance of RIRS.

International Alliance of Urolithiasis (IAU) Guideline on percutaneous nephrolithotomy

The International Alliance of Urolithiasis (IAU) would like to release the latest guideline on percutaneous nephrolithotomy (PCNL) and to provide a clinical framework for surgeons performing PCNLs. These recommendations were collected and appraised from a systematic review and assessment of the literature covering all aspects of PCNLs from the PubMed database between January 1, 1976, and July 31, 2021. Each generated recommendation was graded using a modified GRADE methodology. The quality of the evidence was graded using a classification system modified from the Oxford Center for Evidence-Based Medicine Levels of Evidence. Forty-seven recommendations were summarized and graded, which covered the following issues, indications and contraindications, stone complexity evaluation, preoperative imaging, antibiotic strategy, management of antithrombotic therapy, anesthesia, position, puncture, tracts, dilation, lithotripsy, intraoperative evaluation of residual stones, exit strategy, postoperative imaging and stone-free status evaluation, complications. The present guideline on PCNL was the first in the IAU series of urolithiasis management guidelines. The recommendations, tips and tricks across the PCNL procedures would provide adequate guidance for urologists performing PCNLs to ensure safety and efficiency in PCNLs.

Endoscopic combined intrarenal surgery in the prone split-leg position versus Galdakao-modified supine Valdivia position for the management of partial staghorn calculi

OBJECTIVE

To evaluate and compare the outcome of ECIRS in the treatment of partial staghorn renal calculi in both prone split-leg positions versus GMSV positions with regard to; technical aspects, success rate, operative time, complications, safety, and effectiveness of both approaches.

PATIENTS AND METHODS

Between October 2018 and August 2021, 66 patients with partial staghorn calculi were enrolled in this prospective comparative study. Patients were randomly divided according to a 1:1 ratio into two groups. Group A included 33 patients who were treated by (ECIRS) in the prone split-leg position, and group B included 33 patients who were treated by (ECIRS) in the Galdakao-modified supine Valdivia (GMSV) position.

RESULTS

No significant statistical difference between both groups regarding the mean age (p = 0.448), mean body mass index (BMI) (p = 0.137), mean stone burden (p = 0.435), mean operative time (p = 0.541) and the number of calyces located in branched stones (p = 0.628). The mean hospital stay was 6.71 ± 1.12 days for group A and 6.66 ± 1.10 days for group B patients (p = 0.724). The final SFR was achieved in (29)87.87% and (30)90.9% of group A & B patients, respectively (p = 0.694). No significant difference was detected between both groups in perioperative complication rates.

CONCLUSION

ECIRS is safe and effective in treating partial staghorn calculi either in the prone split-leg position or in the Galdakao-modified supine Valdivia position, with comparable outcomes and no statistically significant difference between both positions.

Comparison of postoperative outcomes of mini percutaneous nephrolithotomy and standard percutaneous nephrolithotomy: a meta-analysis

Our study was aimed to evaluate the postoperative outcomes of Mini Percutaneous Nephrolithotomy (Mini-PCNL) and Standard Percutaneous Nephrolithotomy (Standard-PCNL) to determine the optimum option for patients with renal calculi. For publications published between January 2010 and April 2021, a comprehensive search of the PubMed, Cochrane Library, Web of Science, and EMBASE databases was done. The literatures were chosen based on the criteria for inclusion and exclusion. After the data were retrieved and the quality was assessed, the meta-analysis was performed using Review Manager Software (RevMan 5.4.1, Cochrane Collaboration, Oxford, UK). We selected 20 trials with a total of 4953 people out of 322 studies. There were 2567 patients treated with Mini-PCNL and 2386 patients treated with Standard-PCNL. Meta-analysis results showed no difference in stone-free rates (SFR, P = 0.93), fever (P = 0.83), and postoperative pain (VAS score) (P = 0.21) between Mini-PCNL and Standard-PCNL. Patients in the Mini-PCNL group experienced shorter hospital stay (P < 0.0001), less hemoglobin drop (P < 0.00001), less blood transfusion (P < 0.00001), higher postoperative tubeless (P = 0.0002), and fewer complications including bleeding (P = 0.01), perforation (P = 0.03), and leakage (P = 0.01). Compared with Standard-PCNL, operative time was longer in the Mini-PCNL group (P = 0.0005). Mini-PCNL had a shorter hospital stay, less hemoglobin drop, less blood transfusion, greater postoperative tubeless, fewer complications, and a longer operational time when compared to Standard-PCNL. SFR, fever, and postoperative pain were similar in both of them. Mini-PCNL may be a superior option for patients with proper size renal calculi.

Abdominal compartment syndrome after endoscopic combined intrarenal surgery

Introduction

We report a case of abdominal compartment syndrome due to hydroperitoneum after endoscopic combined intrarenal surgery.

Case presentation

A 56-year-old woman with a left staghorn calculus underwent endoscopic combined intrarenal surgery as a two-staged procedure and developed a distended abdomen, cyanosis of both legs, and hypotension immediately after the second operation. A computed tomography scan showed hydroperitoneum. We performed urgent laparotomy and evacuated approximately 2 L of nearly transparent fluid. No peritoneal injury was detected. Postoperatively, she required intensive care for shocked liver and acute kidney injury.

Conclusion

Hydroperitoneum after endoscopic combined intrarenal surgery is a rare complication and may lead to abdominal compartment syndrome or a condition where intra-abdominal pressure exceeds 20 mmHg, causing impaired organ perfusion. Delayed drainage can be fatal.

The Safety and Efficacy of Endoscopic Combined Intrarenal Surgery (ECIRS) versus Percutaneous Nephrolithotomy (PCNL): A Systematic Review and Meta-Analysis

Purpose

Our aim is to evaluate the safety and efficacy of endoscopic combined intrarenal surgery compared to percutaneous nephrolithotomy to guide practitioners and inform guidelines.

Materials and Methods

A detailed database search was performed in PubMed, OVID, Scopus, and Web of Science in October 2021 to identify articles pertaining to ECIRS published between 2001 and 2021.

Results

Four nonrandomized comparative studies and one RCT were identified, yielding five studies with a total of 546 patients (ECIRS/mini-ECIRS, n = 277; PCNL/mini-PCNL, n = 269). Subjects in these five studies met the predefined inclusion criteria established by two reviewers (J.E.A. and R.L.S.) and were therefore eligible for analysis. The results demonstrated that ECIRS was associated with a higher SFR (OR: 4.20; 95% CI: 2.79, 6.33; p < 0.00001), fewer complications (OR: 0.63; 95% CI: 0.41, 0.97; p=0.04), and a shorter hospital stay (WMD: −1.27; 95% CI: −1.55, −0.98; p < 0.00001) when compared to PCNL. There were no statistically significant differences in blood transfusions (OR: 0.45; 95% CI: 0.12, 1.68; p=0.24), operative time (SMD: −1.05; 95% CI: −2.42, 0.31; p=0.13), or blood loss (SMD: −1.10; 95% CI: −2.46, 0.26; p=0.11) between ECIRS and PCNL.

Conclusions

ECIRS may be a more suitable approach for the surgical management of large and complex kidney stones currently indicating PCNL due to its superior efficacy with comparable surgical time and complication rate, though it is thought that a lack of resources and properly trained personnel may preclude ECIRS from becoming the standard. It is our impression that ECIRS may become the preferred technique in the endourologic community corresponding to the evolutionary sequence of percutaneous stone surgery.

Endoscopic Combined Intrarenal Surgery vs Percutaneous Nephrolithotomy for Large and Complex Renal Stone: A Systematic Review and Meta-Analysis

Background: Managing complex and large renal stones with percutaneous nephrolithotomy (PCNL) is difficult because of the likelihood of residual stones and multiple access. Endoscopic combined intrarenal surgery (ECIRS) is introduced as an improvement to the procedure to manage stones in one session. The objective of this systematic review and meta-analysis is to compare the efficacy and safety between ECIRS and PCNL for treating large and complex renal stones. Materials and Methods: We conducted a systematic review in the Embase, Scopus, and MEDLINE databases based on the 2020 Preferred Reporting Items for Systematic Review and Meta-Analyses guideline. Eligible studies comprised both randomized and nonrandomized studies comparing ECIRS and PCNL. Results: A total of five nonrandomized studies and one randomized controlled trial were included. The analysis was divided into two subgroups based on the PCNL type, a conventional PCNL (cPCNL) and a mini-PCNL (mPCNL). The one-step stone-free rate (SFR) of ECIRS were significantly higher compared with both the cPCNL (odds ratio [OR] 5.14, 95% confidence interval [CI] 2.54 to 10.4, p < 0.001) and mPCNL (OR 4.27, 95% CI 2.57-7.1, p < 0.001). There were no significant differences in mean operative time and hemoglobin drop between both groups (p > 0.05). The use of auxiliary procedures was significantly higher in both PCNL groups compared with the ECIRS group (OR 0.19, 95% CI 0.13-0.30, p < 0.001). The overall complication rate of ECIRS was lower compared with PCNL (OR 0.43, 95% CI 0.21-0.85, p = 0.02), especially urosepsis, in which the incidence was lower compared with cPCNL (OR 0.14, 95% CI 0.02-0.78, p = 0.02), but not mPCNL (p > 0.05). Conclusion: ECIRS is an effective and safe treatment particularly for large and complex nephrolithiasis, with significantly higher one-step SFR, a lower necessity for auxiliary procedures, and a lower complication rate compared with PCNL.

Comparison of mini endoscopic combined intrarenal surgery and multitract minimally invasive percutaneous nephrolithotomy specifically for kidney staghorn stones: a single-centre experience

BACKGROUND

Staghorn stones require surgical treatment to prevent serious complications. Multitract percutaneous nephrolithotomy (PNL) causes great renal parenchymal injury and blood loss. One-stage endoscopic combined intrarenal surgery (ECIRS) entails the combined use of antegrade nephroscope and retrograde flexible ureteroscope to clear the staghorn stone, which may overcome the limitations of multitract PNL. We aimed to compare the perioperative outcomes of mini ECIRS and multitract minimally invasive PNL in staghorn stone management.

METHODS

This was a retrospective single-center study of patients with staghorn stones who underwent ECIRS (n = 17) or multitract minimally invasive PNL (n = 17) between January 2018 and September 2021.

RESULTS

There was a significant between-group difference with respect to Guy's stone score. Stone size, stone burden (ECIRS group, 21.41 cm3; multitract minimally invasive PNL group, 20.88 cm3 [P = 0.94]), and degree of hydronephrosis were comparable in the two groups. There was no significant between-group difference with respect to one-step or final stone-free rates. The mean operative time was also not significantly different between the groups (ECIRS group, 140 min; multitract minimally invasive PNL group, 183 min [P = 0.63]). ECIRS was associated with significantly lesser postoperative pain (visual analog scale; ECIRS group: 0; multitract minimally invasive PNL group: 2.7 [P < 0.001]). Hemoglobin loss, postoperative blood transfusion rate, complications, and length of hospital stay were comparable in the two groups.

CONCLUSION

Both mini ECIRS and multitract minimally invasive PNL were effective and safe for the management of renal staghorn stones with comparable operation time and stone-free rate, and complications. ECIRS was associated with less severe postoperative pain.

The First 100 Cases of Endoscopic Combined Intrarenal Surgery in Korea: Matched Cohort Analyses versus Shock-Wave Lithotripsy

PURPOSE

This study presents our initial experience with endoscopic combined intrarenal surgery (ECIRS) for large renal stones and compares the results of a propensity score-matched cohort of patients undergoing shock-wave lithotripsy (SWL).

MATERIALS AND METHODS

A total of 100 adults underwent ECIRS for renal stones between August 2017 and January 2019. For comparison, 2172 patients who underwent a first session of SWL between January 2005 and May 2018 were included in the SWL cohort. Propensity score matching was performed using maximal stone length (MSL), mean stone density (MSD), and stone heterogeneity index (SHI) scores. Stone-free rate (SFR) and success rate were compared between ECIRS and SWL.

RESULTS

In the ECIRS group, the mean MSL, mean MSD, and mean SHI were 28.7±15.2 mm, 1013.9±360.0 Hounsfield units (HU), 209.4±104.0 HU, respectively. The SFR was 70%, and the success rate was 82.0% in this group. Although the ECIRS group had larger, harder, and more homogeneous stones than the SWL group, ECIRS showed a higher SFR and success rate than SWL. After propensity-score matching, SFR and success rate remained higher with ECIRS than with SWL (both, p<0.001). In multivariate logistic regression, smaller stone size [odds ratio (OR): 0.947, 95% confidence interval (CI): 0.913-0.979, p=0.002] and lower Seoul National University Renal Stone Complexity score (OR: 0.759, 95% CI: 0.610-0.935, p=0.011) were independent predictors of successful ECIRS.

CONCLUSION

ECIRS showed a higher SFR and success rate than SWL for large renal stones. Smaller stone size and lower complexity of stones were associated with a higher likelihood of successful ECIRS.

Robot-Assisted Mini-Endoscopic Combined Intrarenal Surgery for Complex and Multiple Calculi: What Are the Real Advantages?

Background: To determine the stone-free rates (SFR) with robot-assisted mini-endoscopic combined intrarenal surgery (mini-ECIRS) and evaluate the impact of intraoperative assessment of stone-free status compared to postoperative non-contrast computed tomography (NCCT) scan findings. Methods: A total of 42 consecutive patients (44 renal units) diagnosed with complex/multiple renal stones were enrolled and reviewed in a retrospective manner. While retrograde access with the flexible scope was performed by using Avicenna Roboflex, mini-percutaneous nephrolithotomy was performed through a 16.5F sheath. Demographic, clinical characteristics of the cases along with perioperative complications were recorded, analyzed, and compared to the reported data in the literature. Results: Forty-two renal units (95.5%) were endoscopically confirmed to be stone-free at the end of the procedure, of which all were confirmed to be stone-free in postoperative NCCT examination. Complications were observed in 3 of the 42 (7.1%) patients, which were classified as Clavien grade I. The mean operation and fluoroscopy time were 103.7 ± 20.6 minutes and 71 ± 13.7 seconds, respectively. Conclusion: Our results demonstrate that robot-assisted mini-ECIRS could reveal high SFR in complex and multiple stones. In addition, endoscopic flexible ureteroscopic evaluation of the collecting system at the end of the procedure could let the surgeon predict stone-free status more reliably and successfully.

One-stage efficacy of single tract minimally invasive ECIRS in the improved prone frog split-leg position for staghorn stones

OBJECTIVE

To explore the feasibility, safety, and effectiveness of single tract minimally invasive endoscopic combined intrarenal surgery (stmECIRS) in the improved prone frog split-leg position for staghorn stones.

METHOD

A total of 83 patients with staghorn stones were retrospectively reviewed between January 2018 and June 2021. According to surgical procedure and position, patients were divided into a group of single tract minimally invasive percutaneous nephroscopy (stmPNL) in the prone position and a group of stmECIRS in the improved prone frog split-leg position (turned to the prone position after preset the flexible ureteroscope sheath in lithotomy position, meanwhile, bend both hips and knees to be frog abduction). Demographic characteristics, laboratory tests, stone characters, surgical information, stone-free rate (SFR), and perioperative complications were observed and analyzed.

RESULTS

There were no significant differences in demographic characteristics, changes level of Scr and Hb, stone size, radiation density, length of hospital stay, and operation time between the two groups. One-stage SFR in the stmECIRS group was significantly higher than that in the stmPNL group (84.4% vs. 57.9%) (P = 0.007), only 2 patients required blood transfusion after surgery (P = 0.862), and other postoperative complications were not statistically significant (P = 0.345).

CONCLUSIONS

StmECIRS in improved prone frog split-leg position has a higher one-stage SFR than stmPNL for staghorn renal stones, and without complications increased, which is a safe, efficient and feasible treatment.

Efficacy of fosfomycin in preventing infection after endoscopic combined intrarenal surgery in periods of limited supply of first- and second-generation cephalosporins

OBJECTIVES

In March 2019, cefazolin was unavailable owing to difficulty in procuring the active ingredient. Furthermore, the supply of alternative drugs, such as cefotiam and cefmetazole, was limited. In the Department of Nephro-Urology, fosfomycin-based drugs are used as substitutes for cefazolin, which is a perioperative prophylactic antibacterial drug. Herein, we investigated the effectiveness of fosfomycin sodium and cefotiam in preventing infection after endoscopic combined intrarenal surgery as a retrospective preliminary study.

METHODS

A total of 200 patients who underwent endoscopic combined intrarenal surgery at our department between August 2017 and January 2021 were included. The patients were administered cefotiam (n = 95) or fosfomycin (n = 105) as perioperative antibacterial agents. There were no significant differences in the median age or surgery time between the cefotiam and fosfomycin groups. Propensity score matching was performed to match the preoperative urine bacterial counts of both groups. Sixty-eight patients were selected from each group.

RESULTS

The median postoperative hospital stay duration was 4 days for the two groups. The median maximum postoperative temperatures were 37.5 and 37.4°C, respectively. There were no significant differences between the maximum postoperative temperatures in both groups. Furthermore, there were no differences between the groups regarding the white blood cell counts, C-reactive protein levels, and aspartate aminotransferase and alanine aminotransferase levels postoperatively, as well as in terms of postoperative fever requiring additional antibiotics.

CONCLUSIONS

During a period of difficulty in acquiring cefazolin and cefotiam, the use of fosfomycin allowed us to continue with the procedure without increased clinical complications.

Endoscopic Combined Intrarenal Surgery Versus Percutaneous Nephrolithotomy for Complex Renal Stones: A Systematic Review and Meta-Analysis

Background: Endoscopic combined intrarenal surgery (ECIRS) adds ureteroscopic vision to percutaneous nephrolithotomy (PCNL), which can be helpful when dealing with complex renal stones. Yet, there is still no consensus on the superiority of ECIRS. We aimed to critically analyze the available evidence of studies comparing efficacy, safety, bleeding risk, and efficiency of ECIRS and PCNL. Methods: We searched for studies comparing efficacy (initial and final stone-free rate), safety (postoperative fever, overall and severe complications), efficiency (operative time and hospital stay) and bleeding risk between ECIRS and PCNL. Meta-analysis was performed. Results: Seven studies (919 patients) were identified. ECIRS provided a significantly higher initial stone-free rate, higher final stone-free rate, lower overall complications, lower severe complications, and lower rate of requiring blood transfusion. There was no difference between the two groups in terms of postoperative fever, hemoglobin drop, operative time, and hospital stay. In the subgroup analysis, both minimally invasive and conventional ECIRS were associated with a higher stone-free rate and lower complication outcomes. Conclusions: When treating complex renal stones, ECIRS has a better stone-free rate, fewer complications, and requires fewer blood transfusions compared with PCNL. Subgroups either with minimally invasive or conventional intervention showed a consistent trend.

Application of a new position in endoscopic combined intrarenal surgery: modified prone split-leg position

Background

Endoscopic combined intrarenal surgery (ECIRS) is well established as a minimally invasive procedure for the treatment of multiple urolithiasis. The position is the key to the perfect combination of percutaneous nephrolithotomy (PCNL) and retrograde intrarenal surgery (RIRS). Galdakao-modified supine Valdivia (GMSV) and prone split-leg positions are widely used. However, both positions have their own advantages and disadvantages. This study aimed to evaluate the effect of ECIRS in the treatment of multiple urolithiasis in the modified prone split-leg position.

Patients and methods

A total of 96 patients with multiple urolithiasis underwent ECIRS in modified prone split-leg position from September 2017 to January 2021. Relevant demographic and clinical data were analysed retrospectively. Clinical outcomes, such as the stone free rate, complications and postoperative hospital stay were evaluated. The chi-square test was used to compare categorical variables and Student’s t test was applied for continuous variables of the treatment groups.

Results

The mean renal stone size was 32.5 ± 10.7 mm and renal stone surface area was 712.2 ± 264.8 mm². The mean ureteral stones size was 24.8 ± 12.3 mm. The mean surgical time was 82.2 ± 38.3 min. The incidence of complications was 16.7%, and they were mainly grade 1 and grade 2. No complications occurred above grade 3. The stone was completely removed in 75 (78.1%) patients in a single operation. The risk factors affecting the stone-free rate of ECIRS were analysed, and only the number of involved calyces by stone was found to be significant (p = 0.01).

Conclusion

ECIRS is safe and effective in the treatment of multiple renal calculi or multiple renal calculi with ipsilateral ureteral calculi in the modified prone split-leg position. The modification of the prone split-leg position makes the retrograde operation more convenient, which is conducive to the combination of RIRS and PCNL.

Nonpapillary prone endoscopic combined intrarenal surgery: effectiveness, safety and tips, and tricks

PURPOSE

To evaluate the effectiveness and safety of nonpapillary prone endoscopic combined intrarenal surgery (ECIRS) and provide practical tips and tricks for the successful accomplishment of the procedure respecting the anatomical particularities.

MATERIAL AND METHODS

This study is an analysis of a prospectively collected database including all cases of ECIRS performed between January 2019 and December 2021 in a high-volume tertiary center. All patients underwent the procedure in prone-split leg position. A nonpapillary renal puncture was performed. The used access sheaths were 22Fr or 30Fr. Lithotripsy was performed anterogradely with a dual-energy lithotripter with incorporated suction and retrogradely with holmium Yttrium-Aluminum-Garnet laser.

RESULTS

A total of 33 patients were included. The initial stone-free rate (SFR) was 84.8% and the final SFR was 90.9%. The median stone size was 35 mm and 60% of patients had staghorn calculi. The prevalence of renal abnormalities was 21.3%, including 3 cases of horseshoe kidney, 2 cases of malrotation and 2 cases with complete duplicated systems. The median operative time was 47 min. The median hospital stay was 3 days and median hemoglobin loss was 1.2 gr/dL. Overall, the complication rate was 9.1%, all being Grade II complications (n = 2 fever and n = 1 transient bleeding).

CONCLUSIONS

Nonpapillary prone ECIRS is an effective and safe procedure. Standardization of the procedure is critical to achieve good outcomes. Patients who benefit the most are probably the ones where additional punctures can be avoided using this technique, namely patients with renal abnormalities, incrusted ureteral stents and staghorn stones.

Comparison of the Efficacy of ShuoTong Ureteroscopy and Simple Flexible Ureteroscopy in the Treatment of Unilateral Upper Ureteral Calculi

Background: ShuoTong ureteroscopy (Sotn-ureteroscopy, ST-URS), a new lithotripsy operation method developed on the basis of ureteroscopy, is widely used to treat ureteral stones in China. Its composition includes rigid ureteral access sheath, standard mirror, lithotripsy mirror, and ShuoTong perfusion aspirator (ST-APM). Here, we compared the efficacy and safety of the ST-URS and the flexible ureteroscope (F-URS) holmium laser lithotripsy in the treatment of unilateral upper ureteral calculi. Methods: Retrospective analysis was conducted on the clinical data of 280 patients who met the inclusion 1) urinary tract CT was diagnosed with unilateral single upper ureteral calculi above the L4 lumbar spine; 2) patient age was from 18 to 80 years old; 3) patients were informed and consented to this study; and 4) patients were approved by the hospital ethics committee (proof number: KY-2019-020) and the exclusion criteria for unilateral upper ureteral calculi in the First Affiliated Hospital of Xiamen University from January 2018 to November 2020, and they were divided into the ST-URS group and the flexible ureteroscopy (F-URS) group. Results: The stone-free rate of 1 day after operation of the ST-URS group was significantly higher than the F-URS group (63.71 vs. 34.62%, P < 0.0001). The operative time (38.45 vs. 46.18 min, P = 0.005) and hospitalization cost (27,203 vs. 33,220 Yuan, P < 0.0001) of the ST-URS group were significantly lower than the F-URS group. There were no significant differences in the success rate of ureteral access sheath placement, operative blood loss, stone-free rate of 1 month after operation, postoperative complications, postoperative hospital stay, and postoperative visual analog scale (VAS) pain score between the two groups (P > 0.05). In subgroups of a diameter of calculi ≥ 1.5 cm, calculi CT numerical value ≥ 1,000 Hounsfield unit and the preoperative hydronephrosis range ≥ 3.0 cm, ST-URS shows more advantages in the operative time, stone-free rate of 1 day after the operation, the hospitalization cost, and the incidence of postoperative complications. Conclusion: In unilateral upper ureteral stones treated with a holmium laser, compared with the simple F-URS, the ST-URS has a shorter operative time, lower hospitalization cost, and a higher stone-free rate of 1 day after the operation, suggesting that the ST-URS could be more widely applied in clinics.

Comparison of the safety and efficacy between the prone split-leg and Galdakao-modified supine Valdivia positions during endoscopic combined intrarenal surgery: A multi-institutional analysis

OBJECTIVES

To evaluate the safety and efficacy of the prone split-leg and the Galdakao-modified supine Valdivia positions during endoscopic combined intrarenal surgery.

METHODS

A multi-institutional, retrospective cohort study was conducted between January 2014 and December 2018. The stone-free and complication rates were compared between the prone split-leg and the Galdakao-modified supine Valdivia positions. Anatomical variations were evaluated using contrast-enhanced computed tomography imaging.

RESULTS

In total, 118 and 100 patients underwent endoscopic combined intrarenal surgery in the prone split-leg and Galdakao-modified supine Valdivia positions, respectively. Renal punctures in the prone split-leg position were predominantly executed through the lower calyces (78.0%), whereas those in the Galdakao-modified supine Valdivia position were primarily performed through the middle calyces (64.0%; P < 0.001). Surgical duration in the prone split-leg position was significantly shorter than that in the Galdakao-modified supine Valdivia position (106.5 vs 126.0 min; P = 0.0459). There were no significant differences in the stone-free rate between the two positions (78.8% vs 76.0%; P = 0.629). Incidences of urinary tract injury (P = 0.033) and febrile urinary tract infection (23.7% vs 10.0%; P = 0.011) in the prone split-leg position were significantly higher than that in the Galdakao-modified supine Valdivia position. The tilt of the major renal axis was significantly greater in the prone position than the corresponding values in the oblique position (19.4° vs 8.5°; P = 0.019).

CONCLUSIONS

Anatomical variation might result in the differences of renal puncture calyx. Endoscopic combined intrarenal surgery in the Galdakao-modified supine Valdivia position may bring equal stone-free status, with a longer surgical time but fewer complications including febrile urinary tract infection and urinary tract injury than the prone split-leg position.

Comparison of the Prone Split-Leg Position with the Traditional Prone Position in Percutaneous Nephrolithotomy: A Propensity Score-Matching Study

Background and Objective: Several positions have been described for percutaneous nephrolithotomy (PCNL). The aim of this study was to compare the safety and effectiveness of the traditional prone position PCNL (TP-PCNL) and the prone split-leg position PCNL (PSL-PCNL). Patients and Methods: A retrospective review was made of the data of 212 patients who underwent prone PCNL in PSL or TP between January 2017 and November 2019. The demographic and preoperative clinical data were used for propensity score-matching (PSM). Following the PSM based on a multivariable logistic regression model, the PSL-PCNL and TP-PCNL groups were compared in preoperative, perioperative, and postoperative parameters. All surgical procedures were performed by an experienced endourologist. Results: After PSM, 51 patients from the PSL-PCNL group were matched to 51 TP-PCNL patients. The stone burden was not statistically significant between the two groups (p = 0.388). The mean operation time of the two groups was significantly different (81.5 ± 32.4 minutes vs 93.1 ± 25.9 minutes, respectively, p = 0.026). The hemoglobin decrease in the PSL-PCNL group was greater than that in the TP-PCNL group (-17.7 ± 16.9 g/L vs 13.1 ± 10.9 g/L, p < 0.001). Both groups had similar stone-free rates after 2 weeks (p = 0.49). No significant difference was observed between the groups in the total complication rate (p = 1). Conclusions: The application of PSL in PCNL simplifies the surgical procedure and shortens the operating time. Another important advantage is that it allows retrograde intrarenal surgery and ureteroscopy to be performed simultaneously. We recommend the PSL to be applied in PCNL for renal stone patients.

Ambulatory Percutaneous Nephrolithotomy in a Free-Standing Surgery Center: An Analysis of 500 Consecutive Cases

INTRODUCTION

Percutaneous Nephrolithotomy (PCNL) is an effective procedure for removal of large kidney stones; however, PCNL has traditionally been reserved for inpatient surgery. Certain cases are being performed entirely at an ambulatory surgery center (ASC), known as ambulatory PCNL (aPCNL).

MATERIALS AND METHODS

Five hundred consecutive PCNL procedures performed at a free-standing ASC between April 2015 and February 2019 were analyzed. Patient demographics, stone characteristics, operative characteristics, and post-operative data including transfer to hospitals, 30-day readmissions, and complications > Clavien I were recorded.

RESULTS

The mean age of patients undergoing PCNL at the ASC was 57 (range: 16-86) and BMI 30 (16-49). ASA compositions are as follows: ASA 1 (6.5%), ASA 2 (56.2%), ASA 3 (37.2%) and ASA 4 (0. 1%). The mean stone burden was 30 mm (5-140). Standard tract dilation (24-30 French) comprised 77% of cases. 92% of cases were performed with a single tract and 99% of cases had a ureteral stent as the only form of drainage (tubeless PCNL). The mean operative time was 104 minutes (32-305) and post anesthesia care unit (PACU) time was 97 minutes (37-247). The predicted stone free rate was 84%. Twelve patients (2.4%) required transfer to hospital and the 30-day readmission rate was 4.2%.

CONCLUSION

aPCNL is a safe and feasible procedure if performed by a high volume endourologist, even within the confines of a free-standing ASC. It is our opinion that the utilization of ECIRS facilitates high stone free rates with minimal morbidity and low readmission rates.

Ureteroscopy-assisted puncture for ultrasonography-guided renal access significantly improves overall treatment outcomes in endoscopic combined intrarenal surgery

OBJECTIVES

To assess the impact and availability of ureteroscopy-assisted puncture for percutaneous renal access during ultrasonography-guided miniaturized (mini)-endoscopic combined intrarenal surgery for large volume renal and/or proximal ureteral stones.

METHODS

We conducted a multi-institutional retrospective cohort study for urolithiasis treatment. Data from a total of 313 patients who underwent mini-endoscopic combined intrarenal surgery to treat renal and/or ureteral stones between January 2016 and April 2020 were collected. We compared the outcomes between ultrasonography-guided mini-endoscopic combined intrarenal surgery with and without ureteroscopy-assisted puncture (ureteroscopy-assisted puncture(+) group [n = 126] and ureteroscopy-assisted puncture(-) group [n = 187] group, respectively). The primary outcome was requirement for additional surgical intervention. Secondary outcomes were stone-free rate, complications and total procedure, fluoroscopy, hospital stay, and postoperative ureteral stent placement durations.

RESULTS

The ureteroscopy-assisted puncture(+) group had a lower additional surgical intervention rate and a higher stone-free rate immediately after and 3 months after surgery than the ureteroscopy-assisted puncture(-) group (5.6% vs 19.7%, P < 0.001; 82.5% vs 65.8%, P = 0.001; 59.5% vs 44.6%, P = 0.011). The median total procedure, fluoroscopy, and postoperative ureteral stent placement durations were 18 min, 3 min, and 5 days shorter, respectively, in the ureteroscopy-assisted puncture(+) group. Multivariate analyses showed that ureteroscopy-assisted puncture was associated with a decreased risk of additional surgical intervention (odds ratio 0.31, P = 0.011) and postoperative infection (odds ratio 0.34, P = 0.003) and decreased total procedure (estimate = -11 min; P = 0.011), fluoroscopy (estimate = -3 min; P = 0.034), and postoperative ureteral stent placement (estimate = -8 days; P = 0.011) durations. Female patients and those with smaller stone volumes or without hydronephrosis were identified as ideal ureteroscopy-assisted puncture candidates.

CONCLUSIONS

Ureteroscopy-assisted puncture during mini-endoscopic combined intrarenal surgery could provide favorable surgical outcomes, especially in female patients without collecting system obstruction.

Effect of Preoperative Double-J Ureteral Stenting before Flexible Ureterorenoscopy on Stone-free Rates and Complications

The effect of preoperative Double-J (DJ) ureteral stenting before flexible ureterorenoscopy (FURS) in the treatment for urinary stones was evaluated. We retrospectively enrolled 306 consecutive patients who underwent FURS from Jan. 2014 to Dec. 2017. All the patients were classified into two groups according to whether they had DJ ureteral stenting before FURS. Baseline characteristics (age, sex, stone location, stone size, surgical success rate, operation time, stone-free rate of the first day after surgery, stone-free rate of the first month after surgery, total complication rate) were compared using Chi-square test for categorical variables and Kruskal-Wallis test for continuous variables. In total, 306 patients were included in this study. The group of DJ stenting before FURS included 203 (66.3%) patients, and non-DJ stenting before FURS was observed in 103 (33.7%) patients. The group of DJ stenting before FURS was significantly associated with a shorter operation time (53.8 vs. 59.3 min, P<0.001), a higher stone-free rate of the first day after surgery (69.0% vs. 51.5%, P=0.003). However, statistical significant differences were not found in the age, sex, stone location, stone size, surgical success rate, stone-free rate of the first month after surgery (89.2% vs. 81.6%, P=0.065) and total complication rate (5.4% vs. 9.7%, P=0.161) between the two groups. Preoperative DJ ureteral stenting before FURS could reduce the operation time and increase stone-free rate of the first day after surgery. However, it might not benefit the stone-free rate of the first month after surgery and reduce the complication rate. Preoperative DJ stenting should be not routinely performed.

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.

Endoscopic combined intrarenal surgery (ECIRS) - Tips and tricks to improve outcomes: A systematic review

OBJECTIVE

This study aimed at assessing current efficacy and safety of endoscopic combined intrarenal surgery (ECIRS) for the treatment of large and/or complex urolithiasis and identifying relevant tips and tricks able to improve its outcomes, mainly deriving from the adjunct of retrograde flexible ureteroscopy to the traditional antegrade approach of percutaneous nephrolithotomy (PNL).

MATERIAL AND METHODS

A systematic review was conducted using relevant databases (Ovid Medline, PubMed, Scopus, and Web of Sciences), employing "ECIRS" as the search term in all cases, and then adding "endoscopic combined intrarenal surgery" and "flexible ureteroscopy AND percutaneous nephrolithotomy" as search terms for PubMed and Scopus. Original articles and systematic reviews were selected according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Additionally, the reference lists of the selected publications were checked manually.

RESULTS

A total of 14 studies were selected for analysis: two systematic reviews, one randomized controlled trial, five nonrandomized comparative studies, three prospective case series, and three retrospective case series. ECIRS achieves high stone-free rates and rather low/low Clavien-Dindo grade complication rates, confirming the role of retrograde ureteroscopy in the maximization of its efficacy and safety. A narrative synthesis of the most recognized tips and tricks of ECIRS is provided.

CONCLUSION

The contribution of retrograde flexible ureteroscopy during PNL is essential. It plays a dual role, both diagnostic and active, allowing tailoring of the procedure to the patient, urolithiasis, and anatomy of the collecting system and optimization of the PNL efficacy and safety. This is ECIRS: an updated, complete, and versatile version of PNL.

Impact of Stone Size, Location, and Stone Composition on the Efficacy of Extracorporeal Shock Wave Lithotripsy for Residual Stone after Percutaneous Nephrolithotomy

This study aimed to determine the impact of stone size, location and stone composition the efficacy of extracorporeal shock wave lithotripsy (ESWL) in the management of residual stone after percutaneous nephrolithotomy (PCNL). The design of this study was a retrospective that conducted between January 2012 until December 2016. The population in this study were all patients with residual stones post PCNL. Exclusion criteria were patients with multiple stones and patients with a history of previous treatment for residual stones such as nephroscopy, flexible ureterorenoscopy, ESWL or medical therapy). The variables studied in this study were stone size, stone location, and stone composition. Before ESWL was carried out, all patients underwent Kidney Ureter Bladder (KUB). After ESWL, all patients underwent ultrasonography (USG) and KUB to determine the stone clearance status. The sample of this study was 125 patients. The overall stone-free rate (SFR) of ESWL in managing post-PCNL residual stones is 72%. SFR based on stone size variable are 73.7% and 71.3% respectively for stones with a size = 5 mm and >5 mm (p = 0.78). SFR based on stone location variable was 67.1%, 75.8%, and 81.8% respectively for the residual stone located at the upper pole, middle pole and lower pole. There are no significant differences in the entire variable. This study concludes that ESWL can be used as effective additional management to treat post-PCNL residual stones with satisfactory SFR.

Combined flexible URS and percutaneous ‘through and through’ puncture of an intra-renal cyst with internalisation of drainage, to treat calyceal obstruction and recurrent stones

A 61 year old gentleman had a large renal cyst, thought to be causing a ‘pseudo-hydrocalyx’ leading to recurrent stones. Definitive treatment with laparoscopic deroofing was planned, however intra-operatively this was abandoned due to complex anatomy and scared adherent tissue. Patient went on to have a flexible ureteroscopy and ‘through and through’ puncture of an intrarenal cyst with PCNL to treat his stones and renal cyst simultaneously. CT scan 12 months later showed no new stone formation and no residual cyst. Percutaneous puncture of a renal cyst combined with flexible ureteroscopy is an effective method when treating large renal cysts.

Rigid ureteroscopy in prone split-leg position for fragmentation of female ureteral stones: A case report

BACKGROUND

Ureteroscopy is widely used in the treatment of ureteral stones due to the increased morbidity of urolithiasis. This is the first report of a case of ureteral calculi treated with rigid ureteroscopy in the modified prone split-leg position.

CASE SUMMARY

A 62-year-old Asian woman was diagnosed with a ureteral stone and underwent extracorporeal shock wave lithotripsy twice. However, the abdominal computer tomography scan showed persistent calculi on the right lower ureter. Her left hip movement was limited because of a left femoral neck fracture that did not receive proper treatment in a timely manner. She was unable to undergo surgery in the lithotomy position and refused to accept flexible ureteroscopy treatment. Therefore, rigid ureteroscopy was performed with her in the modified prone split-leg position. The ureteral calculi were successfully fragmented.

CONCLUSION

It is feasible to treat lower ureteral calculi in women in the prone split-leg position with the implementation of rigid ureteroscopy.

Definition, treatment and outcome of residual fragments in staghorn stones

Technological advances in minimally invasive treatment of stone disease and its integration with concomitant clinical practice are amongst the most important achievements in urology. Despite the wealth of information accumulated over the years and the richness of existing literature, the knowledge about the definition, treatment and outcomes of residual stone fragments after percutaneous nephrolithotomy (PNL) is still insufficient. Due to the high stone load a lot of patients with staghorn stones have residual fragments (RFs) after treatment with PNL, which depends on the size of tract, definition of stone free rate (SFR), timing of evaluation and the imaging used. No consensus exists on the imaging modality or their timing in the evaluation of possible RFs. The treatment of residual stones is apparently different depending on the facilities of the department and the preference of the surgeon, which includes active surveillance, shock wave lithotripsy (SWL), retrograde intrarenal surgery (RIRS) or a second look PNL.

Treatment of Complex Renal Calculi by Digital Flexible Ureterorenoscopy Combined with Single-Tract Super-Mini Percutaneous Nephrolithotomy in Prone Position: A Retrospective Cohort Study

Background

Advances in percutaneous nephrolithotomy (PCNL) have resulted in smaller devices that cause less trauma and bleeding, while flexible ureterorenoscopy (f-URS) allows access to any calyces. These methods are often used in isolation, but used in combination they may improve treatment of complex renal calculi. This study assessed the effectiveness and complications of f-URS combined with super-mini-PCNL (SMP) to treat complex renal calculi.

Material/Methods

A retrospective cohort analysis was made of patients with unilateral complex renal stones treated between March 2013 and December 2016. Patients were grouped according to surgical procedure: SMP (SMP Group), f-URS holmium laser lithotripsy (f-URS Group), and combined SMP and f-URS (Combined Group). The postoperative complications and complete stone-free rate were analyzed and compared among the 3 groups.

Results

A total of 140 patients with complex renal stones were included: 40 patients in the SMP Group, 55 in the f-URS Group, and 45 in the Combined Group. The complete stone-free rate 3 days after the procedure was 77.5% in the SMP Group, 78.2% in the f-URS Group, and 97.8% in the Combined Group (p=0.010). The operation time, intraoperative blood loss, and hospitalization time of the Combined Group were all significantly lower than those in the SMP Group but higher than those in the f-URS Group. The follow-up was 9 months (range, 6–12 months). There were no medium-term complications reported.

Conclusions

SMP combined with f-URS holmium laser lithotripsy in the prone position is an effective treatment for complex renal calculi.