Stone size is a predictor for residual stone and multiple procedures of endoscopic combined intrarenal surgery

Defining a learning curve for urology trainees to achieve renal access without complications in endoscopic combined intrarenal surgery

OBJECTIVES

There is a lack of data on the number of surgeries required for endoscopic combined intrarenal surgery (ECIRS). Accordingly, we aimed to identify the learning curve for ECIRS performed by multiple surgeons.

METHODS

We included 296 patients who underwent ECIRS at our university hospital between 2016 and 2021. A learning curve for percutaneous nephrolithotomy side was calculated considering urology-resident surgeons. The learning curve was retrospectively analyzed for surgical time, renal puncture time, stone-free rate, and complications and corrected for age, body mass index, stone size, computed tomography value, cumulative number of surgeries, and stone location.

RESULTS

This study included cases performed by 32 surgeons, including 30 residents and 2 attending surgeons. The median number of surgeries performed by the residents and attending surgeons prior to this study was 4.5 and 90, respectively. The median number of surgical procedures performed during the training period was seven. The surgical time of the residents decreased as the number of cases increased, reaching a median surgical time of 111 min for the attending surgeons after 16.4 cases. Renal puncture time was achieved in 20.1 cases. Complications related to renal access were observed in 13.0% (34 patients), Clavien-Dindo grade II in 1.9% (5 patients), and grade III or higher in 0.8% (2 patients). Comparing the first to fifth cases with the 21st and subsequent cases, the complication rate improved from 35% to 13%.

CONCLUSION

Our study demonstrated that ECIRS training provided 16-20 cases with a learning curve to achieve acceptable surgical outcomes.

Risk factors of stone residual after retrograde intrarenal surgery: A prospective cohort study

BACKGROUND

Complete removal of renal stones is crucial for optimal patient outcomes, but recent studies have reported residual stones after retrograde intrarenal surgery (RIRS). This study aimed to identify the associated risk factors to improve patient management and treatment selection.

METHODS

This cohort study was conducted over 18 months at two hospitals and recruited adult patients with renal stones less than 3 cm. Preoperative assessment included medical history, physical examination, laboratory tests, and radiological imaging. Intraoperative and postoperative data collection and follow-up were conducted to evaluate surgical success and potential complications.

RESULTS

A total of 100 patients were included, with a mean age of 45.3 ± 10.7 years and a mean BMI of 26.2 ± 1.4 kg/m2. Approximately 19% of the patients had residual stones after the RIRS procedure. The RUSS score showed good diagnostic performance with an AUC of 0.843, and the optimal cut point was ⩾2.0 with a sensitivity of 52.6% and specificity of 95.1%. Independent predictors of residual stones were multiple sites (OR = 24.98; p = 0.002), multiple stones (OR = 13.62, p = 0.002), stone size of 21-30 mm (OR = 4.91, p = 0.038), lower calyx site (OR = 4.85, p = 0.033), and surgeon experience of fewer than 50 cases (OR = 6.82, p = 0.020).

CONCLUSIONS

This study identifies several factors associated with residual stones after RIRS for renal stones, including stone size, location, number, and surgeon experience. The study suggests that the RUSS score can be used as a reliable tool for predicting the likelihood of residual stones, which can help clinicians in patient selection and treatment planning.

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.

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.

Novel scoring system combined with a virtual reality technique for the preoperative evaluation of the stone-free status after flexible ureteroscopy: the H.L.P.E.S. score

OBJECTIVE

The original S.O.L.V.E. scoring system was modified using virtual reality technology, and a new H.L.P.E.S scoring system was constructed to improve the accuracy of predicting the stone-free rate after flexible ureteroscopy.

METHODS

We retrospectively analyzed clinical and virtual reality data of 150 patients with renal calculi who underwent flexible ureteroscopy at the First Affiliated Hospital of Chongqing Medical University, Chongqing, China, from September 2019 to January 2022. Factors affecting the stone-free rate were evaluated in univariate and multiple logical regression analyses. Factors were divided by cut-off value under the receiver-operating characteristic curve and scored accordingly to a well-known international scoring system. Area under the curve predicted the stone-free rate. The accuracy and superiority of the stone-free rate after flexible ureterorenoscopy was compared between this scoring system and the S.O.L.V.E, R.I.R.S, T.O.HO, and RUSS scores.

RESULTS

Multiple logistic regression showed that the stone surface area, renal pelvis volume, and length of the calyces funnel were correlated with stone-free rate (P < 0.01, P = 0.021, P = 0.019, respectively). The H.L.P.E.S. score included stone surface area (1-2 points), renal pelvis volume (1-2 points), length of calyces funnel (1-2 points), pelvic calyceal height (1-2 points), and essence of stone (1-2 points). The area under the receiver-operating characteristic curve of H.L.P.E.S. score was 0.927, which was higher than the S.O.L.V.E., R.I.R.S., T.O.HO, and RUSS scores.

CONCLUSION

H.L.P.E.S. scoring can effectively predict the stone-free rate after flexible ureteroscopy for renal calculi and is superior to other scoring systems.

Efficacy of Flexible Ureteroscopic Lithotripsy and Percutaneous Nephrolithotomy in the Treatment of Complex Upper Urinary Tract Nephrolithiasis

Objective

A case-control study was conducted to compare the efficacy and prognostic factors of flexible ureteroscopic lithotripsy (FURL) and percutaneous nephrolithotomy (PCNL) when treating complex upper urinary tract renal calculi based on a retrospective cohort study.

Methods

The study period was from October 2019 to December 2021. A retrospective study was carried out on 100 patients with complicated upper urinary tract nephrolithiasis who underwent surgery in the Urology Department of our hospital. They were assigned into two groups: FURL and PCNL groups. The intraoperative blood loss, operation time, hematuria duration, hospital stay, primary stone removal rate, incidence of intraoperative and postoperative complications, VAS score, level of inflammatory factors, and micturition function were compared. According to the postoperative prognosis, the patients were reassigned into two groups: good prognosis group (n = 38) and poor prognosis group (n = 106). The factors related to poor prognosis after FURL and PCNL were screened, and multivariate loglistic regression analysis was adopted to determine the risk factors.

Results

The primary stone clearance rate in the PCNL group was significantly higher than that in the FURL group, and there was no significant difference in the incidence of intraoperative and postoperative complications between the two groups (P > 0.05). The intraoperative blood loss and the duration of hematuria in the PCNL group were significantly shorter than those in the FURL group, and the operation time and postoperative hospital stay in the FURL group were longer than those in the FURL group. The postoperative VAS score in the study group was significantly lower than that in the control group (P < 0.05). The levels of CRP, IL-1, TNF-α, and NF-κB in both groups decreased after operation, and the level of inflammatory factors in the PCNL group was significantly lower than that in the FURL group (P < 0.05). The indexes of IPSS and Q max in the PCNL group were significantly lower than those in the control group 3 months after operation. The index of micturition function in the PCNL group was significantly lower than that in the FURL group. Preoperative use of immunosuppressant, preoperative stone fever, positive preoperative urine culture, preoperative urinary leukocyte count ≥ 544 × L, intraoperative urinary opacity, and pus fur were significantly correlated with poor prognosis of ureteral patients (P < 0.05). Preoperative stone fever, high preoperative urinary leukocyte count, intraoperative urinary turbidity, and suppurative fur were independent risk factors for postoperative SIRS in patients with ureteral calculi.

Conclusion

PCNL is effective when treating complex upper urinary tract renal calculi. Compared with FURL, PCNL can remarkably reduce intraoperative blood loss and hematuria duration, can enhance micturition function, and will not remarkably increase the incidence of intraoperative and postoperative complications, high safety. High white blood cell count in urine before operation, fever due to stone before operation, turbid urine, and purulent fur during operation are independent risk factors for postoperative adverse outcome in patients with complex upper urinary tract renal calculi. Patients should be fully treated before 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.

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.

Rising prevalence of renal calculi: Treatments and considerations

ABSTRACT

Severe pain and urinary tract obstruction are hallmarks of renal calculi often requiring hospitalization and treatment. Renal damage can occur without proper intervention. This article discusses the role of nurses in caring for patients with renal calculi, current treatment approaches, and prevention strategies.

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.

Efficacy and Safety of External Physical Vibration Lithecbole After Extracorporeal Shock Wave Lithotripsy or Retrograde Intrarenal Surgery for Urinary Stone: A Systematic Review and Meta-analysis

Introduction: The current study evaluated the efficacy and safety of external physical vibration lithecbole (EPVL) after extracorporeal shock wave lithotripsy (SWL) or retrograde intrarenal surgery (RIRS) for urolithiasis. Methods: Publicized literature was systematically searched from EMBASE, Cochrane Library, PubMed, ScienceDirect, ClinicalTrials.gov, and Web of Science up to February 2020. Fixed-effects or random-effects model was chosen in risk ratio (RR) calculation according to heterogeneity. Quality of evidence was estimated under the guidance of Cochrane handbook. Stone expulsion rate, stone-free rates (SFRs), and complication rates were set as end points. Results: Six randomized controlled trials, including 853 patients, were eligible for analysis. EPVL significantly increased SFR within 3 weeks (RR = 1.17, 95% CI: 1.06-1.29, P = 0.001) and above 3 weeks (RR = 1.19, 95% CI: 1.03-1.37, P = 0.02) after SWL. EPVL also improved SFR within 3 weeks (RR = 1.84, 95% CI: 1.35-2.49, P < 0.0001) and above 3 weeks (RR = 1.53, 95% CI: 1.33-1.77, P < 0.00001) after RIRS. Besides, EPVL can significantly increase SFRs for stones in renal pelvis, lower calix, and multiple locations (all P-value <0.05). Although the overall complication rate was not significantly higher in EPVL + RIRS group, it was found to be 1.38 times higher in EPVL+SWL group (RR = 1.38, 95% CI: 1.06-1.79, P = 0.02), especially the incidence of flank pain (RR = 3.11, 95% CI: 1.02-9.46, P = 0.05). Conclusions: EPVL is effective and safe with high SFRs (especially in renal pelvis, lower calix, and multiple locations) after SWL or RIRS and lower overall complication rate after RIRS in patients with urolithiasis. However, the overall complication rate (especially the incidence of flank pain) was higher after EPVL + SWL.

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.