Influence of pre-stenting on RIRS outcomes. Inferences from patients of the Global Multicentre Flexible Ureteroscopy Outcome Registry (FLEXOR).

BACKGROUND: Retrograde Intrarenal Surgery (RIRS) is recommended as an alternative to percutaneous nephrolithotomy for stones up to 2 cm. Pre-stenting before RIRS remains controversial with various studies differing in outcomes and recommendations. We aim to understand how pre-stenting influences surgical outcomes. METHODS: A number of 6579 patients from the TOWER group registry were divided into pre-stented (group 1) and non-pre-stented groups (group 2). Patients aged ≥18 years old, with normal calyceal anatomy were enrolled. Patients with ureteric stones, anomalous kidneys, bilateral stones, planned for ECIRS were excluded. RESULTS: Patients are homogeneously distributed in both groups (3112 vs. 3467). The predominant indication for pre-stenting was symptom relief. Overall stone size was comparable, whilst group 1 had a significantly more multiple (1419 vs. 1283, P<0.001) and lower-pole (LP) stones (1503 vs. 1411, P<0.001). The mean operative time for group 2 was significantly longer (68.17 vs. 58.92, P<0.001). Stone size, LP stones, age, recurrence and multiple stones are contributing factors for residual fragments at the multivariable analysis. The incidence of postoperative day 1 fever and sepsis was significantly higher in group 2, indicating that pre-stenting is associated with a lower risk of post-RIRS infection and a lower overall complications rate (13.62% vs. 15.89%) (P<0.001). CONCLUSIONS: RIRS without pre-stenting can be considered safe without significant morbidity. Multiple, lower-pole and large stone is a significant contributor towards residual fragments. Patients who were not pre-stented had significantly higher but low-grade complications, especially for lower pole and large volume stones. While we do not advocate routine pre-stenting, a tailored approach for these patients should include proper counselling regarding pre-stenting.

Indications, preferences, global practice patterns and outcomes in retrograde intrarenal surgery (RIRS) for renal stones in adults: results from a multicenter database of 6669 patients of the global FLEXible ureteroscopy Outcomes Registry (FLEXOR).

PURPOSE: To collect a multicentric database on behalf of TOWER research group to assess practice patterns and outcomes of retrograde intrarenal surgery (RIRS) for kidney stones. METHODS: Inclusion criteria: age ≥ 18 years, normal renal/calyceal system anatomy, calculi of any size, number, and position. STUDY PERIOD: January 2018 and August 2021. Stone-free status: absence of fragments > 2 mm, assessed post procedure according to the local protocol (KUB X-Ray and/or ultrasound or non-contrast CT scan). RESULTS: Twenty centers from fifteen countries enrolled 6669 patients. There were 4407 (66.2%) men. Mean age was 49.3 ± 15.59 years. Pain was the most frequent symptom indication for intervention (62.6%). 679 (10.2%) patients underwent RIRS for an incidental finding of stones. 2732 (41.0%) patients had multiple stones. Mean stone size was 10.04 ± 6.84 mm. A reusable flexible ureteroscope was used in 4803 (72.0%) procedures. A sheath-less RIRS was performed in 454 (6.8%) cases. Holmium:YAG laser was used in 4878 (73.1%) cases. A combination of dusting and fragmentation was the most common lithotripsy mode performed (64.3%). Mean operation time was 62.40 ± 17.76 min. 119 (1.8%) patients had an intraoperative injury of the ureter due to UAS insertion. Mean postoperative stay was 3.62 ± 3.47 days. At least one postoperative complication occurred in 535 (8.0%) patients. Sepsis requiring intensive care admission occurred in 84 (1.3%) patients. Residual fragments were detected in 1445 (21.7%) patients. Among the latter, 744 (51.5%) patients required a further intervention. CONCLUSION: Our database contributes real-world data to support to a better understanding of modern RIRS practice and outcomes.

Propensity score-matched analysis comparing retrograde intrarenal surgery with percutaneous nephrolithotomy in anomalous kidneys.

BACKGROUND: Endourologic interventions for urolithiasis in patients with anomalous kidneys can be challenging, and comparisons between these interventions are not well studied. We aim to compare the safety, outcomes and complications of retrograde intrarenal surgery (RIRS) versus percutaneous nephrolithotomy (PCNL) in patients with urolithiasis in anomalous kidneys. METHODS: A propensity score-matched pair analysis (PSM) was performed on pooled patient data from 20 centers. 569 patients with anomalous kidneys (horseshoe kidney [HSK], ectopic kidney, malrotated kidney) and urolithiasis who received either PCNL or RIRS as the primary modality of intervention from 2010 to 2020 were analyzed. Patients were matched based on calculated propensity scores by a regression model using age, sex, comorbidities, stone size, and renal anomaly type as co-variates. Multivariate logistic regression of factors (mode of treatment [PCNL or RIRS], comorbidities, stone size) and their effects on outcomes of stone-free rate (SFR), need to abandon surgery due to intraoperative difficulty, postoperative hematuria and sepsis and were analyzed when applicable. RESULTS: After PSM, there were a total of 127 pairs in each group. Overall, PCNL conferred a higher SFR compared to RIRS (OR=3.69, 95% CI 1.91-7.46, P<0.001), particularly in HSK (OR=3.33, 95% CI 1.22-9.99, P=0.023), and ectopic kidneys (OR=18.10, 95% CI 3.62-147.63, P=0.002), with no significant difference in malrotated kidneys. There was no significant difference in postoperative sepsis observed. Surgery was abandoned more often in RIRS than PCNL (6.3% vs. 0%, P=0.014). Although PSM provides a robust analysis due to baseline differences in the unmatched cohorts, this study was limited by an inevitable degree of selection bias. CONCLUSIONS: While both modalities are safe and efficacious, PCNL yields better SFR than RIRS in patients with anomalous kidneys, with no difference in postoperative sepsis rates. Patients may benefit from personalized management best carried out in high volume endourology centers.

Role and Importance of Ergonomics in Retrograde Intrarenal Surgery: Outcomes of a Narrative Review.

Background: With recent technological advancement, new and improved endoscopic instruments and laser devices have catapulted flexible ureteroscopy to the forefront, hence making retrograde intrarenal surgery (RIRS) a popular choice for the management of renal stones. However, RIRS has also resulted in an increasing number of work-related musculoskeletal disorders, which can have a detrimental impact on surgeons' physical health and operative lifespan. The aim of our review is to examine the impact and feasibility of ergonomic adjustments and outline future directions and recommendations to improve the awareness of and reduce the prevalence of musculoskeletal injuries among urologists. Methods: This study was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A thorough literature review was conducted of several databases using the following keywords and Medical Subject Headings (MeSH) terms to generate a search strategy: nephrolithiasis, kidney calculus, renal calculus, staghorn calculus, ergonomics, position, fatigue, comfort, tire, physical strain, visual strain, muscle, ureteroscopy, RIRS, laser, and lithotripsy. Studies were chosen for inclusion by reviewers independently, and the data were consolidated for analysis. Results: A total of 1446 articles were identified on initial literature search; 23 were included in the final analysis. The impact of various ergonomic modifications on operative outcomes, surgeons, surgical equipment, and patients, was analyzed. In addition, we summarized all the improvements that resulted in better ergonomics in RIRS. Conclusion: Ergonomics in RIRS is poorly understood and there are currently no formal guidelines for this aspect. While modern endourology armamentarium seems to help with procedural ergonomics, more needs to be done to enhance surgeon comfort, protect surgeon longevity, and prioritize the health and safety of endourologists.

Comparison of silicone versus polyurethane ureteral stents: a prospective controlled study.

BACKGROUND: Approximately 80% of patients with indwelling ureteral stents experience stent related symptoms (SRS). We believe SRS can be reduced through altering the composition of ureteral stents to a less firm material. Therefore, we aim to compare modern silicone and polyurethane ureteral stents in terms of SRS intensity and safety. METHODS: From June 2018 to October 2018, patients from two distinct clinical centers were prospectively enrolled in the study and stratified (non-randomly) into either control group A, patients who received polyurethane stents (Rüsch, Teleflex), or experimental group B, patients who received silicone stents (Cook Medical). Each participant completed a survey 1 h after stent insertion, in the middle of the stent dwelling period, and before stent removal or ureteroscopy noting body pain and overactive bladder via the visual analog scale pain (VASP) and overactive bladder (OAB) awareness tool, respectively. Additionally, successfulness of stent placement, hematuria, number of unplanned visits, and stent encrustation rates were assessed within each group. RESULTS: A total of 50 patients participated in the study, control group A consisted of 20 patients and experimental group B consisted of 30 patients. Participants in group B, silicone ureteral stents, demonstrated significantly lower mean values of VASP 2 weeks prior to stent removal and promptly before stent removal (p = 0.023 and p = 0.014, respectively). No other comparisons between the two groups were statistically significant. CONCLUSIONS: Compared to polyurethane ureteral stents, silicone ureteral stents are associated with lower body pain intensity assessed by VASP 2 weeks before stent removal and at the time of stent removal. TRIAL REGISTRATION: Current Controlled Trials NCT04000178. Retrospectively registered on June 26, 2019.

Novel Approach for Endoscopic Management of Duodenal Injury during Perirenal Infected Haematoma Drainage after Shock-Wave Lithotripsy.

Background. Gaining percutaneous access during percutaneous nephrolithotomy (PNL) can be complicated with the bowel injury. We report a novel approach of management of duodenal injury complicating percutaneous drainage of infected haematoma after Shock-Wave Lithotripsy (SWL). Case Presentation. A 57-year-old patient with the 15 mm right pelvic kidney stone underwent uneventful SWL. Patient visited emergency department 3 days later with high fever and chills with severe right flank pain. CT urography revealed lower pole kidney injury with signs of infected hematoma due to low attenuation areas but without signs of obstruction or urine leakage. Infected haematoma was drained percutaneously under ultrasound and X-ray control and a pigtail catheter 10 Fr was left beneath the lower pole of the right kidney. Postoperatively duodenal injury was suspected due to amber color, low creatinine, and high bilirubin level in the drainage output. CT demonstrated that the pigtail of the drain had entered the second part of the duodenum. Catheter was withdrawn and defect of the duodenal wall was stapled with four staples endoscopically. After 2 days of fasting patient was allowed to start oral food intake and was discharged on the 5th day. Conclusion. Injury of the duodenum during percutaneous kidney manipulation is an extremely rare complication. Conservative management consisting of endoscopic stapling of the duodenal wall defect is a safe and feasible approach to expediting the recovery of the patient.