Impact of preoperative ureteral stenting on stone-free rates of ureteroscopy for nephroureterolithiasis: a matched-paired analysis of 286 patients

The impact of preoperative ureteral stent duration on retrograde intrarenal surgery results: a RIRSearch group study

A JJ stent placed before retrograde intrarenal surgery (RIRS) may ease the procedure. However, it is important to note that a prolonged duration of double J stent (DJS) placement before RIRS may increase the risk of postoperative urinary tract infection (UTI). Various publications have established this association, although the duration of the DJS before surgery is scarce. Our study investigates the relationship between the pre-stenting period and postoperative UTI and establishes a cut-off period to minimize this risk. We included a total of 500 cases with preoperative DJS prior to RIRS. The patients were divided into five groups according to their preoperative stenting duration (Group 1: 0-15 days; Group 2: 16-30 days; Group 3: 31-45 days; Group 4: 46-60 days; Group 5: >60 days). Demographic and clinical data of the patients, stone properties, operation data, perioperative and postoperative complications (including fever and UTI), hospitalization time, and stone-free rates (SFR) were compared. The groups contained 53, 124, 102, 63, and 158 patients. The demographics of the patients in each group were similar. There was no statistically significant difference between DJS duration, perioperative/postoperative complications, and SFR, except for the ureteral access sheath (UAS) insertion rate. (p = 0.001). The postoperative fever/UTI rate was the lowest in Group 1 (p = 0.046) compared to other durations. Stent duration does not impact SFR. Longer stents enhance UAS insertion success but increase postoperative infection risk. Our results suggest that RIRS should be performed within two weeks, ideally 20 days following stent insertion, to minimize postoperative infection risk.

Factors associated with unplanned clinical encounters for ureteral stent-related symptoms

BACKGROUND, INTRODUCTION AND AIM

Ureteral stent-related symptoms (USRS) often result in unplanned phone calls and ER visits. We hypothesize that patient factors can be identified to predict these unplanned encounters.

METHODS AND MATERIALS

Retrospective analysis of indwelling ureteral stent placements from 2014 to 2019 at a single institution by CPT code was performed. Patient demographics, discharge medications, and clinical factors were evaluated using multiple logistic regression with respect to postoperative telephone and emergency room (ER) encounters for USRS.

RESULTS

Of 374 patients, 75 (20.1%) had one or more encounters for USRS: 48 (12.8%) called the clinic and 39 (10.4%) returned to the ER. Chronic opioid use was predictive of calls to clinic and ER visits (OR 3.21 [CI 1.42-6.97], p < 0.01 and OR 3.64 [CI 1.45-8.98], p < 0.01). Survival analysis stratified by history of chronic opioid use and discharge opioid prescriptions demonstrated that opioid naïve patients receiving opioids at discharge had unplanned encounters sooner and more often [Calls p = 0.025, ER p = 0.041]), whereas patients with chronic opioid use returned to the ER sooner and more frequently when prescribed additional opioids (Calls p = 0.4, ER p = 0.002).

CONCLUSION

Patients with a history of chronic opioid use may experience more intense USRS or have a lower threshold to seek medical care than opioid naïve patients and tend to bypass calling the clinic for the ER. Given that none of the studied medications reduced unplanned patient contact for USRS, urologists should consider upfront definitive management of urinary obstruction when appropriate.

Effect of preoperative ureteral stenting on the surgical outcomes of patients with 1-2 cm renal stones managed by retrograde intrarenal surgery using a ureteral access sheath

OBJECTIVE

To assess the surgical results of patients who underwent retrograde intrarenal surgery (RIRS) using a ureteral access sheath (UAS) for management of renal stones sized 1-2 cm compared between patients who did and did not undergo preoperative ureteral stenting.

MATERIALS AND METHODS

This prospective study included 83 patients (aged ≥ 20 years) who underwent RIRS from July 2021 to January 2023. All patients had renal calculi (stone size: 1-2 cm) located within the pelvicalyceal system. 43 and 40 patients were allocated to the non-prestent (group A) and prestent (group B), respectively. Patient baseline characteristics, renal stone details, operative data, stone-free rate (SFR) at 4 weeks and 6 months, and perioperative complications were compared between groups.

RESULTS

The baseline characteristics of all patients were comparable across the groups. Four weeks after surgery, the overall stone-free rate (SFR) stood at 62.65%. In the non-prestent and prestent groups, the SFRs were 58.12% and 67.5%, respectively (p = 0.89). By the sixth month post-surgery, the overall SFR rose to 80.72%. In the non-prestent and prestent groups, the SFRs were 76.74% and 85%, respectively (p = 0.081). No notable differences emerged in other variables, including perioperative complications, between the two groups.

CONCLUSIONS

The SFR showed no significant difference between the prestenting and non-prestenting groups at the 4-week and 6-month postoperative marks. Additionally, there were no substantial differences in complications during surgery and recovery between the groups. Notably, the SFR increased from 4 weeks to 6 months without any additional procedures in either group.

Comparison of immediate versus post-stenting ureteroscopy for ureteral stones treatment

Ureteroscopy is a highly effective treatment for ureteral stones, characterized by a high stone-free rate and a low need for re-treatment. Ureteral stent placement can improve the insertion of the ureteral access sheath and ureteroscope but may be associated with higher morbidity prior to and after ureteroscopy. The study aimed to compare immediate versus post-stenting ureteroscopy for ureteral stone treatment in terms of operative time, intra- and post-operative complications, length of hospital stay, and stone-free rate. This prospective study involved 126 patients with ureteral stones divided into two groups: the post-stenting ureteroscopy group (PS-URS), who underwent primary ureteral stenting by double J followed by delayed ureteroscopy, and the immediate ureteroscopy group (I-URS), who underwent immediate ureteroscopy without previous stenting. Sixty-six patients were included in the PS-URS group and 60 patients in the I-URS group. Results were comparable, with no significant differences between both groups. The mean operative time was 33.77±3.51 minutes for the PS-URS group and 34.60±2.01 minutes for the I-URS group. The average length of hospital stay was 0.84±2.55 days for PS-URS and 0.92±1.96 days for I-URS patients. The stone-free rate was 97% in the PS-URS group and 95% in the I-URS group. The overall complication rate was 4.5% versus 5% in the PS-URS and I-URS groups, respectively, with all complications being minor and managed effectively. Immediate ureteroscopy is a safe and relevant operative approach for ureteral stones, with comparative results for post-stenting delayed ureteroscopy.

Primary Ureteroscopy without Pre-Stenting for Proximal Ureteral Stones-Is It Feasible?

BACKGROUND

Primary ureteroscopy with laser lithotripsy is the treatment of choice for distal ureteral stones. However, in cases of proximal ureteral stones, some urologists recommend the preliminary insertion of a ureteral stent and deferred ureteroscopy. We aimed to evaluate the necessity of preliminary ureteral stent insertion in the management of proximal ureteral stones by comparing the surgical outcomes of patients undergoing primary ureteroscopy with laser lithotripsy for proximal vs. distal ureteral stones.

METHODS

Medical records of patients who underwent ureteroscopy between 2016 and 2017 in our institution were retrospectively reviewed. Data collected included demographic data, stone size, renal function, intra- and post-operative complications, and stone-free rate (SFR). Patients were divided into two groups: proximal ureteral stones and distal ureteral stones.

RESULTS

The cohort included 241 patients who underwent ureteroscopy. Among them, 106 had a proximal ureteral stone. The median age was 51 (IQR 41-65) years. Patients who underwent ureteroscopy for proximal ureteral stones were significantly older (p = 0.007). The median stone's maximal diameter was 7 (5-10) mm. The complication rate and stone-free rate (SFR) were similar in both groups (p = 0.657 and p = 1, respectively). The prevalence of post-procedural ureteral stent insertion was higher among patients who underwent ureteroscopy for proximal ureteral stones: 92.5% vs. 79.3% (p = 0.004).

CONCLUSIONS

Our study concludes that primary ureteroscopy with laser lithotripsy for proximal ureteral stones is a valid and feasible treatment with a similar surgical outcome compared to distal ureteral stones. Preliminary ureteral stent insertion seems to be unnecessary.

Surgical outcomes of patients who underwent retrograde intrarenal surgery using a ureteral access sheath to manage kidney stones sized 1-2 cm compared between patients who did and did not undergo preoperative ureteral stenting

Objective

To investigate the surgical outcomes of patients who underwent retrograde intrarenal surgery (RIRS) using a ureteral access sheath (UAS) to manage kidney stones sized 1-2 cm compared between patients who did and did not undergo preoperative ureteral prestenting.

Materials and methods

This retrospective cohort study included 166 patients (aged ≥18 years) who underwent RIRS at Siriraj Hospital (Bangkok, Thailand) during February 2015-February 2020. All patients had renal calculi (stone size: 1-2 cm) located within the pelvicalyceal system. 80 and 86 patients were allocated to the prestent and non-prestent groups, respectively. Patient baseline characteristics, renal stone details, operative equipment, stone-free rate (SFR) at 2 weeks and 6 months, and perioperative complications were compared between groups.

Results

All patient baseline characteristics were similar between groups. At 2 weeks after surgery, the overall SFR was 65.1%, and the SFRs in the prestent and non-prestent groups were 73.4% and 59.5%, respectively (p = 0.09). At 6 months after surgery, the overall SFR was 80.1%, and the SFRs in the prestent and non-prestent groups were 90.7% and 79.3%, respectively (p = 0.08). The incidence of perioperative complications was not significantly different between groups.

Conclusions

There was no significant difference in the SFR between the presenting and non-prestenting groups at both the 2-week and 6-month postoperative time points. There was also no significant difference in intraoperative and postoperative complications between groups. The SFR was higher at 6 months than at 2 weeks in both groups with no additional procedure.

Delays in Ureteroscopy and Shockwave Lithotripsy After Ureteral Stent Placement: Impact on Infectious Complications, Resource Use, and Medical Costs

Purpose: To evaluate the effects of ureteral stent duration before ureteroscopy (URS) or extracorporeal shockwave lithotripsy (SWL) on infectious complications, health care resource utilization (HCRU), and costs. Materials and Methods: Patients who underwent URS/SWL within 6months of ureteral stent placement were identified from commercial claims, categorized by time from stent placement to URS (0-15, 16-30, 31-60, and >60 days) or SWL (0-15, 16-30, and >30 days), and followed 1-month postprocedure. The relationship between ureteral stent duration and emergency department (ED) visits, inpatient admissions, infectious complications (pyelonephritis/sepsis), imaging, and costs was evaluated. Results: Mean time to URS (n = 9276 patients) was 21.3 ± 24.4 days and SWL (n = 4689 patients) was 19.0 ± 24.8 days. Compared with patients who underwent URS within 15 days of ureteral stent placement, URS 31 to 60 days after ureteral stent placement was significantly associated with inpatient admissions (odds ratio [OR] 2.56, 95% confidence interval [CI] 2.03-3.22); infectious complications (OR 2.82, 95% CI 2.09-3.81); imaging (OR 2.12, 95% CI 1.82-2.46); and medical costs (OR 1.49, 95% CI 1.40-1.58). Compared with patients who underwent SWL within 15 days of ureteral stent placement, SWL more than 30 days after ureteral stent placement was significantly associated with ED visits (OR 1.79, 95% CI 1.37-2.34); inpatient admissions (OR 3.34, 95% CI 2.38-4.69); infectious complications (OR 3.54, 95% CI 2.20-5.70); imaging (OR 2.65, 95% CI 2.23-3.15); and medical costs (OR 1.45, 95% CI 1.36-1.54). Conclusions: URS or SWL >30 days after ureteral stent placement increased the likelihood of infectious complications, HCRU, and medical costs.

Impact of Preoperative Ureteral Stenting in Retrograde Intrarenal Surgery for Urolithiasis

Background and Objectives: Ureteral stent insertion passively dilates the ureter. Therefore, it is sometimes used preoperatively before flexible ureterorenoscopy to make the ureter more accessible and facilitate urolithiasis passage, especially when ureteroscopic access has failed or when the ureter is expected to be tight. However, it may cause stent-related discomfort and complications. This study aimed to assess the effect of ureteral stenting prior to retrograde intrarenal surgery (RIRS). Materials and Methods: Data from patients who underwent unilateral RIRS for renal stone with the use of a ureteral access sheath from January 2016 to May 2019 were retrospectively analyzed. Patient characteristics, including age, sex, BMI, presence of hydronephrosis, and treated side, were recorded. Stone characteristics in terms of maximal stone length, modified Seoul National University Renal Stone Complexity score, and stone composition were evaluated. Surgical outcomes, including operative time, complication rate, and stone-free rate, were compared between two groups divided by whether preoperative stenting was performed. Results: Of the 260 patients enrolled in this study, 106 patients had no preoperative stenting (stentless group), and 154 patients had stenting (stenting group). Patient characteristics except for the presence of hydronephrosis and stone composition were not statistically different between the two groups. In surgical outcomes, the stone-free rate was not statistically different between the two groups (p = 0.901); however, the operation time for the stenting group was longer than that of the stentless group (44.8 ± 24.2 vs. 36.1 ± 17.6 min; p = 0.001). There were no differences in the complication rate between the two groups (p = 0.523). Conclusions: Among surgical outcomes for RIRS with a ureteral access sheath, preoperative ureteral stenting does not provide a significant advantage over non-stenting with respect to the stone-free rate and complication rate.

Predicting failed access in unstented ureteroscopy

The risk of failed access (FA) in unstented ureteroscopy ranges from 7.7 to 16%, with young females and those with prior ipsilateral stone surgery, narrow ureteral anatomy, and proximal ureteral stone location carrying higher risk. We aim to determine the rate of failed access at our institution and analyze demographic, clinical, and operative variables associated with FA. We conducted a review of all unstented ureteroscopy procedures at our institution between January 2018 and June 2022. Ureteroscopy for stone, stricture, and neoplasm were included. The primary endpoint was rate of FA, when the unstented ureter failed to accommodate the ureteroscope distal to the target lesion. Demographic, clinical, and operative variables were analyzed to determine if there was an association with FA. Of the 562 ureteroscopies cases reviewed, 221 unstented ureteroscopies fit our inclusion criteria. FA occurred in 34 (15.4%). Previous stone passage (p = 0.039) and distal ureteral location (p = 0.042) were associated with successful access (SA). Proximal ureteral location was associated with FA (p = 0.008). These variables remained statistically significant when analyzed with multivariable logistic regression. There was no association with other demographic, clinical and operative variables. FA occurred at a rate of 15.4% at our institution. Previous stone passage and distal ureteral location were associated with SA, while proximal ureteral location was associated with FA. Prospective studies are needed to better determine predictors of FA.

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.

Retrograde intrarenal surgery for lower pole stones utilizing stone displacement technique yields excellent results

Objective

To evaluate the long-term stone-free rate (SFR) of retrograde intra-renal surgery (RIRS) in the treatment of lower pole renal calculi using only basket relocation and identify independent predictors of stone-free status.

Methods

All consecutive patients undergoing RIRS lower pole renal calculi at a single high-volume tertiary center were analyzed retrospectively. Lower pole stones were relocated to the upper pole, where laser lithotripsy was performed. All patients were followed up in the clinic following the surgery and yearly thereafter. The stone-free status was assessed with a combination of an abdominal ultrasound and abdominal X-ray, or an abdominal non-contrast computed tomography if the stones were known to be radiolucent.

Results

A total of 480 consecutive patients who underwent RIRS for treatment of lower pole renal calculi, between January 2012 and December 2018, were analyzed from a prospectively maintained database of 3000 ureteroscopies. With a median follow-up time of 18.6 months, the mean SFR was 94.8%. The procedures were unsuccessful in 26 (5.4%) patients due to unreachable stones. The median stone size of the unreachable stones was 12 mm (range 10-30 mm). Multivariable logistic regression analysis revealed two predictors of SFR for lower pole stones: a small cumulative stone burden (odds ratio [OR]: 0.903, 95% confidence interval [CI]: 0.867-0.941, p<0.0001) and preoperative ureteral stent insertion (OR: 0.515, 95% CI: 0.318-0.835, p=0.007).

Conclusion

The long-term SFR of RIRS for the treatment of lower pole stones with basket displacement with appropriate patient selection is high.

Role of pre-operative ureteral stent on outcomes of retrograde intra-renal surgery (RIRS): systematic review and meta-analysis of 3831 patients and comparison of Asian and non-Asian cohorts

PURPOSE

To evaluate the outcomes of pre-stented (PS) versus non-pre-stented (NPS) patients who have undergone retrograde intrarenal surgery (RIRS) for renal calculi with subgroup analysis of Asian and non-Asian cohorts.

METHODS

Protocol is registered in PROSPERO, CRD42021261123. Eligible studies identified from four electronic databases. Meta-analysis was done to enumerate the outcomes of RIRS in between PS and NPS. Secondary sub-analysis was done to look for differences in outcomes in Asian and non-Asian cohorts.

RESULTS

Fourteen studies involving 3831 patients (4 prospective, 10 retrospective studies) were included. PS patients experienced higher success rates of ureteral access sheath (UAS) insertion than NPS (RR 1.09, 95% CI 1.05-1.13, p < 0.00001). PS patients had lower risk of ureteral injuries from UAS placement (RR 0.69, 95% CI 0.50-0.96, p = 0.03). No significant differences in intra- and postoperative complications between two groups were found. Stone-free rate (SFR) outcomes for residual fragment (RF) cut-off of < 1 mm and < 4 mm favoured the PS patients (RR 1.10, 95% CI 1.04-1.17, p = 0.002 for < 4 mm, RR1.10, 95% CI 1.02-1.19, p = 0.02 for < 1 mm). In the subgroup analysis, PS Asian patients had similar SFR as NPS patients for SFR(< 4 mm) but non-Asian population showed better outcomes in the PS patients for SFR(< 4 mm) (RR 1.31, 95% CI 1.13-1.52, p = 0.0005).

CONCLUSIONS

This meta-analysis suggests that pre-stenting results in a higher success for UAS placement, minimising intraoperative ureteric injury, with higher overall SFR for any RF cut-off in PS cohorts. In non-Asian cohort, significant differences occurred at SFR < 4 mm but not for SFR < 1 mm. No difference was seen in our Asian cohort for any SFR cut-off in both PS and NPS patients.

The impact of preoperative percutaneous nephrostomy as a treatment strategy before flexible ureteroscopy for impacted upper ureteral stones with hydronephrosis

Background

The treatment of impacted upper ureteral stones with hydronephrosis remains a challenge for urologists. The current study aimed to evaluate the impact of preoperative percutaneous nephrostomy (PNS) as a treatment strategy before flexible ureteroscopy (f-URS) of asymptomatic impacted upper ureteral stones with hydronephrosis.

Methods

This multicenter retrospective study included patients who underwent PNS (group A, n=61) and those who did not (group B, n=75) before f-URS for asymptomatic impacted upper ureteral stones with hydronephrosis. Impacted ureteral stones are defined as those that remain in one position for >2 months. Operative outcomes, including stone-free rate, operation time, postoperative hospital days, and complication rate, were evaluated.

Results

There were no significant differences in age, sex, and stone size between the two groups except in the grade of hydronephrosis, with group A having more cases of advanced hydronephrosis than group B. The stone-free rate was significantly higher in group A than in group B [95% vs. 77% (P=0.004)]. However, there were no significant differences between the groups in operation time [55 vs. 55 min (P=0.84)], postoperative fever [5% vs. 5% (P=1.00)], and postoperative hospital days [2 vs. 2 days (P=0.44)]. In group A, preoperative PNS placement was performed 4 days before f-URS, and the PNS was removed postoperatively on the same day of the f-URS. Additionally, subgroup analysis was performed in cases of grade 2 and 3 hydronephrosis. A total of 110 patients, 60 who underwent f-URS with PNS and 50 who underwent f-URS without PNS, were included. The stone-free rate was significantly higher in f-URS with PNS than in f-URS without PNS [95% vs. 76% (P=0.005)]. However, no significant differences were found between the groups in operation time, ureteral injury, postoperative fever, and postoperative hospital days.

Conclusions

At grade 2 or 3 hydronephrosis, preoperative PNS as a treatment strategy for a few days prior to f-URS for impacted upper ureteral stones improved the stone-free rate without increasing the operation time and postoperative length of hospital stay.

The Outcomes of Pre-Stenting on Renal and Ureteral Stones: A Meta-Analysis

BACKGROUND

Pre-stenting (PS) on the outcomes of semirigid and flexible ureteroscopic lithotripsy for a different upper urinary urolithiasis remains controversial. We performed a meta-analysis comparing the outcomes of ureteroscopic lithotripsy between PS and non-PS.

MATERIALS AND METHODS

Randomized, controlled trials and observational studies comparing PS and non-PS were identified from electronic databases. Stone-free rate (SFR), operative time, and complications were compared by qualitative and quantitative syntheses (meta-analyses).

RESULTS

Eleven articles were included in this study. Nearly, all of recently published studies exhibited relatively moderate or high quality during quality assessment. PS was more likely to achieve good SFR compared with non-PS (p < 0.00001). The subgroup results indicated that PS improved the SFR for renal stones and the stones dealt by flexible ureteroscopy (p = 0.0002; p < 0.0001, respectively; some ureteral stones were dealt by flexible ureteroscopy). Ureteral stones and the stones dealt by semirigid ureteroscopy were not influenced by PS (p = 0.62; p = 0.90, respectively). PS is equal as non-PS in terms of operative time for renal stones and the renal and ureteral stones dealt by flexible ureteroscopy (p = 0.47; p = 0.05). No significant difference was found in major complications between the 2 groups for total or for the subgroup of renal stones (p = 0.3; p = 0.69).

CONCLUSIONS

For ureteral stones or the stones dealt by semirigid ureteroscopy, PS does not show any benefits. For renal stones or the stones dealt by flexible ureteroscopy, PS improves the SFR and may be as safe as non-PS.

Endoscopic Ureteral Dilation Balloon Catheter for a Difficult Ureter: A New Novel Approach

OBJECTIVES

This study aims to assess the safety and efficacy of INNOVEXTM ureteral dilation balloon catheter to promote the likelihood of passing the ureter to complete primary ureteroscopy (URS).

METHODS

This was a prospective case series of patients during URS between August 2018 and January 2020 at the Pudong New District People's Hospital. A 12-Fr INNOVEXTM ureteral dilation balloon catheter was used to dilate the ureter when a 5° Wolf 6.0/7.5-Fr ureteroscope encounters an unpredictable hindrance to retrograde access for ureteral stones. Patients with documented ureteral strictures, radiation therapy, or urothelial cancer were excluded from the analysis. The primary outcomes were to characterize the use, safety, and efficacy of ureteral dilation balloon catheter to promote stone treatment during URS.

RESULTS

Eight hundred and sixty-two patients underwent primary URS of ureteral stones over the study period. The use of a ureteral dilation balloon catheter to promote ureteral access was performed in 65 (7.54%) cases and effectively allowed completion of the procedure in 58 (89.23%) cases. No ureteral perforation and access loss occurred during the operation. Seven patients required ureteral stent placement for passive ureteral dilation, with definitive stone treatment later. Postoperative radiographic follow-up was available for 63 (96.92%) cases, and no ureteral stenosis was observed after balloon dilation.

CONCLUSION

The use of a new ureteral dilation balloon catheter before endoscopic treatment of ureteral stones was associated with a high success rate and few complications. The convenient use method under direct vision at the whole process may increase the willingness of doctors to use it. In addition, it may reduce the need for secondary procedures for patients undergoing URS to manage ureteral stones.

Impact of Preoperative Stenting on the Outcome of Flexible Ureterorenoscopy for Upper Urinary Tract Urolithiasis: A Systematic Review and Meta-Analysis

PURPOSE

This study aimed to investigate the effect of preoperative stenting (POS) on the perioperative outcomes of flexible ureterorenoscopy (fURS).

MATERIALS AND METHODS

A systematic review and meta-analysis was conducted based on the PRISMA statement. From the initially retrieved 609 reports, we excluded the ineligible studies at 2 stages. We only included studies that contained fURS patients with and without POS in the same report. Data of patients who underwent semirigid ureteroscope only were excluded from the analysis. The Newcastle-Ottawa Scale (NOS) system was applied for risk of bias assessment.

RESULTS

A total of 20 studies including 5,852 patients were involved. 48.5% of the patients had preoperative stent. Stone-free rate was significantly higher with prestenting; odds ratio (OR) was 1.98 (95% CI: 1.51-2.58) (Z = 5.02; p = 0.00001). It also displayed tendency toward lower complications; OR was 0.74 (95% CI: 0.52-1.05) (Z = 1.67; p = 0.09). POS significantly increased the use of ureteral access sheath; OR was 1.49 (95% CI: 1.05-2.13) (Z = 2.22; p = 0.03). Risk of bias assessment showed 13 and 7 studies with low and moderate risk, respectively.

CONCLUSIONS

POS clearly improves the stone-free rates after fURS. It might reduce the complications, especially ureteral injury. These findings might help solve the current debate and can be useful for urologists during patient counselling for a proper decision-making.

Success rate of repeat flexible ureteroscopy following previous failed access: An analysis of stent duration

INTRODUCTION

Approximately 8% of patients that undergo therapeutic or diagnostic ureteroscopy will have the procedure aborted and ureter stented due to failed access. The primary objective of this study was to assess mean stent duration prior to repeat ureteroscopy and to calculate the associated successful access rate.

METHODS

This retrospective, descriptive study evaluated all patients undergoing interval ureteroscopy following a failed procedure by endourologic surgeons at the University of Alberta from 2016-2018. Patients declining interval ureteroscopy, or those with malignant/known ureteral strictures were excluded from the study. The primary outcome measures were median time to salvage ureteroscopy and the rate of successful access of the repeat procedure.

RESULTS

A total of 119 patients were identified as having a failed ureteroscopy during our study period. First-time and recurrent stone formers accounted for 64 (53.8%) and 47 (39.5%) patients, respectively. Median stent duration to second procedure was 17 days (average 20, range 10-84). Most patients had their repeat ureteroscopy at 14 days or greater (81.5%); 22 (18.5%) patients had their repeat ureteroscopy between 10 and 13 days. The success rate of a second ureteroscopy after stenting was 99.2% (118/119).

CONCLUSIONS

Ureteric stenting following failed ureteroscopy leads to exceedingly high rates of successful access at interval procedure (99.2%). The standard duration of ureteric stenting employed at our institution is two weeks. Of the patients that underwent an accelerated second procedure (between 10-13 days of stenting), all had successful access at their interval procedure.

Prestenting Versus Nonprestenting on the Outcomes of Flexible Ureteroscopy for Large Upper Urinary Stones: A Systematic Review and Meta-Analysis

INTRODUCTION

The purpose of this article is to evaluate the efficacy and safety of prestenting (PS) versus non-PS (NPS) of flexible ureteroscopy (fURS) to treat large upper urinary stones.

METHODS

We conducted a systematic literature research of PubMed, Ovid, Scopus (up to August 2019), and citation lists to identify eligible studies. All studies comparing PS versus NPS of fURS were included. Data were analyzed using the Cochrane Collaboration's Review Manager (RevMan) 5.3 software.

RESULTS

Overall, 7 studies including 3,145 patients (PS 1,408; NPS 1,737) were included in this article. PS group was associated with older age (weighted mean difference [WMD] 0.91 year; p < 0.001) and more male patients (odds ratio [OR] 1.34; p < 0.001). There were no statistical differences between PS and NPS in BMI (WMD 0.34 kg/m2; p = 0.13), stone size (WMD 0.13 mm; p = 0.77), and operative time (WMD 0.44 min; p = 0.86). Compared with NPS, PS showed better initial success rate (OR 4.04; p < 0.001) and higher SFR (OR 1.64; p < 0.001). There were no statistical differences for complications (OR 0.84; p = 0.42) and Clavien-Dindo score ≥3 complications (OR 1.04; p = 0.93).

CONCLUSION

PS could improve initial success rate and avoid secondary general anesthesia for first ureteral access sheath failed patients. PS could provide better SFR than NPS in the treatment of large upper urinary stones with fURS.

[Stone therapy-use and limitations of the guidelines]

Increase of medical knowledge, technical innovation together with a demographic change, and increase of stone incidence in daily practice challenges guideline preparation and clinical studies. Increasing interdisciplinary collaboration in stone treatment can also be demonstrated in the number of affiliated professional and working groups in the current guideline update. The following case illustrates treatment options in a symptomatic patient harbouring bilateral stones and metabolic risk factors. Decision guidance for treatment and recurrence prevention measures are presented on the basis of expert opinion and available published evidence.

The role of preoperative ureteral stenting in retrograde intrarenal surgery in renal stone patients: a propensity score-matched study

Background

The purpose of this study was to investigate the effect of preoperative ureteral stenting on retrograde intrarenal surgery (RIRS).

Methods

We retrospectively analyzed RIRS cases from October 2014 to June 2017. Patients were divided into two groups according to preoperative ureteral stent insertion. The characteristics of the patients [age, body mass index (BMI), sex, previous disease history, hemoglobin, creatinine, estimated glomerular filtration rate (eGFR)], characters of stone (size, number, density, location), ureteral access sheath (UAS) success rate, perioperative complication, operative time, hospitalization time, period with stent, postoperative urinary tract infection (UTI) rate, stone free rate (SFR), and additional treatment rate were analyzed.

Results

RIRS was performed for 122 patients. Seventy-three patients had preoperative ureteral stents before RIRS, while 49 patients did not have preoperative ureteral stents. The median size of the stone was 14.5 mm. Overall SFR was 87.7%. Preoperative eGFR was relatively high in patients who underwent preoperative stenting (68.18 vs. 79.01 mL/min/1.73 m², P=0.042). Preoperative stenting led to improvement in the success rate of UAS insertion (97.3% vs. 87.8%, P=0.038) during surgery. Before and after propensity score matching revealed a significant difference in operation time when the diameter of the stone was smaller than 1 cm (P=0.019 and P=0.004). However, there was no significant difference in operation time, postoperative UTI rate, additional treatment rate, or SFR.

Conclusions

Preoperative ureteral stenting can facilitate UAS insertion, and reduce operation time in RIRS for stones with a diameter less than 1 cm.

Targeting prostate cancer stem-like cells by an immunotherapeutic platform based on immunogenic peptide-sensitized dendritic cells-cytokine-induced killer cells

Background

Autologous cellular immunotherapy or immune enhancement therapy has demonstrated some promising benefits for prostate cancer. T cell-based immunotherapy or sipuleucel-T therapy has yielded certain beneficial responses and a slight improvement on the overall survival of patients with metastatic castration-resistant prostate cancer (mCRPC) as shown in some clinical trials, suggesting that prostate cancer is immunoresponsive.

Methods

In this study, we developed an adaptive cytokine-induced killer cell (CIK)-based immunotherapeutic application targeting the prostate cancer stem-like cells (PCSCs). In this therapeutic platform, dendritic cells (DC) were isolated from the peripheral blood mononuclear cells (PBMCs) and preloaded or sensitized with immunogenic peptides derived from two PCSC-associated cell membrane molecules, CD44 and EpCAM, followed by co-culture with the expanded peripheral blood lymphocyte (PBL)-derived CIK cells. The in vitro cytotoxic activity of DC-activated CIK cells against PCSCs was determined by CCK8 and TUNEL assays, and the in vivo anti-tumor effect of DC-activated CIK cells on prostate cancer xenograft tumors was evaluated in subcutaneous and orthotopic xenograft models.

Results

Our results showed that the peptide-sensitized DC-CIK cell preparation manifested significant in vitro cytotoxic activity against the PCSC-enriched prostatospheroids and also in vivo anti-tumor effect against prostate cancer xenografts derived from the PCSC-enriched prostatospheroids.

Conclusions

Together, our established immunogenic peptide-sensitized DC-CIK-based cell preparation platform manifests its potential immunotherapeutic application in targeting the PCSCs and also prostate cancer.

Preoperative ureteral stenting prior to ureteroscopy for management of urolithiasis does not impact the postoperative return for unplanned care

Introduction:

Return for unplanned postoperative care is an important quality metric in the United States. Most of our postoperative return visits occur after ureteroscopy. Routine preoperative ureteral stenting is not recommended by the American Urological Association due to its impact on the quality of life, despite its proposed operative advantages. We evaluated the association between preoperative ureteral stenting and the resulting perioperative outcomes in the context of quality measures such as return to the emergency department (ED) and readmission rates.

Materials and Methods:

After the Institutional Review Board approval, a retrospective review of patients undergoing ureteroscopy from February 2014 to present was conducted. Patient's demographics and perioperative outcomes were compared based on the presence or absence of a ureteral stent before ureteroscopy. Details and rates of nurse calls, returns to the ED, and readmissions within 90 days were also compared.

Results:

A total of 421 instances of ureteroscopy, 278 prestented ureteroscopy (psURS), and 143 direct ureteroscopy (dURS) were included for analysis. Preoperative demographics were similar. The psURS cohort was more likely to undergo flexible ureteroscopy, utilized an access sheath more often (P < 0.0001), and had less ureteral dilation (P < 0.0001). Prestenting did not influence operative time (P = 0.8534) or stone-free rates (P = 0.2241). dURS patients were more likely to call the nurse; however, psURS versus dURS yielded no difference in return to the ED or readmission within 90 days.

Conclusions:

In this study, preoperative stenting offered few operative advantages and did not meaningfully influence returns to the ED and readmissions within 90 days after ureteroscopy.

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

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

Retrograde intrarenal surgery for renal stones - Part 1

The main aim in the treatment of renal stones is to clearance of the stones completely with the least morbidity. Parallel to the improvements in technology during recent years, new flexible ureterorenoscopes and effective lithotripters such as holmium laser have been developed, thus retrograde intrarenal surgery (RIRS) has become an efficient and safe option in the management of urinary system stone disease with a gradually increasing popularity. Therewithal, innovations in auxiliary equipment such as guide-wires, ureteral access sheath and stone baskets have made this procedure more effective. With this modality, nowadays, the vast majority of renal stones can be treated successfully without need of open surgery or percutaneous nephrolithotomy. RIRS can be used as a primary treatment in patients with renal stones smaller than 2 cm, in cases with prior unsuccessful shock wave lithotripsy (SWL), infundibular stenosis, renoureteral malformation, musculoskeletal deformity, bleeding diathesis as well as obese patients. The efficiency of this procedure has been also proved in pediatric patients. In the first part of this detailed review for RIRS, history, indications and contraindications, preoperative preparation, antibiotic prophylaxis, anesthesia, surgical technique related to flexible ureteroscopes and auxiliary equipment being used, postoperative care and complications of this operation are discussed with up-to-date literature.

[S2k guidelines on diagnostics, therapy and metaphylaxis of urolithiasis (AWMF 043/025) : Compendium]

Every tenth German citizen will suffer from at least one urinary calculus during the lifetime. The diagnostics, treatment and follow-up treatment of urolithiasis are, therefore, part of the daily routine practice for all urologists in hospitals and private practices as well as in many other disciplines, such as general practitioners, internists, nephrologists and pediatricians. Although the diagnostics and therapy have experienced substantial alterations over the last 10 years, the possibilities of metabolic diagnostics and secondary prevention for patients at risk are, unfortunately and unjustly, in many places very poorly represented. The present S2k guidelines, which for the first time were established in an interdisciplinary consensus process, represent the current practical recommendations and, whenever possible, use tables and algorithms in order to facilitate easy reference in the routine daily work. Last but not least, this greatly simplifies the measures for metaphylaxis.

[Ureterorenoscopy]

Ureterorenoscopy (URS) is a minimally invasive treatment option for removal of kidney stones, which has gained importance in this field over the past two decades. This technique has replaced extracorporeal shock wave lithotripsy (ESWL) stone surgery for many indications. It is also particularly important in the diagnostics and treatment for tumors of the upper urinary tract. This article describes the indications, surgical technique and management of complications of URS.

The impact of ureteral stent indwelling time on the treatment of acute infection caused by ureteral calculi

Ureteric stenting is an effective drainage method in patients with acute urinary tract infection caused by ureteral calculi; however, the optimal ureteral stent indwelling time has not been clearly defined. The aim of this study was to evaluate the effect of ureteric stent indwelling time on the treatment of acute infection secondary to urinary tract calculi. A total of 142 patients with acute infection caused by urinary tract calculi were identified retrospectively from January 2011 to August 2015 at our institution. 63 patients were with ureteric stenting for 7 days (A group) and 79 patients with ureteric stenting for more than 7 days (B group). The patient characteristics of two groups were analyzed and the clinical data before and after stenting were compared. The postoperative complication outcomes were collected and analyzed. Effective drainage obtained from ureteral stenting clearly abated the infection after stenting for 7 days; WBC count, WBCs in urine, and positive rate of urine culture were significantly decreased compared with the condition of immediate stenting. Both groups showed similar stone clearance rates (96.8% vs. 96.2%, p = 0.841), and there was no significant difference in the rate of postoperative complications, especially related to urinary tract infection (6.3% vs. 6.3%, p = 1.000). It is safe and effective for patients with acute urinary tract infection secondary to urinary tract calculi to be treated by ureteroscopic lithotripsy after stenting for one week. Prolonging the stenting period achieves no added benefit for patients.

Flexible ureteroscopy for renal stone without preoperative ureteral stenting shows good prognosis

Purpose

To clarify the outcome of flexible ureteroscopy (fURS) for management of renal calculi without preoperative stenting.

Methods

A total of 171 patients who received 176 fURS procedures for unilateral renal stones were reviewed. All procedures were divided into two groups depending on whether they received ureteral stenting preoperatively. Baseline characteristics of patients, stone burden, operation time, stone-free rates, and complications were compared between both groups.

Results

Successful primary access to the renal pelvis was achieved in 104 of 114 (91.2%) patients without preoperative stenting, while all procedures with preoperative stenting (n = 62) were successfully performed. A total of 156 procedures were included for further data analysis (56 procedures in stenting group and 100 in non-stenting group). No significant differences was found regardless of a preoperative stent placement in terms of stone-free rate (73.2% with stenting vs. 71.0% without, P = 0.854), operative time (70.4 ± 32.8 with stenting vs. 70.2 ± 32.1 without, P = 0.969).

Conclusions

fURS for management of renal stone without preoperative ureteral stenting are associated with well outcome in short term follow-up. Our study may help patients and doctors to decide if an optional stent is placed or not.

Flexible Ureterorenoscopy for Renal and Proximal Ureteral Stone in Patients with Previous Ureteral Stenting: Impact on Stone-Free Rate and Morbidity

OBJECTIVE

To analyze results (stone-free rate [SFR]) and complications after flexible ureterorenoscopy (f-URS) for renal or lumbar ureteral lithiasis in patients with a previous ureteral stenting (US).

PATIENTS AND METHODS

We conducted a single-center retrospective study, including all f-URS procedures achieved in our department, between January 2004 and December 2010, for renal or lumbar ureteral urinary lithiasis. In total, 497 procedures were performed: 316 procedures in patients with a ureteral stent placed before the surgery for renal colic, sepsis, or renal failure (group 1) and 181 procedures in patients without US (group 2). Success was defined as a complete SFR at 6-month follow-up. Surgical morbidity was defined using the Clavien-Dindo grading system.

RESULTS

Groups 1 and 2 were well balanced in terms of demographic data, number, and size of stones. Ureteral location was significantly higher in group 1 (30.2% vs 16.3%, p = 0.0006). Surgery characteristics were similar in both groups. By univariate analysis, SFR tended to be slightly higher in the group with prior ureteral stenting (72% vs 63%, p = 0.05). SFR for ureteral location was also higher after previous ureteral stenting (81.5% vs 59.4%, p = 0.023). By multivariate analysis, only stone size and number were correlated with f-URS failure. Complication rate was comparable in both groups (10.7% vs 11.8%, p = 0.7).

CONCLUSION

Technical aspects of the f-URS procedure were not modified by ureteral stenting. We found that f-URS in patients with ureteral stenting was not associated with a better SFR, except in case of ureteral location in univariate analysis. Ureteral stenting was not independently related to f-URS outcome by multivariate analysis.

Defining the Rate of Primary Ureteroscopic Failure in Unstented Patients: A Multi-Institutional Study

PURPOSE

Primary ureteroscopic intervention for kidney or ureteral stones occasionally encounters difficulty with passage of the ureteroscope in the initial procedure. These patients require a second procedure after stenting. We aim to define the contemporary failure rate of primary ureteroscopy (URS) and identify predictive factors that necessitate prestenting. This will assist in preoperative patient counseling, informed consent, and clinical decision-making.

MATERIALS AND METHODS

We conducted a multi-institutional retrospective review of 535 unstented patients undergoing primary URS from August 2011 to August 2013. The primary outcome was gaining access to the unstented ureter.

RESULTS

The failure rate for accessing the unstented ureter was 7.7% (41/535). The median age of females with primary ureteroscopic failure was significantly lower than in females who had successful ureteroscopic access (34 vs 52 years; p = 0.0041). There was no difference in the median age of males with access vs failure (58 vs 57 years; p = 0.3683). Proximal ureteral stones had the highest failure rate for ureteral access at 18.28% (p = 0.006). On multivariable logistic regression, proximal ureteral stone location remained a significant predictor of failure when compared to renal stones (odds ratio [OR] 3.14, p = 0.006). When including only ureteral stones in the multivariable analysis, stone location in the proximal ureter compared to the distal ureter remained the only significant predictor of access failure (OR 0.24, p = 0.015).

CONCLUSIONS

A low overall rate of ureteral access failure in unstented patients is shown. Young female patients and proximal ureteral stones were less likely to be accessed primarily. This study provides information that will help urologists counsel their patients preoperatively regarding their likelihood of failing primary URS necessitating a second procedure. This will also help the patient to make an informed decision during the consent process and may guide urologists on selective prestenting in higher risk patients.

[Effect of the body mass index on outcomes of ureterorenoscopy for renal stones]

BACKGROUND

Purpose of this work is to compare the outcome of ureterorenoscopy (URS) with regard to stone-free rates (SFR) and complication rates (CR) in patients with different body mass index (BMI) scores for the treatment of kidney stones.

MATERIALS AND METHODS

A retrospective chart review of all patients with known BMI, who underwent URS for kidney stones between 2006 and 2012 at our institution, was performed (n = 556 patients). The SFR and CR of obese patients were compared to overweight and normal weight patients.

RESULTS

Mean age was 52.51 years and the average BMI 27.74 kg/m². Of the patients, 34.2 % had normal weight (22.59 ± 1.91 kg/m²), 39.6 % were overweight (27.30 ± 1.42 kg/m²), and 26.3 % were obese (35.09 ± 5.93 kg/m²). The mean ASA score differed significantly between normal weight (1.99 ± 0.57), overweight (2.03 ± 0.62), and obese (2.22 ± 0.63) patients (p ≤ 0.036). The mean stone size was 8.51 ± 6.84 mm and the mean number of stones per patient 1.9 ± 2.41, whereby the differences between groups was not significant. There were no differences between the groups regarding the use of preoperative (94.8 %) and postoperative ureteral stents (60.3 %), the Ho:YAG laser (33.6 %), the use of flexible (16.2 %) or semirigid/flexible URS (59.4 %), and the mean operative time (52.04 ± 34.55 min). There were no differences in the SFR for the upper (90 %), mid (94.7 %), and lower pole (90.2 %), multiple location (68.6 %) or the total SFR (86.3 %). Total SFR of 95.7, 88.4, and 73.7 % for urinary calculi < 5 mm, 5-9 mm, and ≥ 10 mm, respectively, were found and the differences between the patient groups was not significant. The CR was 10.4 % (differences between the patient groups not significant).

CONCLUSION

URS is an appropriate treatment for renal stones with high SFR and low CR regardless of patient's BMI.

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

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

CUA Guideline: Management of ureteral calculi

The focus of this guideline is the management of ureteral stones. Specifically, the topics covered include: conservative management, medical expulsive therapy, active intervention with either shockwave lithotripsy (SWL) or ureteroscopy (URS), factors affecting SWL treatment success, optimizing success, and special considerations (e.g., pregnancy, urinary diversion). By performing extensive literature reviews for each topic evaluated, we have generated an evidence-based consensus on the management of ureteral stones. The objective of this guideline is to help standardize the treatment of ureteral stones to optimize treatment outcomes.

Urolithiasis in pregnancy: a cost-effectiveness analysis of ureteroscopic management vs ureteral stenting

OBJECTIVE

The purpose of this study was to determine the cost-effectiveness of serial stenting vs ureteroscopy for treatment of urolithiasis during pregnancy as a function of gestational age (GA) at diagnosis.

STUDY DESIGN

We built decision analytic models for a hypothetical cohort of pregnant women who had received a diagnosis of symptomatic ureteral calculi and compared serial stenting to ureteroscopy. We assumed ureteral stent replacement every 4 weeks during pregnancy, intravenous sedation for stent placement, and spinal anesthetic for ureteroscopy. Outcomes were derived from the literature and included stent infection, migration, spontaneous kidney stone passage, ureteral injury, failed ureteroscopy, postoperative urinary tract infection, sepsis, and anesthetic complications. Four separate analyses were run based on the GA at diagnosis of urolithiasis. Using direct costs and quality-adjusted life years, we reported the incremental costs and effectiveness of each strategy based on GA at kidney stone diagnosis and calculated the net monetary benefit. We performed 1-way and Monte-Carlo sensitivity analyses to assess the strength of the model.

RESULTS

Ureteroscopy was less costly and more effective for urolithiasis, irrespective of GA at diagnosis. The incremental cost of ureteroscopy increased from -$74,469 to -$7631, and the incremental effectiveness decreased from 0.49 to 0.05 quality-adjusted life years for a kidney stone diagnosed at 12 and 36 weeks of gestation, respectively. The net monetary benefit of ureteroscopy progressively decreased for kidney stones that were diagnosed later in pregnancy. The model was robust to all variables.

CONCLUSION

Ureteroscopy is less costly and more effective relative to serial stenting for urolithiasis, regardless of the GA at diagnosis. Ureteroscopy is most beneficial for women who received the diagnosis early during pregnancy.

Current status of flexible ureteroscopy in urology

Retrograde intrarenal surgery (RIRS) is being performed for the surgical management of upper urinary tract pathology. With the development of surgical instruments with improved deflection mechanisms, visuality, and durability, the role of RIRS has expanded to the treatment of urinary calculi located in the upper urinary tract, which compensates for the shortcomings of shock wave lithotripsy and percutaneous nephrolithotomy. RIRS can be considered a conservative treatment of upper urinary tract urothelial cancer (UTUC) or for postoperative surveillance after radical treatment of UTUC under an intensive surveillance program. RIRS has a steep learning curve and various surgical techniques can be used. The choice of instruments during RIRS should be based on increased surgical efficiency, decreased complications, and improved cost-benefit ratio.

Preoperative JJ stent placement in ureteric and renal stone treatment: results from the Clinical Research Office of Endourological Society (CROES) ureteroscopy (URS) Global Study

OBJECTIVE

To compare outcomes of ureteric and renal stone treatment with ureteroscopy (URS) in patients with or without the placement of a preoperative JJ stent.

PATIENTS AND METHODS

The Clinical Research Office of the Endourological Society (CROES) URS Global Study collected prospective data for 1 year on consecutive patients with ureteric or renal stones treated with URS at 114 centres around the world. Patients that had had preoperative JJ stent placement were compared with those that did not. Inverse-probability-weighted regression adjustment (IPWRA) was used to examine the effect of preoperative JJ stent placement on the stone-free rate (SFR), length of hospital stay (LOHS), operative duration, and complications (rate and severity).

RESULTS

Of 8 189 patients with ureteric stones, there were 978 (11.9%) and 7 133 patients with and without a preoperative JJ stent, respectively. Of the 1 622 patients with renal stones, 590 (36.4%) had preoperative stenting and 1 002 did not. For renal stone treatment, preoperative stent placement increased the SFR and operative time, and there was a borderline significant decrease in intraoperative complications. For ureteric stone treatment, preoperative stent placement was associated with longer operative duration and decreased LOHS, but there was no difference in the SFR and complications. One major limitation of the study was that the reason for JJ stent placement was not identified preoperatively.

CONCLUSIONS

The placement of a preoperative JJ stent increases SFRs and decreases complications in patients with renal stones but not in those with ureteric stones.