Outcomes of flexible ureteroscopy and laser fragmentation for treatment of large renal stones with and without the use of ureteral access sheaths: Results from a university hospital with a review of literature

Factors effecting the success of retrograde intrarenal surgery in pediatric patients with renal stones: The experience of two tertiary centres with 368 renal units

INTRODUCTION AND OBJECTIVES

Currently, in the field of pediatric urology, the primary aim of surgical approaches for the treatment of renal stone disease is to provide a stoneless state through minimally invasive methods, and to prevent the damage that such stones may cause in the urinary system and stone recurrence. The aim of this study was to evaluate the efficacy and safety of RIRS and the factors affecting its success in the surgical treatment of renal stones in pediatric patients.

METHODS

Data from 357 pediatric and 368 renal units were collected retrospectively. The recorded parameters were age, gender, location and burden of the stone, and presence of postoperative residual stones.

RESULTS

The stone location was the upper pole in 28 (7.6 %) patients, the middle pole in 44 (12 %), the pelvis in 98 (26.6 %), the lower pole in 139 (37.8 %), and multiple locations in 59 (16 %) patients. A stoneless state was achieved in 277 (75.3 %) units, while 91 units (24.7 %) had residual stones at the end of the first month. In the multivariate analysis, the development of residual stones was found to be significantly associated with age (odds ratio [OR], 1.123; p = 0.012) and stone location (OR, 3.142; p = 0.018).

DISCUSSION

RIRS is an endourological procedure with a high success rate in the achievement of a stoneless state in both pediatric and adult age groups, with an 82-100 % success rate reported in various studies. A full stoneless state was achieved in 277 (75.3 %) units after the initial RIRS in the present study, and full stone clearance was achieved in 304 units after the second RIRS session, with a success rate of 82.6 %. A limitation of our study is that it was not performed by a single surgeon, and stone samples could not be taken from all patients for stone analysis.

CONCLUSION

RIRS has also been associated with a high success rate in the endoscopic treatment of renal stones and is an efficient and safe method with a minimal rate of complications, especially in the pediatric age group.

Impact of ureteric access sheath use during flexible ureteroscopy: A comparative study on efficacy and safety

OBJECTIVES

This study evaluates the impact of using an access sheath (AS) during flexible ureteroscopy (fURS) for urolithiasis treatment, focusing on outcomes such as stone-free rate, operation time, and complications.

METHODS

This prospective, randomized study was carried out at Badr Hospital, Helwan University, and Ain Shams University hospitals from August 2021 to August 2022. Patients were systematically randomized into two groups (fURS with AS: 33 patients and without AS: 31 patients) and underwent preoperative and postoperative assessments, including lab tests and imaging. Possible procedure-associated risks, such as failed stone access, pain, bleeding, and sepsis, were monitored.

RESULTS

The two groups were found to be comparable in terms of demographic characteristics or preoperative stone findings (p > 0.05 for all). However, operation duration was shorter in the No Sheath group (79.4 ± 15.3 min vs. 90.4 ± 16.7 min in the Sheath group, p = 0.008). Intraoperative complication rates, including failed access, operation termination, ureteric injury, and bleeding, were comparable in both groups (p > 0.05). Postoperative stone-free rates (78.8% vs. 71.0%, p = 0.305) and mean residual stone size (2.7 ± 3.5 mm vs. 3.1 ± 3.1 mm, p = 0.687) showed no significant differences.

CONCLUSIONS

The present study suggests that fURS without an access sheath may offer an efficient and equally effective option for managing upper ureteric and renal stones. However, more studies with larger sample sizes and longer follow-up periods are required to validate these findings and to establish more precise indications for this approach.

Different ureteral access sheaths sizes for retrograde intrarenal surgery

PURPOSE

There is a trend toward miniaturization in endourological stone therapy. Good visibility, intrarenal pressures and temperature control should be ensured by ureteral sheaths. In the context of the present study, 10/12 Charr. sheaths and 12/14 Charr. sheaths for flexible ureterorenoscopy were investigated regarding stone-free rate, complication rate and efficacy for laser lithotripsy.

METHODS

From January 2020 to January 2022, 100 patients each with kidney stone up to 1.5 cm in diameter were included in the study. Use of a 12/14 Charr. vs. 10/12 Charr. ureteral sheath for flexible ureterorenoscopy was compared. Perioperative data, stone size, volume and density, laser energy, laser duration, stone-free rates and complications based on Clavien-Dindo classification were retrospectively analyzed.

RESULTS

For both groups of ureteral access sheaths, there were no differences in median surgery duration (10/12 Charr: 29 min (7-105 min) vs. 12/14 Charr: 34 min (9-95 min); p = 0.33), overall complication rate (p = 0.61) and hospitalization (p = 0.155). There were no differences in stone-free rates (97.9% vs. 92.7%, p = 0.37). Laser lithotripsy duration usingholmium laser was 1.9 min (0.1-10.8 min) vs. 3.8 min (0.2-20.7 min) (p < 0.01) and applied laser energy was 3.1 J (0.15 J-10.29 J) vs. 6.8 J (1.07 J-26.77 J) (p < 0.01) for 12/14 Charr. sheaths and 10/12 Charr. sheaths, respectively.

CONCLUSION

In terms of stone-free rates, there are no differences between the 10/12 and 12/14 Charr. ureteral access sheaths. The laser duration and energy was increased with 10/12 Charr. sheaths without showing increased risk for clinical complications like trauma or inflammation.

The Role of 12/14F Ureteral Access Sheath in Flexible Ureteroscopy for Moderate Nephrolithiasis

INTRODUCTION

The aim was a retrospective analysis of 12/14F ureteral access sheath (UAS) usage on perioperative outcomes in patients with moderate nephrolithiasis (MN). MN was defined as a maximum of two unilateral kidney stones with a maximum stone diameter of 6-10 mm.

MATERIAL AND METHODS

We conducted a monocentric retrospective univariate and multivariate analysis of flexible ureteroscopies (fURS) performed for MN between 01/2014 and 12/2018.

RESULTS

A total of 402 fURS were performed in patients with urolithiasis; 112 MN cases underwent further analysis. UAS was successfully applied in 33 MN cases [33/112 (29.46%)]. UAS was inserted regardless of the maximum kidney stone diameter and the presence of multiple kidney stones (p > 0.05). Univariate analysis revealed a prolonged median operation time (UAS: 94 min, non-UAS: 74 min, p = 0.04) and median fluoroscopy time (UAS: 75 s, non-UAS: 57.5 s, p = 0.04) in the UAS cohort. These differences were not confirmed on multivariate logistic regression.UAS was not associated with better stone-free rates in either the univariate or multivariate analysis (UAS: 26/33, non-UAS: 61/79, p = 1.0) nor with the occurrence of Clavien-Dindo ≥2 complications (UAS: 3/33, non-UAS: 9/79, p = 0.98) or median length of hospital stay (UAS: 2 days, non-UAS: 2 days, p = 0.169).

CONCLUSION

We identified no statistical benefits from the usage of 12/14F UAS for MN. As no relevant UAS-associated complications were documented, both strategies (with and without UAS) are feasible.

Influencing factors of acute kidney injury following retrograde intrarenal surgery

PURPOSE

To investigate the influencing factors of acute kidney injury (AKI) following retrograde intrarenal surgery (RIRS).

METHODS

The data of patients who underwent RIRS for kidney stones between January 2018 and June 2022 at two tertiary centers were retrospectively analyzed. Demographic data of patients were obtained. According to kidney disease: Improving Global Outcomes (KDIGO) criteria, those with and without AKI were divided into two groups. Preoperative, intraoperative, and postoperative predictive factors of patients were investigated between the groups. In addition, the influencing factors of AKI were examined by multivariate analysis.

RESULTS

This study included 295 (35.7%) women and 532 (64.3%) men. The mean age was 50.03 ± 15.4 years (range 18-89), and mean stone size was 15.5 ± 6.1 mm (range 6-47). Overall, 672 of patients (81.3%) were stone-free after the initial treatment. According to KDIGO, 110 of patients (13.3%) had AKI during the postoperative period. Univariate analysis showed that stone size (P = .003), previous stone surgery (P = .010), renal malformations (P = .017), high operative time (P =  < .001), high preoperative creatinine value (P = .036), intraoperative complications (P = .018), and postoperative urinary tract infection (P = .003) had significant influence on the AKI after RIRS. Multivariate analysis excluded previous stone surgery, high preoperative creatinine value, renal malformations, and intraoperative complications from the logistic regression model, whereas other factors maintained their statistically significant effect on AKI, indicating that they were independent predictors.

CONCLUSIONS

Stone size, operative time, postoperative urinary tract infection, and diabetes mellitus are significant predictors of AKI. During RIRS, urologists should consider the factors that increase the risk of AKI and evaluate the treatment outcomes based on these factors.

Role of Pediatric Ureteral Access Sheath and Outcomes Related to Flexible Ureteroscopy and Laser Stone Fragmentation: A Systematic Review of Literature

Context

Flexible ureteroscopy and laser lithotripsy (FURSL) represent a good treatment option for pediatric urolithiasis. Scarce evidence is available about the safety and efficacy of the concomitant use of a ureteral access sheath (UAS) in the setting of pediatric ureteroscopy (URS).

Objective

To acquire all the available evidence on UAS usage in pediatric FURSL, focusing on intra- and postoperative complications and stone-free rates (SFRs).

Evidence acquisition

We performed a systematic literature research using PubMed/MEDLINE, Embase, and Scopus databases. The inclusion criteria were cohorts of pediatric patients <18 yr old, submitted to URS for FURSL, reporting on more than ten cases of UAS placement. The primary outcomes were prestenting rates, operating time, ureteric stent placement rates after surgery, rates and grades of complications, ureteral injuries, and overall SFR. A total of 22 articles were selected.

Evidence synthesis

In total, 26 intraoperative and 130 postoperative complications following URS with UAS placement were reported (1.8% and 9.18% of the overall procedures, respectively). According to the Clavien-Dindo classification, 32 were classified as Clavien I, 29 as Clavien II, 43 as Clavien I or II, six as Clavien III, and one as Clavien IV. Twenty-one cases of ureteral injuries (1.59%) were noted in the whole cohort; most of them were ureteral perforation or extravasation, and were treated with a temporary indwelling ureteric stent. The overall SFR after a single URS procedure was 76.92%; after at least a second procedure, it was 84.9%.

Conclusions

FURSL is a safe and effective treatment option for pediatric urolithiasis. UAS use was associated with a low rate of ureteric injuries, mostly treated and resolved with a temporary indwelling ureteric stent.

Patient summary

We performed a systematic literature research on the utilization of a UAS during ureteroscopy for stone treatment in pediatric patients. We assessed the outcomes related to the rates of intra- and postoperative complications and the rates of efficacy of the procedure in the clearance of stones. The evidence shows a low rate and grade of complications associated with UAS placement and good stone-free outcomes. A ureteric injury may occur in 1.6% of cases, but it is usually managed and resolved with a temporary indwelling ureteric stent.

Comparison of retrograde intrarenal stone surgery with and without a ureteral access sheath using kidney injury molecule-1 (KIM-1) levels: a prospective randomized study

The objective is to compare patients who underwent retrograde intrarenal surgery with and without a ureteral access sheath (UAS) using kidney injury molecule-1 (KIM-1) levels. We also examined the difference in kidney damage between standard and dual lumen UAS. Sixty patients diagnosed with kidney stones and scheduled for RIRS were randomized into three groups: RIRS without UAS (Group 1), 11Fr/13Fr Boston scientific Navigator™ UAS (Group 2), and 11Fr/13Fr dual lumen ClearPetra™ UAS (Group 3). Data were prospectively collected in consecutive patients. Urine KIM-1/Cr levels were measured preoperatively, at postoperative 4 h, and on a postoperative day 14. Stone size, location, number, pre- and postoperative stent use, operation time, stone-free rate (SFR), post-ureteroscopic lesion scale (PULS) grade, hospitalization duration, and complications were recorded. There was no significant difference in demographical parameters and preoperative KIM-1/Cr levels among the groups. Postoperative 4th-hour urine KIM-1/Cr levels were higher in patients without UAS than patients with UAS (1.86, 0.67, 0.63 Groups 1, 2, 3, respectively). In comparing group 1 with groups 2 and 3 separately, Group 1 had a statistically significantly higher value than both groups (p = 0.002, p = 0.001, respectively). According to UAS type, there was no significant difference between groups 2 and 3. The use of UAS during RIRS has been shown to reduce kidney injury in the evaluation with KIM-1. Different UAS types on kidney injury and which one can protect the kidneys more during the procedure; will be elucidated by prospective randomized studies involving larger patient groups and UAS types.

Comparison of retrograde intrarenal stone surgery with and without a ureteral access sheath using kidney injury molecule-1 (KIM-1) levels: a prospective randomized study

The objective is to compare patients who underwent retrograde intrarenal surgery with and without a ureteral access sheath (UAS) using kidney injury molecule-1 (KIM-1) levels. We also examined the difference in kidney damage between standard and dual lumen UAS. Sixty patients diagnosed with kidney stones and scheduled for RIRS were randomized into three groups: RIRS without UAS (Group 1), 11Fr/13Fr Boston scientific Navigator™ UAS (Group 2), and 11Fr/13Fr dual lumen ClearPetra™ UAS (Group 3). Data were prospectively collected in consecutive patients. Urine KIM-1/Cr levels were measured preoperatively, at postoperative 4 h, and on a postoperative day 14. Stone size, location, number, pre- and postoperative stent use, operation time, stone-free rate (SFR), post-ureteroscopic lesion scale (PULS) grade, hospitalization duration, and complications were recorded. There was no significant difference in demographical parameters and preoperative KIM-1/Cr levels among the groups. Postoperative 4th-hour urine KIM-1/Cr levels were higher in patients without UAS than patients with UAS (1.86, 0.67, 0.63 Groups 1, 2, 3, respectively). In comparing group 1 with groups 2 and 3 separately, Group 1 had a statistically significantly higher value than both groups (p = 0.002, p = 0.001, respectively). According to UAS type, there was no significant difference between groups 2 and 3. The use of UAS during RIRS has been shown to reduce kidney injury in the evaluation with KIM-1. Different UAS types on kidney injury and which one can protect the kidneys more during the procedure; will be elucidated by prospective randomized studies involving larger patient groups and UAS types.

The dilemma of 12/14F ureteral access sheath (UAS) usage: a case control study

BACKGROUND

The insertion of a ureteral access sheath (UAS) is a frequent procedure during flexible ureteroscopy (fURS) to facilitate kidney stone treatment. The aim of this study was to investigate the influence of 12/14 French (F) UAS on fURS outcomes.

METHODS

We performed a retrospective monocentric analysis of fURS procedures conducted at the Department of Urology (University Hospital Schleswig-Holstein, Lübeck, Germany) for kidney stone treatment via lithotripsy or basket stone retrieval between September 2013 and June 2017. Uni- and multivariate analyses were done with the help of RStudio (Version 1.0.136) software.

RESULTS

In total, 283 consecutive fURS were analyzed. UAS was applied in 98 cases (34.63%). The insertion of UAS was preferred in cases with multiple kidney stones and larger median maximal stone diameter (p < 0.05). UAS usage correlated with elevated radiation exposure in seconds (94 vs. 61; p < 0.0001), prolonged operation time in minutes (99 vs. 66, p < 0.0001), length of hospital stay over 48 h (LOS, 22.49% vs. 10.81%; p = 0.015), more frequent postoperative systemic inflammatory response syndrome (SIRS, 13.27% vs. 4.32%; p = 0.013) and lower postoperative stone-free rates (60.20% vs. 78.92%; p = 0.0013). Moreover, we conducted uni- and multivariate subgroup analysis for cases with multiple kidney stones (≥ 2) and comparable stone burden; UAS was inserted in 48.3% of these cases (71/147). On multivariate logistic regression, UAS insertion was statistically associated with prolonged operation time in minutes (101 vs. 77; p = 0.004). No statistical differences regarding radiation exposure, stone-free rates, postoperative SIRS rates or LOS were noted between UAS and non-UAS patients with multiple kidney stones of similar size (p > 0.05).

CONCLUSIONS

12/14F UAS does not seem to improve overall outcomes in fURS for kidney stones. In patients with multiple kidney stones it may be associated with elevated operation time without a clear benefit in terms of improved stone-free status or reduced perioperative complication rate. Further prospective randomized studies to specify the indications for UAS usage are urgently needed.

Comparison of flexible ureteroscopy and mini-percutaneous nephrolithotomy in the treatment for renal calculi larger than 2 cm: a matched-pair analysis

To compare the effectiveness and safety of flexible ureteroscopy and mini-percutaneous nephrolithotomy for renal calculi > 2 cm and perform subgroup analysis of stone length and age. Patients received mini-percutaneous nephrolithotomy or flexible ureteroscopy in Qilu Hospital of Shandong University from 2016.01 to 2021.03 with renal calculi > 2 cm were retrospectively analyzed. Propensity score matching was performed to get comparable patients. The postoperative hospital days, operation time, complication rate, and stone free rate were compared. The age and stone length were analyzed by subgroup. 162 in 313 patients were finally included. Each group had 81 cases. Outcomes such as intraoperative transfusion, stone free rate show no difference either. Flexible ureteroscopy had shorter postoperative hospital days (3.2 days vs 7.2 days, P < 0.001) and fewer complications (9, 11.1% vs 25, 30.9%, P = 0.002) compared to mini-percutaneous nephrolithotomy. The postoperative hospital days, and complication of the flexible ureteroscopy were significantly lower than those in the mini-percutaneous nephrolithotomy for renal stones ≤ 2.5 cm; when the stone length > 2.5 cm, the stone free rate of flexible ureteroscopy was lower than that of the mini-percutaneous nephrolithotomy group, but not statistically significant. The complications of flexible ureteroscopy in the young group (18-39 years old) were significantly lower than those in the mini-percutaneous nephrolithotomy group. For 2-2.5 cm renal stones, flexible ureteroscopy can achieve a similar stone free rate with shorter hospital stay, and lower complications. For larger stones, flexible ureteroscopy performed poorly. Flexible ureteroscopy may be a better option for younger patients with fewer complications.

Can We Identify Patients in Danger of Complications in Retrograde Intrarenal Surgery?-A Retrospective Risk Factors Analysis

Retrograde intrarenal surgery (RIRS) is an innovative and effective method of kidney stones treatment, as it had great influence on the development of endoscopy in urology. The increasing prevalence of urolithiasis together with the rapid development of endourology leads to a rise in the number of procedures related to the disease. Flexible ureteroscopy is constantly being improved, especially regarding the effectiveness and safety of the procedure. The purpose of this study is to evaluate intraoperative and early post-operative complications of RIRS in the treatment of kidney stones. A retrospective analysis of medical records was performed. A series was comprised of 207 consecutive operations performed from 2017 to 2020. Complications occurred in 19.3% (n = 40) of patients. Occurrence according to the Clavien-Dindo scale was: 11.1% for grade I, 5.8% for grade II and 2.4% for grade IV. Infectious complications included SIRS (5.3%, n = 11) and sepsis (2.4%, n = 5). Statistical analysis revealed a correlation between acute post-operative infections and positive midstream urine culture, history of chronic or recurrent urinary tract infections, and increased body mass index (BMI). Furthermore, a significant correlation was observed between pain requiring the use of opioids with BMI over 25. Consequently, history of urinary tract infections, positive pre-operative urine culture, and increased BMI are considered risk factors and require appropriate management.

Does ureteral access sheath have an impact on ureteral injury?

Objective:

To present a well-organized review about ureteral access sheath impact on ureteral injury.

Materials and Methods:

Systemic search on literature was done. Total of 3766 studies observed by two urologists and results were unified. A Prisma diagram was used for eliminating irrelevant studies and at the end of elimination process 28 studies were found eligible for this review.

Results:

Not only clinical studies but also comparative experimental animal studies show that there is no significant data to claim that ureteral access sheath insertion causes more ureteral injury. Pre-stented patients were found to be at lower risk for ureteral injury. Risk of progression to ureteral injury seems to be low even if ureteral injury occurs with insertion of ureteral access sheath.

Conclusion:

Summary of studies’ results indicate that use of ureteral access sheath doesn’t increase ureteral injury. This review may help understanding safety profile of ureteral access sheath on evidence-based level. There is not enough data to make a statement that ureteral access sheath prevents ureteral injury.

Design and Performance Investigation of a Robot-Assisted Flexible Ureteroscopy System

Flexible ureteroscopy (FURS) has been developed and has become a preferred routine procedure for both diagnosis and treatment of kidney stones and other renal diseases inside the urinary tract. The traditional manual FURS procedure is highly skill-demanding and easily brings about physical fatigue and burnout for surgeons. The improper operational ergonomics and fragile instruments also hinder its further development and patient safety enhancement. A robotic system is presented in this paper to assist the FURS procedure. The system with a master-slave configuration is designed based on the requirement analysis in manual operation. A joint-to-joint mapping strategy and several control strategies are built to realize intuitive and safe operations. Both phantom and animal experiments validate that the robot has significant advantages over manual operations, including the easy-to-use manner, reduced intraoperative time, and improved surgical ergonomics. The proposed robotic system can solve the major drawbacks of manual FURS. The test results demonstrate that the robot has great potential for clinical applications.

Retrograde intrarenal surgery versus percutaneous nephrolithotomy for treatment of renal pelvic stone more than 2 centimeters: a prospective randomized controlled trial

This study aimed at investigating the efficacy and safety of retrograde intrarenal surgery (RIRS) in treatment of renal pelvic stone larger than 2 cm against the percutaneous nephrolithotomy (PCNL). Between March 2018 and December 2020, 121 patients were randomized to undergo PCNL (60 patients), or RIRS (61 patients). Both groups were compared in terms of operative time, intraoperative complications. Postoperative complications were assessed based on Clavien-Dindo grading system. Stone-free rates were evaluated by CT scan 6 weeks after surgery. No significant difference were observed between both groups in perioperative criteria. The main operative time was slightly longer in PCNL group (105 vs 95 min, p = 0.49). Stone clearance was higher in PCNL, yet the difference was not significant. (53 patients in PCNL group had either complete clearance or residual fragments < 4 mm, compared to 49 in RIRS group (p = 0.22). Blood transfusion rate was 8.3% in PCNL compared to 1.6% in RIRS group, with a trend towards significance (p = 0.08). Post-operative fever was higher in RIRS, yet it fell just short of statistical significance (13.1% vs 5.0%, p = 0.12). Compared to PCNL, RIRS displayed acceptable efficacy with less risk of bleeding requiring transfusion. It can be applied to patients with large renal pelvic stone as an alternative to PCNL.

Impact of ureteral access sheath on renal stone treatment: prospective comparative non-randomised outcomes over a 7-year period

PURPOSE

To compare the outcomes (stone free rate and complications) of renal stone treatment with and without the use of ureteral access sheath (UAS). The worldwide use of UAS has risen over the last decade; however, questions still remain on the safety and outcomes with its use. We wanted to look at the role of UAS for treatment of consecutive renal stones over a 7-year period.

METHODS

The outcomes of flexible ureteroscopy and stone treatment (FURS) for renal stones with and without the use of UAS was prospectively compared from March 2012 to July 2018. Patients were divided into two groups: group-1 where UAS was used for stone treatment and group-2 where a UAS was not used. Data were collected prospectively on consecutive patients for demographics, stone size, location and number, pre and post-operative stent usage, operative time duration, stone free rate (SFR), length of stay and complications.

RESULTS

During the study period, 338 patients underwent FURS for renal stones, of which a UAS was used for 203 (60%) patients. The mean age of patients was 56 years (range 2-89 years) with a male:female ratio of 204:134. The mean cumulative stone size and the mean number of stones was 16.5 ± 10.8 mm and 11.37 ± 8.08 mm (P < 0.001), and 2.17 ± 1.99 and 1.66 ± 1.50 (P = 0.009) for groups 1 and 2 respectively. The pre and post-operative stent insertion rates were similar in the two groups. The procedural time was longer in group-1 (54.8 ± 25.8 min) compared to group-2 (41.3 ± 22.2 min) (P < 0.001). The SFR for group-1 (88%) was slightly lower than group-2 (94%) although this was not statistically significant (P = 0.07). There were no intra-operative complications in either of the groups. Post-operative complications were seen in eight patients in group-1 (7 Clavien I/II and 1 Clavien IVa) and two patients in group-2 (Clavien I) (P = 0.19).

CONCLUSION

The use of UAS for renal stones is safe with no intra-operative complications noted in our series. Good stone-free rates were obtained for large and multiple renal stones with a small risk of minor complications post-operatively.

Predictors of Urinary Infections and Urosepsis After Ureteroscopy for Stone Disease: a Systematic Review from EAU Section of Urolithiasis (EULIS)

PURPOSE OF REVIEW

To present the latest evidence related to the predictors of urinary tract infections (UTIs) and urosepsis after ureteroscopy (URS) for stone disease.

RECENT FINDINGS

Our review suggests that almost half of all post-URS complications are related to infectious complications although reported rates of urosepsis were low. The use of antibiotic prophylaxis, treatment of pre-operative UTI, and low procedural time seem to reduce this risk. However, the risk is higher in patients with higher Charlson comorbidity index, elderly patients, female gender, long duration of pre-procedural indwelling ureteric stents and patients with a neurogenic bladder and with high BMI. Infectious complications following ureteroscopy can be a source of morbidity and potential mortality. Although majority of these are minor, efforts must be taken to minimise them especially in high-risk patients. This includes the use of prophylactic antibiotics, limiting stent dwell and procedural time, prompt identification and treatment of UTI and urosepsis, and careful planning in patients with large stone burden and multiple comorbidities.

Pictorial review of tips and tricks for ureteroscopy and stone treatment: an essential guide for urologists from PETRA research consortium

With an increase in the number of ureteroscopy (URS) procedures, URS is now performed more widely and is becoming a standard procedure for all urologists. There is also a rise in the complexity of these procedures and URS is now offered for treatment of stones as well as for diagnosis and treatment of urothelial tumours. We wanted to provide a 'pictorial review' of the 'tips and tricks' of URS, as the finer and technical details are often easier to understand and remember with images rather than through textual explanations.

Sheathless and fluoroscopy-free retrograde intrarenal surgery: An attractive way of renal stone management in high-volume stone centers

Objective

To evaluate the efficacy and safety of sheathless and fluoroscopy-free flexible ureterorenoscopic laser lithotripsy (FURSL) for treating renal stones.

Methods

Between May 2015 and May 2017, 135 patients with renal stones treated with sheathless and fluoroscopy-free FURSL were prospectively evaluated. Our technique involved a semi-rigid ureteroscopic assessment of the ureter, and the guidewire was left in situ to railroad the flexible ureteroscope. A holmium laser was used to fragment and dust the stones; fragments were neither grasped nor collected.

Results

The study population consisted of 135 patients including 85 males (62.96%) and 50 females (37.04%) with a mean age of 40.65 years (range: 3–70 years) were evaluated. The mean stone size was 17.23 mm (range: 8–41 mm). Complete stone-free status was achieved in 122 (90.37%) patients and clinically insignificant residual fragments (CIRF) in two (1.48%), while residual stones were still present in 11 (8.15%) patients. Postoperative complications occurred in 23 (17.4%) cases and were mostly minor, including fever in 17 (12.6%), pyelonephritis in four (3.0%), subcapsular hematoma in one (0.7%) and steinstrasse in one (0.7%). These complications were Clavien I-II, GI in 17 (12.6%) patients, GII in five (3.7%), and Clavien IIIb in one (0.7%). No major complications were observed. Stone size ≥2 cm, operative time ≥30 min, and lasing time ≥20 min were significantly associated with a higher rate of complications and lower stone-free rates upon univariate analysis (p<0.05).

Conclusion

Sheathless and fluoroscopy-free FURSL are effective and safe for renal stone management, especially for stones under 2 cm in diameter. This process is a feasible option for avoiding sheath complications, which can protect surgeons from the negative effects of radiation.

The effect of using ureteral access sheath for treatment of impacted ureteral stones at mid-upper part with flexible ureterorenoscopy: a randomized prospective study

BACKGROUND

The number of the studies made on the efficacy of flexible ureteroscopy (FURS) with ureteral access sheath (UAS) for impacted ureteral stones is limited. The aim of our study was to compare the efficacy and reliability of FURS in treatment of mid-upper impacted ureteral stones in cases where access is used or not.

METHODS

Between January 2017 and June 2018, 131 adult patients who applied to our clinic with complaints of mid-upper impacted ureteral stones. Patients were randomized as group 1 (without UAS) and group 2 (with UAS) by means of a draw and assessed in terms of demographic features, stone size, stone localization, hydronephrosis grade, operation time, scope time, the need for additional surgery, hospitalization time and complications.

RESULTS

The mean age of the patients in group 1 was 45.01 years (19-76) and was 37.01 years (16-80) in group 2. Mean stone size was 9.04 mm2 and 9.77 mm2 in group 1 and 2, respectively. Additional treatment was required for 26 (42.6%) patients in group 1 and 8 (11.4%) in group 2. No major intraoperative and postoperative complications developed in both groups. Although bleeding as a postoperative complication rate was similar, fever (>38° C) and urinary tract infection were higher in group 1 than in group 2.

CONCLUSIONS

In the treatment of mid-upper impacted ureteral stones, using UAS during the application of FURS is an advantageous procedure due to shorter operation time, fever intraoperative stone migrations and the need for additional surgery, less postoperative infection.

Outcomes and Long-Term Follow-Up with the Use of Ureteral Access Sheath for Pediatric Ureteroscopy and Stone Treatment: Results from a Tertiary Endourology Center

PURPOSE

The aim of this study was to retrospectively analyze outcomes of flexible ureteroscopy and laser fragmentation (FURSL) of renal stones with the use of ureteral access sheath (UAS) in the pediatric population.

MATERIALS AND METHODS

We retrospectively collected data between January 2011 and January 2018 for patient demographics, stone characteristics, and outcomes in 21 children who underwent FURSL with the use of UAS.

RESULTS

Twenty-one patients (10 boys and 11 girls) with a mean age of 11.8 years (range: 2-16 years) underwent FURSL using an access sheath. The stone location was in the lower pole in 13 patients (62%) with 12 patients (57%) having multiple stones. A 9.5F (35 cm) Cook Flexor UAS was used in all cases. The mean and overall stone size was 12 mm (range: 5-30 mm) and 15.4 mm (range: 5-35 mm), respectively. Preoperative stent was present in 8(38%) patients, and a postoperative stent or overnight ureteric catheter was inserted in 14 patients (67%). Thirty-one procedures (average: 1.5/patient) were needed to achieve a stone-free rate of 95%. There were no procedural or long-term complications noted over a mean follow-up of 26 months (4-37 months).

CONCLUSION

The use of UAS in the treatment of pediatric renal stones is safe and feasible with good outcomes and without any long-term sequelae.

Updates in endourological management of urolithiasis

Urinary stone disease, or urolithiasis, is a very common disease with increasing prevalence and incidence. With the advancement of endoscopic techniques, the treatment outcomes of ureteroscopy (or transureteral lithotripsy) and percutaneous nephrolithotomy are continuously improving. In recent years, there have been many new developments in the field, including new endoscopy design, more effective auxiliary tools, improvement in treatment protocols, introduction of robotic technology, combining both ureteroscopy and percutaneous nephrolithotomy (endoscopic combined intrarenal surgery or transureteral lithotripsy-assisted percutaneous nephrolithotomy), improvement in laser technology, and so on. All these new inputs will further improve the treatment efficacy and safety of the procedures, thus benefiting our patients. In the present review, we briefly go through the main steps of ureteroscopy and percutaneous nephrolithotomy, with a concise description and application of these new advances.

Comparison of utilization of pressurized automated versus manual hand irrigation during ureteroscopy in the absence of ureteral access sheath

This study compared patient outcomes following irrigation applied using an automated pressure system (AP) to hand irrigation utilizing a syringe (HI) during ureteroscopy. Retrospective chart review was performed to evaluate ureteroscopy procedures without a ureteral access sheath. Procedures in which irrigation was applied by AP were compared to those with HI. Statistical analyses included chi-squared tests and Student's t tests. The AP group contained 206 procedures and the HI group, 25. The AP and HI groups were 54.9% and 36% male, respectively. Mean ages were 53.7 ± 18.9 years in the AP group and 44.0 ± 18.5 years in the HI group. Complication rates were 11.2% in the AP and 8.3% in the HI group (P > 0.99). One stone retrieval failure and one stone recurrence occurred in the HI group; one patient had residual stone in the AP group. No urinary tract infections occurred in the HI group; in the AP group, urinary tract infections occurred in 1.9% of cases. The postoperative pain incidence was equivalent (P = 0.498). The AP group had one subcapsular hematoma; no calyceal ruptures occurred in either group. In conclusion, irrigation applied by an automated setup appears safe, with similar outcomes to irrigation applied with a handheld syringe.

Role of 'dusting and pop-dusting' using a high-powered (100 W) laser machine in the treatment of large stones (≥ 15 mm): prospective outcomes over 16 months

Ureteroscopy and laser stone fragmentation (URSL) has had recent advancements with the more powerful laser systems with the ability to ‘dust’ and ‘pop-dust’ the stone. We wanted to look at the outcomes of this method for large stones (≥ 15 mm) using our new 100 W holmium laser. Over a period of 16 months (January 2017–April 2018), 50 patients underwent URSL for minimum cumulative stone size of ≥ 15 mm. Data were collected prospectively on patient and stone demographics and outcomes of URSL. The laser setting used was a power of 0.3–0.6 J and a frequency of 20–50 Hz using a long-pulse setting with a 272-µm fiber. Fifty patients underwent 55 URSL procedures (5 bilateral procedures) using dusting and pop-dusting settings. The mean age was 58 years (range 2–88 years) with a male:female ratio of 35:15. The mean single and overall stone size were 10.3 mm (3–23 mm) and 21 mm (range 15–52 mm) with two-thirds of all patients (65%) having multiple stones. The stone location was in the kidney (n = 65, 78%), in the ureter (n = 19, 22%) and 5 patients had bilateral renal stones. With a mean operating time of 51 min, the initial and final SFR were 93 and 98%, respectively. A pre-operative stent, access sheath and a post-operative stent were present in 29 (53%), 34 (62%) and 51 (93%) procedures, respectively. Over a mean hospital stay of 0.6 days (74% day-case procedures), there was one Clavien IV complication related to urosepsis but without any other major or minor complications. Dusting and pop-dusting techniques achieve an excellent SFR with low risk of complications even for large stones. This might set a new benchmark for treating large stones, bilateral or multiple stones in a single setting, without the need for secondary procedures in most cases.

Systematic review of ureteral access sheaths: facts and myths

The aim of the present paper was to review the literature on all available ureteral access sheaths (UASs) with their indications, limitations, risks, advantages and disadvantages in current modern endourological practice. Two authors searched Medline, Scopus, Embase and Web of Science databases to identify studies on UASs published in English. No time period restriction was applied. All original articles reporting outcomes or innovations were included. Additional articles identified through references lists were also included. Case reports, editorials, letters, review articles and meeting abstracts were excluded. A total of 754 abstracts were screened, 176 original articles were assessed for eligibility and 83 articles were included in the review. Based on a low level of evidence, UASs increase irrigation flow during flexible ureteroscopy and decrease intrapelvic pressure and probably infectious complications. Data were controversial and sparse on the impact of UASs on multiple reinsertions and withdrawals of a ureteroscope, stone-free rates, ureteroscope protection or damage, postoperative pain, risk of ureteral strictures, and also on its cost-effectiveness. Studies on the benefit of UASs in paediatrics and in patients with a coagulopathy were inconclusive. In the absence of good randomized data, the true impact of UASs on surgery outcome remains unclear. The present review may contribute to the evidence-based decision-making process at the individual patient level regarding whether or not a UAS should be used.

Use of the ureteral access sheath during ureteroscopy: A systematic review and meta-analysis

The debate still rages on for the usefulness of ureteral access sheath (UAS). Therefore, a meta-analysis to discuss the effects of applying UAS during ureteroscopy was performed. The protocol for the review is available on PROSPERO (CRD42017052327). A literature search was conducted up to November, 2017 using the Web of science, PUBMED, EMBASE and Cochrane Library. The quality of articles was assessed by the Jadad scale and Newcastle Ottawa Scale (NOS). Egger’s test and the trim-and-fill method were used to evaluate publication bias. Effect sizes were calculated by pooled odds ratio (ORs) and mean differences (MDs). Sensitivity analyses and subgroup analyses were performed to explore the origin of heterogeneity. Eight trials with a total of 3099 patients and 3127 procedures were identified. Results showed no significant difference in stone-free rate (SFR) (OR = 0.83, 95% CI 0.52–1.33, P = 0.45), intraoperative complications (OR = 1.16, 95% CI 0.81–7.69, P = 0.88), operative time (MD = 4.09, 95% CI -15.08–23.26, P = 0.68) and hospitalization duration (MD = -0.13, 95% CI -0.32–0.06, P = 0.18). However, the incidence of postoperative complications was higher in UAS group (OR = 1.46, 95% CI 1.06–2.00, P = 0.02). Evidence from meta-analysis indicated that the use of UAS during ureteroscopy did not manifest advantages. However, given the intrinsic restrictions of the quality of selected articles, more randomized controlled trials (RCTs) are warranted to update the findings of this analysis.

In Vitro Comparison of Maximum Pressure Developed by Irrigation Systems in a Kidney Model

Purpose: To evaluate in vitro the maximum pressure generated in an artificial kidney model when people of different levels of strengths used various irrigation systems. Materials and Methods: Fifteen people were enrolled and divided into three groups based on their strengths. Individual strength was evaluated according to the maximum pressure each participant was able to achieve using an Encore™ Inflator. The irrigation systems evaluated were as follows: T-Flow™ Dual Port, Hiline™, continuous flow single action pumping system (SAPS™) with the system close and open, Irri-flo II™, a simple 60-mL syringe, and Peditrol™. Each irrigation system was connected to URF-V2 ureteroscope, which was inserted into an artificial kidney model. Each participant was asked to produce the maximum pressure possible with every irrigation device. Pressure was measured with the working channel (WC) empty, with a laser fiber, and a basket inside. Results: The highest pressure was achieved with the 60 mL-syringe system and the lowest with SAPS continuous version system (with continuous irrigation open), compared to the other irrigation devices (p < 0.0001). Irrespective of the irrigation system, there was a significant difference in the pressure between the WC empty and when occupied with the laser fiber or the basket inside it (p < 0.0001). The stratification between the groups showed that the most powerful group could produce the highest pressure in the kidney model with all the irrigation devices in almost any situation. The exception to this was the T-Flow system, which was the only device where no statistical differences were detected among these groups. Conclusion: The use of irrigation systems can often generate excessive pressure in an artificial kidney model, especially with an unoccupied WC of the ureteroscope. Depending on the strength of force applied, very high pressure can be generated by most irrigation devices irrespective of whether the scope is occupied or not.

Ureteroscopy and laser stone fragmentation (URSL) for large (≥1 cm) paediatric stones: Outcomes from a university teaching hospital

INTRODUCTION

The treatment of large renal stones (≥1 cm) in paediatric patients is challenging. The usual treatment options include percutaneous nephrolithotomy (PCNL) or shockwave lithotripsy (SWL). There is a rise in the use of ureteroscopy and laser stone fragmentation (URSL) for paediatric stones; however, outcomes of treatment for large renal stones in this age group are still largely unknown.

OBJECTIVE

To investigate the outcome of URSL for large paediatric renal stones ≥1 cm treated at the present institution over the last 5 years.

METHODS

A retrospective review was performed of outcomes from the prospectively maintained stone database. Only paediatric patients undergoing ureteroscopic (rigid or flexible ureteroscopy (URS)) procedures for stones ≥1 cm were included. Patient demographics, operative details, stone burden, hospital stay, complications and stone clearance were recorded and analysed.

RESULTS

From April 2010 to June 2015, 18 paediatric patients with a mean age of 10.4 years (range 3.6-15) underwent 35 ureteroscopic procedures for large stones (≥1 cm). The stone location was in the kidney (n = 14), ureter (n = 1), and in both the kidney and ureter for the remaining three patients. Nine patients had multiple stones. There was a preceding history of PCNL in four patients, with one patient having URS combined with a PCNL. The mean follow-up was 2.7 years (range 0-5). A postoperative stent was inserted in 21 (60%) patients. The overall stone-free rate (SFR) was 89% for a mean of 1.8 procedures per patient (range 1-4) - see Summary Table below. There was an inability to access stone within a lower pole calyx in one patient, despite maximum deflection of the ureteroscope. No intra- or post-operative complications were noted, and mean hospital stay was 1.1 days (range 0-5).

DISCUSSION

Published papers in adult literature have shown that ureteroscopy and laser fragmentation (URSL) is a viable alternative to PCNL. Newer equipment and improved techniques have resulted in SFRs being comparable with PCNL. A recent systematic review reported an SFR of 91% for large adult stones (>2 cm) for a mean 1.45 procedures per patient, and an overall complication rate of 8.6%. The present study has also demonstrated excellent outcomes in the use of ureteroscopy and laser fragmentation for the management of large paediatric stones with no complications.

CONCLUSION

The results show that paediatric URSL for large stones achieves a good SFR with minimal morbidity and is a good treatment option in established endourological units.

Is a ureteral stent required after use of ureteral access sheath in presented patients who undergo flexible ureteroscopy?

Introduction

Use of a ureteral access sheath (UAS) within flexible ureteroscopy (fURS) for the management of kidney and ureteral stones has shown improvements in its effectiveness, but it is also associated with increased risk of ureteral injury. Use of ureteral stent (US) after fURS is recommended by some authors, because of its role in reducing postoperative pain and preventing complications. Our objective is to determine if postoperative stenting is necessary in pre-stented patients that underwent fURS using UAS.

Material and methods

A retrospective history review of patients who underwent fURS using UAS at our hospital between July 1^st 2013 and May 31^st 2016 was performed. Only pre-stented patients were included. All procedures were performed using the same UAS (Boston Navigator TM., 11–13 Fr.). Patients were separated according to the use or not of postoperative US. The same US (26 cm 6 Fr percuflex, Boston Scienfic) was used for all stented patients. Clinical parameters, stone demographics, operative time and postoperative events were analyzed.

Results

Seventy patients met the inclusion criteria. Mean stone size was 8.5 mm (SD 7.06), 68.49% were located in the renal pelvis and 31.51% were in the proximal ureter. Reasons of preoperative stenting were: 14 (19.18%) ureteral stricture, 17 (23.29%) urosepsis, 29 (39.73%) residual stones after a first intervention (stage procedure) and 13 (17.8%) unsuccessful extracorporeal shockwave lithotripsy. Mean operative time was 88 minutes (SD 37.20); 32 patients (45.71%) were stented and 38 (54.28%) were not. There were no significant differences in operative time (p = 0.85) or postoperative outcomes (p = 1).

Conclusions

A postoperative ureteral stent is not necessary after fURS using UAS in pre-stented patients.