The Post-Ureteroscopic Lesion Scale (PULS): a multicenter video-based evaluation of inter-rater reliability

Japanese survey of perioperative complications and ureteral stricture after ureteroscopy with laser lithotripsy for upper urinary tract stones in multicenter collaborative study

OBJECTIVES

This study aimed to investigate perioperative complications and the details of postoperative ureteral stricture after ureteroscopy with laser lithotripsy (URS-L) for upper urinary tract stones in Japan.

METHODS

Patient data on intra- and postoperative complications after ureteroscopy using URS-L were retrospectively collected from multiple centers in Japan between April 2017 and March 2020 with the cooperation of the Japanese Society of Endourology and Robotics. Data included the number of patients undergoing URS-L, number and type of intra- and postoperative complications, and detailed characteristics of postoperative ureteral stricture.

RESULTS

In total, 14 125 patients underwent URS-L over 3 years at 82 institutions. Annual URS-L numbers gradually increased from 4419 in 2017, to 4760 in 2018, and 4946 in 2019. The total complication rate was 10.5%, which was divided into intra-operative complications in 1.40% and postoperative complications in 9.18%. The annual incidences of intra- and postoperative complications were not significantly different from year to year (p = 0.314 and p = 0.112). Ureteral perforation, ureteral avulsion, and the intra-operative conversion rate were 1.35%, 0.03%, and 0.02%, respectively. Fever >38°C, septic shock, blood transfusion, and postoperative mortality were 7.44%, 0.81%, 0.07%, and 0.04%, respectively. Ureteral stricture occurred in 0.8% of cases. The median length of stricture site was 10.0 mm and the success rate of stricture treatment was 54.6%.

CONCLUSION

Although URS-L utilization has increased in Japan, the annual complication rate has remained steady. Although URS-L is a useful and less invasive procedure, devastating complications can still occur.

Post-Ureteroscopic Lesion Scale to determine ureteral wall damage, not so easy to employ

OBJECTIVE

To analyze the level of agreement of the Post-Ureteroscopy Lesion Scale (PULS) and the consequences on its application in clinical practice with more reliable statistical data than the one used in the original work.

METHODS

14 URS and 14 micro-URS were performed in 14 female porcine model. All the procedures were video recorded and an anatomopathological analysis was performed in each ureter. Sixteen urologists (9 endourologists and 7 general urologists) and 4 residents evaluated the ureteral lesions according to the PULS, with degrees 0, 1 and ≥2. The agreement was calculated with percentages, Kendall's W coefficient and the indicators Fleiss' Kappa and Krippendorff's Alpha, while the inter-rater agreement was calculated with Spearman's correlation and Cohen's Kappa.

RESULTS

The percent of agreement was 11.1%. The coefficients were likewise classified as low or very low, with the greatest agreement found among the inexperienced. Also, 50% of the raters did not agree with the rest.

CONCLUSIONS

The low inter-rater agreement, the specificity of the PULS and the clinical-pathological correlation suggests that this scale is not simple, and probably has a long learning curve.

Effect of bladder emptying status on the ureteral access sheath insertion resistance and following ureteral injury in RIRS: a prospective randomized controlled trial in academic hospital

PURPOSE

To evaluate the effect of bladder emptying status on the ureteral access sheath (UAS) insertion resistance and following ureteral injury.

METHODS

Eighty patients were enrolled and randomly divided into bladder emptying group and control group before UAS placement. A digital force gauge (Imada Z2-50N) was used to measure the resistance during the UAS insertion. The ureteral injury was evaluated and graded with Post-Ureteroscopic Lesion Scale (PULS) system at the end of procedure. The mean resistance, maximum resistance in different ureteral segments, and ureteral injury were compared between the two groups.

RESULTS

The mean resistance (3.12 ± 0.49 vs. 4.28 ± 0.52 N, P < 0.001), maximum resistance in the whole procedure (5.17 ± 0.72 vs. 6.39 ± 0.96 N, P < 0.001) and distal ureter (3.07 ± 0.75 vs. 6.18 ± 1.17 N, P < 0.001) in the bladder emptying group were significantly lower when compared to the control group. In subgroup analysis, the similar result was also noted in patients with BMI ≥ 25 when compared to patients with BMI < 25, while there was no significant difference between men and women, age ≥ 50 years versus age < 50 years. The incidence of PULS 1-2 ureteral injury in the bladder emptying group was lower than the control group (35% vs. 55%, P = 0.045). The ureteral injury in distal ureteral was less frequently noted in bladder emptying group than the control group (22.5% vs. 55%, P = 0.006); however, there was no significant difference in middle and upper ureter (P > 0.05).

CONCLUSION

Emptying the bladder before UAS insertion can effectively reduce the UAS insertion resistance and the risk of distal ureteral injury in RIRS.

Diagnostic value of Xpert® BC Detection, Bladder Epicheck®, Urovysion® FISH and cytology in the detection of upper urinary tract urothelial carcinoma

PURPOSE

Following the current guidelines, diagnosis and staging for upper urinary tract tumours (UTUC) can be performed with Computed Tomography, urography, ureterorenoscopy (URS) and selective cytology. The aim of the study was to evaluate the performance of the Xpert®-BC-Detection and the Bladder-Epicheck®-test in the detection of UTUC and compare it with cytology and the Urovysion®-FISH test using histology and URS as gold standard.

METHODS

A total of 97 analyses were collected through selective catheterization of the ureter before URS to test for cytology, Xpert®-BC-Detection, Bladder-Epicheck® and Urovysion®-FISH. Sensitivity, specificity, and predictive values were calculated using histology results/URS as reference.

RESULTS

Overall sensitivity was 100% for Xpert®-BC-Detection, 41.9% for cytology, 64.5% for Bladder-Epicheck® and 87.1% for Urovysion®-FISH. The sensitivity of Xpert®-BC-Detection was 100% in both, LG and HG tumours, sensitivity of cytology increased from 30.8% in LG to 100% in HG, for Bladder-Epicheck® from 57.7% in LG to 100% in HG and of Urovysion®-FISH from 84.6% in LG to 100% in HG tumours. Specificity was 4.5% for Xpert®-BC-Detection, 93.9% for cytology, 78.8% for Bladder-Epicheck® and 81.8% for Urovysion®-FISH. PPV was 33% for Xpert®-BC-Detection, 76.5% for cytology, 58.8% for Bladder-Epicheck® and 69.2% for Urovysion®FISH. NPV was 100% for Xpert®-BC-Detection, 77.5% for cytology, 82.5% for Bladder-Epicheck® and 93.1% for Urovysion®FISH.

CONCLUSION

Bladder-Epicheck® and Urovysion®FISH along with cytology could be a helpful ancillary method in the diagnosis and follow-up of UTUC while due to its low specificity Xpert®-BC Detection seems to be of limited usefulness.

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.

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.

Utility of Post-ureteroscopy Lesion Scale (PULS) in Per-operative Decision-Making for the Need of Double J Stent

Objectives: To assess the applicability of the post ureteroscopy lesion scale (PULS) as an objective measure to define the need for double J (DJ) stent placement after ureterorenoscopy (URS).

Methods: Between June and December 2020 a cross-sectional study was conducted at a university hospital. All patients fulfilling the inclusion criteria undergoing URS for renal or ureteric stones were included. At the completion of procedures, the ureter was carefully inspected for injury. Lesions were classified using PULS scoring by the operating surgeon, another consultant, and the resident. The primary outcome was to validate the PULS score against the surgeon’s decision for postoperative stenting and to assess its reliability. 

Results: A total of 126 patients were included with a mean age of 43.42±15.3 years. The mean stone size was 9.42±3.60mm. DJ stents were placed in 81 cases (62.4%). All of the 38 (30.1%) patients with a significant residual fragment were stented. Ureteric injury of grade 1 was observed in 66 patients (52.3%), of which 22 (33%) had DJ stenting. PULS grade 2 injuries were observed in 22 patients (17.4%), and 95% were stented. With a PULS score of > 2 almost all (97.8%) were stented. Inter-rater reliability of PULS scoring was high among the consultants (Kendall’s W=0.89, p<0.005).

Conclusion: DJ stent placement was observed in 33%, 95%, and 98% of patients with PULS grade 1, 2, and >2 injury respectively. In patients with no residual fragment, the need for DJ stenting can be objectively defined using the PULS scoring system as it has high specificity and good interrater reliability.

Xpert® bladder cancer detection as a diagnostic tool in upper urinary tract urothelial carcinoma: preliminary results

Objectives:

Upper urinary tract urothelial carcinoma (UTUC) represents about 5–10% of all urothelial malignancies with an increasing incidence. The standard diagnostic tools for the detection of UTUC are cytology, computed tomography (CT) urography, and ureterorenoscopy (URS). No biomarker to be included in the daily clinical practice has yet been identified. The aim of our study was to evaluate the potential role of Xpert® Bladder-Cancer (BC)-Detection in the diagnosis of UTUC.

Methods:

Eighty-two patients underwent 111 URS with Xpert® BC-Detection, cytology, or Urovysion® analysis of UT for suspicion of UTUC. Twenty-four cases were excluded from the analysis due to a non-diagnostic Xpert® BC-Detection, cytology, or Urovysion®. Samples were analyzed with upper tract (UT) urinary cytology, with Xpert® BC-Detection on UT urines, and with Urovysion® Fluorescence in situ hybridization (FISH) test. After urine collection, the patients underwent retrograde pyelography and/or URS, and if positive a UT biopsy. The Xpert® BC-Detection was reported by the software as negative or positive [cut-off total Linear Discriminant Analysis (LDA) = 0.45]. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of cytology, Xpert® BC-Detection and Urovysion-FISH were calculated using URS and/or histology results as reference.

Results:

In all, 27 (31%) of 87 URS resulted positive, with 20 low-grade (LG) and 7 high-grade (HG) tumors. Overall sensitivity was 51.9% for cytology, 100% for Xpert® BC-Detection, and 92.6% for Urovysion. The sensitivity of cytology increased from 26% in LG to 100% in HG tumors. For Xpert® BC-Detection, sensitivity was 100% both in LG and in HG, and for Urovysion-FISH, it increased from 90% in LG to 100% in HG tumors. PPV was 82.4% for cytology, 35% for Xpert® BC-Detection, and 73.5% for Urovysion. NPV was 81.4% for cytology, 100% for Xpert® BC-Detection, and 96.2% for Urovysion.

Conclusion:

The excellent NPV of Xpert® BC-Detection allows to avoid unnecessary endoscopic exploration of the UT, reducing invasiveness and URS complications in the follow-up of UTUC.

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.

Preoperative hydronephrosis is a predictive factor of ureteral stenosis after flexible ureteroscopy: a propensity scores matching analysis

Objectives

Ureteral stenosis is a serious complication of flexible ureteroscopy. How to predict the possibility of stricture before surgery is an important topic. This research retrospectively studied the influence of preoperative hydronephrosis on ureteral stenosis after flexible ureteroscopy, to explore whether the preoperative hydronephrosis could predict postoperative ureteral stenosis.

Methods

We conducted a retrospective study on patients who received flexible ureteroscopy in our hospital for upper ureteral calculi from January 2015 to June 2018. Patients were followed-up for 36 months after surgery, and intraoperative and postoperative complications were recorded. We divided patients into the mild hydronephrosis group and moderate to severe hydronephrosis group. Preoperative clinical baseline data of the patients were adjusted by propensity matching score analysis. Differences of intraoperative ureteral injury, operative time, postoperative ureteral stricture, and SFR one month after surgery was statistically analyzed. Kaplan–Meier’s method and Log-rank test were used to compare the differences in the cumulative incidence of ureteral stenosis between the two groups. Cox regression was used to compare the hazard ratio of ureteral stenosis between the two groups.

Results

A total of 447 patients with 469 sides surgery were included, including 349 sides in the mild hydronephrosis group and 120 sides in the moderate to severe hydronephrosis group. Twenty-nine patients with 30 sides developed ureteral stenosis. Before and after propensity, the incidence of ureteral stricture matching analysis was 6.4% and 8%, respectively. There were statistical differences in ureteral stricture and injury, but the statistical differences in SFR and operation time were inconsistent. Kaplan–Meier showed a significant difference in the cumulative incidence of ureteral stenosis between the two groups.

Conclusions

Patients with moderate to severe hydronephrosis before surgery were more likely to have an intraoperative ureteral injury and postoperative ureteral stricture after FRUS. Preoperative hydronephrosis is an important predictor of ureteral stricture.

Ureteral access sheath-related injuries vs. post-operative infections. Is sheath insertion always needed? A prospective randomized study to understand the lights and shadows of this practice

OBJECTIVE

To compare intraoperative ureteral injuries in RIRS with UAS insertion with the rate of postoperative infections after RIRS without UAS insertion.

PATIENTS AND METHODS

In this randomized trial, patients who received an indication for RIRS between January 2017 and December 2017 were divided into two groups. Group A had no UAS insertion and Group B had UAS insertion. Post-Ureteroscopic Lesion Scale (PULS) grading was performed after UAS or flexible ureteroscope removal. Proximal, middle and distal ureteral lesions were evaluated and compared according to the PULS scale. Additionally, patients in both groups were followed postoperatively to assess any infective complication.

RESULTS

The evaluation comprised 181 patients, 89 for group A and 92 for group B. Overall stone-free rate, clinically insignificant residual fragments, and final stone-free rate were 41.4%, 53.5%, and 95%, respectively. There were 33 (37.1%) patients with ureteral lesions in group A while 42 (45.6%) patients had ureteral lesions in group B, with no significant difference. On the other hand, the overall presence of postoperative infection rate was much higher for Group A (37.1% vs 16.3% P = 0.03).

CONCLUSIONS

UAS insertion does not result in a higher number of ureteral injuries. UAS insertion during RIRS allows a lower rate of postoperative infections.

CLINICAL TRIAL REGISTRATION NUMBER (ISRCTN REGISTRY NUMBER)

55546280.

Flexible Ureteroscopy for Treatment of Upper Urinary Tract Calculus

The aim of this article is to illustrate a step-by-step guide to flexible ureteroscopy (URS) for treatment of upper urinary tract calculus. Preoperative evaluation of the patient with focus on comorbidities is paramount for the type of stone procedure to be performed. In this article, the steps of operating room setup, patient positioning, gaining access to the upper urinary tract, flexible URS, laser lithotripsy, basket extraction of stone fragments, and placement of a ureteral stent are described. The importance of clearance of the ureter before flexible URS in the case of pre-existing ureteral stone is also described.

Ureteral access sheath-related injuries vs. post-operative infections. Is sheath insertion always needed? A prospective randomized study to understand the lights and shadows of this practice

OBJECTIVE

To compare intraoperative ureteral injuries in RIRS with UAS insertion with the rate of postoperative infections after RIRS without UAS insertion.

PATIENTS AND METHODS

In this randomized trial, patients who received an indication for RIRS between January 2017 and December 2017 were divided into two groups. Group A had no UAS insertion and Group B had UAS insertion. Post-Ureteroscopic Lesion Scale (PULS) grading was performed after UAS or flexible ureteroscope removal. Proximal, middle and distal ureteral lesions were evaluated and compared according to the PULS scale. Additionally, patients in both groups were followed postoperatively to assess any infective complication.

RESULTS

The evaluation comprised 181 patients, 89 for group A and 92 for group B. Overall stone-free rate, clinically insignificant residual fragments, and final stone-free rate were 41.4%, 53.5%, and 95%, respectively. There were 33 (37.1%) patients with ureteral lesions in group A while 42 (45.6%) patients had ureteral lesions in group B, with no significant difference. On the other hand, the overall presence of postoperative infection rate was much higher for Group A (37.1% vs 16.3% P=.03).

CONCLUSIONS

UAS insertion does not result in a higher number of ureteral injuries. UAS insertion during RIRS allows a lower rate of postoperative infections. Clinical Trial Registration Number (ISRCTN registry number): 55546280.

Atlas of scoring systems, grading tools and nomograms in Endourology: A comprehensive overview from The TOWER Endourological Society research group

INTRODUCTION

With an increase in the prevalence of kidney stone disease (KSD), there has been a universal drive to develop reliable and user-friendly tools such as grading systems and predictive nomograms. An atlas of scoring systems, grading tools and nomograms in Endourology is provided in this paper.

METHODS

A comprehensive search of world literature was performed to identify nomograms, grading systems and classification tools in endourology related to KSD. Each of these were reviewed by the authors and have been evaluated in a narrative format with details on those which are externally validated and their respective citation count on google scholar.

RESULTS

A total of 54 endourological tools have been described in our atlas of endourological scoring systems, grading tools and nomograms. Of the tools, 23 (43%) are published in the last 3 years showing an increasing interest in this area. This includes 5 for percutaneous nephrolithotomy (PCNL), 6 for flexible ureteroscopy (fURS), 3 for semi-rigid URS (sURS), 9 for shockwave lithotripsy (SWL), 2 for stent encrustations, 3 for intra-operative appearance at the time of URS and 3 to classify intra-operative ureteric injury. There were 3 tools for renal colic assessment, one each for prediction of future stone event, stone classification and stone impaction and 2 for need of emergency intervention in ureteric stone. While 2 tools are related to stone recurrence, 6 are related to post-procedural complications. There are now 2 tools for simulation in endourology and 5 for patient reported outcome measures (PROMS).

CONCLUSIONS

A number of reliable and established tools exist currently in endourology. Each of these offers their own respective advantages and disadvantages. While nomograms and scoring systems can help in the decision making, these must be tailored to individual patients based on their specific clinical scenarios, expectations and informed consent.

Diagnostic ureteroscopy for upper tract urothelial carcinoma: friend or foe?

Introduction

The European Association of Urology guidelines recommend offering kidney-sparing surgery (KSS) as a primary treatment option to patients with low-risk tumours. Cystoscopy, urinary cytology, and computed tomography urography (CTU) do not always allow correct disease staging and grading, and sometimes there is even a lack of certainty regarding the diagnosis of UTUC. Diagnostic ureteroscopy (d-URS) may therefore be of crucial importance within the diagnostic framework and fundamental in establishing the appropriate therapeutic approach.

Evidence acquisition and synthesis

A systematic review of the literature was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Risk of bias was assessed using Risk of Bias in Non-randomized Studies of interventions (ROBINS-I). Overall, from 3791 identified records, 186 full-text articles were assessed for eligibility. Finally, after a quantitative review of the selected literature, with the full agreement of all authors, 62 studies were considered relevant for this review.

Results

CTU has a sensitivity and specificity for UTUC of 92% and 95% respectively, but is not able to detect small or flat lesions with adequate accuracy. The sensitivity of voided urinary cytology for UTUC is around 67–76% and ranges from 43% to 78% for selective ureteric urine collection. As no technique offers a diagnosis of certainty, d-URS can allow an increase in diagnostic accuracy. In the present review the pros and cons of d-URS were analysed. This technique may provide additional information in the selection of patients suitable for neoadjuvant chemotherapy or KSS, distinguishing between normal tissue and low- and high-grade UTUC thanks to the emerging technologies.

Conclusions

Information obtainable from d-URS and ureteroscopic-guided biopsy can prove extremely valuable when the diagnosis of UTUC is doubtful or KSS is being considered. Notwithstanding concerns remain regarding the potential risk of bladder recurrence, cancer dissemination, and/or delay in radical treatment.

Abbreviations: CLE: confocal laser endomicroscopy; CSS: cancer-specific survival; CTU: CT urography; d-URS: diagnostic ureteroscopy; EAU: European Association of Urology; HR: hazard ratio; IMAGE1S: Storz professional imaging enhancement system; IVR: intravesical recurrence; KSS: kidney-sparing surgery; MFS: Metastasis-free survival; NAC: neoadjuvant chemotherapy; NBI: narrow-band imaging; OCT: optical coherence tomography; RFS: Recurrence-free survival; RNU: radical nephroureterectomy; ROBINS-I: Risk of Bias in Non-randomized Studies of interventions; URS(-GB): Ureteroscopy(-guided biopsy); UTUC: upper tract urothelial carcinoma; UUT: upper urinary tract

The feasibility of one-stage flexible ureteroscopy lithotripsy in solitary kidney patients with 1-3 cm renal stones and risk factors of renal function changes

Purpose

To compare perioperative outcomes and long-term renal function changes between prior stenting (PS) and not prior stenting (NPS) before flexible ureteroscopy lithotripsy (f-URS) for solitary kidney patients.

Methods

Solitary kidney patients with 10–30 mm renal stones were enrolled in this historical control study. Perioperative parameters and complications were compared. Stone-free was defined as the absence of any residual stones on a CT scan. Renal function changes were evaluated by estimated glomerular filtration rate (eGFR) and adjusted for body surface area. A decrease in the eGFR over 20% was identified as ‘deterioration’ in renal function. The follow-up period was at least 6 months. Logistic regression was used to identify risk factors of renal function deterioration.

Results

Of the 76 patients included, 40 cases experienced prior stenting before f-URS. The average stone diameter was 16.8 ± 4.7 mm, ranging from 10.0 to 28.4 mm. Initial SFR was 85.0 and 83.3% in the PS and NPS groups, respectively (p = 0.842), while SFR after the second procedure was 97.5 and 94.4% (p = 0.926). Seven PS and 5 NPS patients developed complications (p = 0.666). At the postoperative 6 months, seven patients showed a deteriorated renal function. Surgical time in minutes was identified as a risk factor for renal function deterioration after the operation (OR = 1.061, 95% CI: 1.015–1.109, p = 0.009, per minute).

Conclusion

It appears that one-stage f-URS without PS could be feasible for 10–30 mm renal stones in solitary kidney patients, and less surgical time might be beneficial to protect renal function.

Flexible ureteroscopy versus miniaturized percutaneous nephrolithotomy for renal stones of 1-2 cm

Technological advances and innovation in endourology have significantly reduced the indications of extracorporeal shockwave lithotripsy in the management of moderate-sized renal stones. In the last decade, we have witnessed a trend towards the use of finer scopes for percutaneous procedures instead of standard percutaneous nephrolithotomy (PCNL) (≥22 Fr). Miniaturized PCNL (mPCNL), i.e. miniPCNL (12–20 Fr), ultra-miniPCNL (11–13 Fr), mini-microPCNL (8 Fr), and microPCNL (<5 Fr), is increasingly being used. Concomitant developments in laser technology have provided a safe and effective stone fragmentation modality for use via flexible ureteroscopes (fURS). Technological advances in the design of fURS have improved not only the optics (fiber optic to chip-on-the-tip technology digital image) but also the ergonomics. Both the endourological techniques are extremely effective and safe, as shown in a multitude of good-quality studies. There are some differences in stone-free rate and complications. mPCNL in general has a higher stone-free rate, albeit with a slightly higher incidence of hemorrhagic complications. fURS often requires longer stenting time and longer period to achieve stone clearance, whereas mPCNL often needs ureteral catheter for only 24 hours and has a higher first day stone-free rate. fURS is a 1 day procedure compared to mPCNL, which requires patients to stay hospitalized for 2–3 days. It is therefore important to tailor the indications of these two procedures to the individual patient’s needs.

Consultation on kidney stones, Copenhagen 2019: aspects of intracorporeal lithotripsy in flexible ureterorenoscopy

Purpose

To summarize current knowledge on intracorporeal laser lithotripsy in flexible ureterorenoscopy (fURS), regarding basics of laser lithotripsy, technical aspects, stone clearance, lithotripsy strategies, laser technologies, endoscopes, and safety.

Methods

A scoping review approach was applied to search literature in PubMed, EMBASE, and Web of Science. Consensus was reached through discussions at the Consultation on Kidney Stones held in September 2019 in Copenhagen, Denmark.

Results and conclusions

Lasers are widely used for lithotripsy during fURS. The Holmium laser is still the predominant technology, and specific settings for dusting and fragmenting have evolved, which has expanded the role of fURS in stone management. Pulse modulation can increase stone ablation efficacy, possibly by minimizing stone retropulsion. Thulium fibre laser was recently introduced, and this technology may improve laser lithotripsy efficiency. Small fibres give better irrigation, accessibility, and efficiency. To achieve optimal results, laser settings should be adjusted for the individual stone. There is no consensus whether the fragmentation and basketing strategy is preferable to the dusting strategy for increasing stone-free rate. On the contrary, different stone scenarios call for different lithotripsy approaches. Furthermore, for large stone burdens, all laser settings and lithotripsy strategies must be applied to achieve optimal results. Technology for removing dust from the kidney should be in focus in future research and development. Safety concerns about fURS laser lithotripsy include high intrarenal pressures and temperatures, and measures to reduce both those aspects must be taken to avoid complications. Technology to control these parameters should be targeted in further studies.

Analysis of performance factors in 240 consecutive cases of robot-assisted flexible ureteroscopic stone treatment

Flexible ureteroscopy is the keystone of modern kidney stone treatment. Although a simple surgical technique achieves good clinical results and a low complication rate, there are high demands on the surgeon's dexterity and ergonomic restrictions. Robotic-assisted flexible ureteroscopy (rfURS) could overcome these limitations. After 4 years of use of rfURS at a tertiary stone center, performance factors were analyzed to define the role of rfURS in kidney stone management. A rfURS system was installed in August 2014 at the SLK Kliniken (Heilbronn, Germany). Treatment data of N = 240 consecutive patients undergoing rfURS were prospectively collected and analyzed. The patient cohort represents typical stone formers. N = 240 renal units containing 443 stones with an average stone load of 1798 mm³ were treated. Surgical parameters as well as the peri- and postoperative complications were recorded, analyzed and compared to the current data in the literature. OR time 91 min, stone treatment time 55 min, stone treatment efficacy 33 mm³/min; perioperative complications 5.4%; robot times: preparation 5 min, docking 5 min, console time to stone contact 6 min, console time 75 min; postoperative complications 6.7%; postoperative length of stay 1.5 days; stone-free rate (residuals < 2 mm) 90% and re-treatment rate 8.75%. This consecutive series represents real-life data about the utilization of rfURS. The detailed analysis of performance factors revealed the successful utilization of the first generation of robotic systems in endourologic stone surgery, and indicates that the robot performs comparably to conventional flexible URS. Optimal ergonomics maintain the surgeon's endurance in long-lasting surgeries.

Dusting, fragmenting, popcorning or dustmenting?

PURPOSE OF REVIEW

The present review identifies the latest scientific investigations within the fields of fragmenting and dusting to discuss optimizing treatment. In addition, new settings such as 'popcorning' are scrutinized carefully.

RECENT FINDINGS

During the past years, endoscopic techniques have continuously developed and changed the management of the treatment of kidney stones using ureteroscopy (URS). The most currently used energy source for stone disintegration is holmium laser lithotripsy. This technique offers different options for the surgeons to treat their patients suffering from kidney stones.

SUMMARY

URS with the holmium laser allows surgeons to use a variety of different strategies for treating urinary stones. There are two techniques which are most frequently used within this field: firstly fragmenting, using low frequencies and high pulse energy to break stones into small fragments before removal. On the other hand, dusting has been popularized in the field of endourology in recent years. This uses high frequencies and low pulse energy to form fine dust particles which then pass spontaneously down the ureter.

[Interrater reliability and clinical impact of the Post-Ureteroscopic Lesion Scale (PULS) grading system for ureteral lesions after ureteroscopy : Results of the German prospective multicenter BUSTER project]

BACKGROUND

The Post-ureteroscopic Lesion Scale (PULS) was designed as a standardized classification system for ureteral lesions after uretero(reno)scopy (URS). This study evaluates its routine use and a possible clinical impact based on a representative patient cohort.

MATERIALS AND METHODS

Data of 307 patients in 14 German centers within the BUSTER project were used to test 3 hypotheses (H): PULS score shows a high interrater reliability (IRR) after independent assessment by urologic surgeon and assistance personnel (H1); PULS score is correlated with the frequency of postoperative complications during hospital stay (H2); post-URS stenting of the ureter is associated with higher PULS scores (H3).

RESULTS

Median age of patients was 54.4 years (interquartile range [IQR] 44.4-65.8; 65.5% male). Median diameter of index stones was 6 mm (IQR 4-8) with 117 (38.4%) pyelo-caliceal and 188 (61.6%) ureteral stones. Overall, 70 and 82.4% of patients had pre-stenting and post-URS stenting, respectively. Stone-free status was achieved in 68.7% after one URS procedure with a complication rate of 10.8% (mostly grade 1-2 according to Clavien-Dindo). PULS scores 0, 1, 2 and 3 were assessed in 40%, 52.1%, 6.9% and 1% of patients, respectively, when estimated by urologic surgeons. PULS score showed a high IRR between the urologic surgeon and assistance personnel (κ = 0.883, p < 0.001), but was not significantly correlated with complications (ρ = 0.09, p = 0.881). In contrast, a significant positive correlation was found between PULS score and post-URS stenting (ρ = 0.287, p < 0.001). A PULS score of 1 multiplied the likelihood of post-URS stenting by 3.24 (95% confidence interval 1.43-7.34; p = 0.005) as opposed to PULS score 0.

CONCLUSIONS

Removal of upper urinary tract stones using URS is safe and efficacious. Real-world data provided by this study confirm a high IRR of the PULS score and its clinical impact on the indication for post-URS stenting. A future prospective randomized trial should evaluate a possible standardization of post-URS stenting based on PULS score assessment.

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.

How bothersome double-J ureteral stents are after semirigid and flexible ureteroscopy: a prospective single-institution observational study

PURPOSE

To evaluate in details the actual extent of double-J stent-related symptoms after semirigid (URS) and flexible (RIRS) ureteroscopy using a validated questionnaire.

METHODS

We asked to complete the Ureteric Stent Symptoms Questionnaire (USSQ) to all stone patients undergoing URS or RIRS with stent placement from 2010 to 2015. Stent-related symptoms' prevalence, severity, and impact on daily life were analyzed using descriptive statistics and five-order Likert scales. Subgroups analyses were performed.

RESULTS

232 patients completed the USSQ. Stents had a deep impact on urinary symptoms (daily frequency ≥ 1 per hour 59.1%, ≥ 1 nocturnal micturition 90.1%, urgency 86.6%, burning 82.3%) that represented a problem for 88.4% of patients. 83.2% complained of pain, mostly in the kidney (67.9%) or in the bladder area (31.3%), particularly during physical activity (72.9%) and micturition (77.0%). Pain interfered with everyday life in 92.2%. General health, working, and sexual activity were also affected. 62.0% of patients would be dissatisfied (51.6% unhappy or terrible) if further ureteral stenting was proposed in future. Younger patients and females were more affected. Limitations include observational design and lack of baseline evaluation.

CONCLUSIONS

Ureteral stents are responsible for significant urinary symptoms and pain after semirigid and flexible ureteroscopy. They also considerably affect general health, working and sexual activity. Urologists should consider it carefully before stenting, inform patients about stent-related symptoms, and minimize stent indwelling time.

Outcomes of ureteroscopy miniaturization on tissue damage and tissue hypoxia in a pig model

Miniaturization of ureteroscopy materials is intended to decrease tissue damage. However, tissue hypoxia and the gross and microscopic effects on tissue have not been adequately assessed. We compared the gross and microscopic effects of micro-ureteroscopy (m-URS) and conventional ureteroscopy (URS) on the urinary tract. We employed 14 pigs of the Large White race. URS was performed in one of the ureters with an 8/9.8 F ureteroscope, while a 4.85 F m-URS sheath was used in the contralateral ureter. Gross assessment of ureteral wall damage and ureteral orifice damage was performed. For microscopic assessment hematoxylin-eosin staining and immunohistochemistry for detection of tissue hypoxia were conducted. Regarding the macroscopic assessment of ureteral damage, substantial and significant differences were recorded using URS (C = 0.8), but not with m-URS. Microscopic assessment after staining with hematoxylin-eosin revealed greater epithelial desquamation in the URS group (p < 0.05). Pimonidazole staining revealed greater hypoxia in the epithelial cells than in the remainder of the ureteral layers. We conclude that m-URS causes less damage to the ureteral orifice than URS. Histopathological findings show m-URS reduces ureteral epithelial damage compared with conventional ureteroscopy. Both URS and m-URS cause cellular hypoxia.

Crowdsourcing Evaluation of Ureteroscopic Videos Using the Post-Ureteroscopic Lesion Scale to Assess Ureteral Injury

INTRODUCTION AND OBJECTIVES

We hypothesized that crowdsourcing assessments could be applied to the Postureteroscopic Lesion Scale (PULS) for ureteral injury.

METHODS

At a single institution, we prospectively digitally recorded 14 ureters at the terminal portion of standard ureteroscopic procedures. Each recording was reviewed by 10 global experts to determine a mean PULS score. Following training, the Crowd-Sourced Assessment of Technical Skills, C-SATS^® (C-SATS, Inc., Seattle, WA) platform was used to obtain crowd-based reviews. The mean crowd PULS scores was determined using the linear mixed-effects (LME) model. The intraclass correlation coefficient (ICC) was calculated to measure the agreement among experts. Spearman's rank correlation (rho) was used to quantify the strength of the relationship between the crowd LME mean and the experts.

RESULTS

Ten expert's reviews and 2100 layman reviews were obtained in 21 days and 49 hours, respectively. The ICC for the 10 experts was 0.68 (95% confidence interval 0.49, 0.86). When the expert mean PULS was <1, the crowd scored those recordings at 1 or greater. The highest scored recording by the experts was a 3.2, which the crowd scored at 2.25. The correlation between the crowd LME means and expert means across all videos was 0.70 (p = 0.0056) indicative of moderately strong agreement.

CONCLUSION

In this initial application of crowd-sourced evaluation of ureteral injury, there was a moderately strong correlation between crowd and expert ratings. Refinement of the training, through exposure to the nuances of ureteral injuries, in particular for PULS <1 or ≥3, may lead to better crowd/expert correlation. Compared to expert review, crowd data can be collected with much greater efficiency.

Preclinical Testing of a Combination Stone Basket and Ureteral Balloon to Extract Ureteral Stones

We have developed the Peralta Stone Extraction System to increase the safety of ureteral stone extraction. The device combines a nitinol stone basket and low-pressure balloon into a single device. After visualization, the stone is captured in the tipless nitinol basket and enveloped by a low-pressure balloon. We tested the performance of device prototypes in a porcine model using stone mimics with diameters ranging from 4.2 to 6.2 mm. Stones extracted with the device required less force when compared with stones in a standard ureteral stone basket. The force reduction was most pronounced for stones greater than 4.2 mm in diameter, and when traversing a ureteral stenosis model. In conclusion, a combination stone basket and balloon device may provide a new and safer way to extract ureteral stones.

Ureteroscopic Laser Lithotripsy: A Review of Dusting vs Fragmentation with Extraction

INTRODUCTION

Ureteroscopic laser lithotripsy is becoming the most commonly utilized treatment for patients with urinary calculi. The Holmium:YAG (yttrium aluminum garnet) laser is integral to the operation and is the preferred flexible intracorporeal lithotrite. In recent years, there has been increasing interest in examining the effect of varying the laser settings on the effectiveness of stone treatment. Herein, we review the two primary laser treatment approaches: dusting and fragmentation with extraction.

METHODS

We reviewed PubMed and MEDLINE databases from January 1976 through January 2017. All authors participated in the development of consensus definitions of dusting and fragmentation with extraction. The review protocol adhered to preferred reporting items for systematic reviews and meta-analyses (PRISMA) methodology.

RESULTS

When the Holmium:YAG laser is used to treat stones, there are two parameters that can be adjusted: power (J) and frequency (Hz). In one treatment paradigm, which became termed "fragmentation with extraction," laser settings that relied on high energy and low frequency were used. Another paradigm, which became termed "dusting," utilized low energy and high frequency settings, which had the effect of breaking off exceedingly small fragments from the stone.

CONCLUSIONS

Both dusting and fragmentation with extraction approaches to ureteroscopic stone treatment are effective. In fact, there is little evidence that one approach is better than the other. However, each does have relative advantages and disadvantages, which should be considered. Although dusting tends to be associated with shorter procedure times and a lower risk of ureteral damage, this approach may place the patient at increased risk for future stone events should all of the resultant debris not be expelled from the collecting system. The active removal associated with fragmentation with extraction, in contrast, may provide for a more complete initial stone clearance.

Risks of flexible ureterorenoscopy: pathophysiology and prevention

Currently, indications for flexible ureterorenoscopy (fURS) are expanding, mainly due to technological advancements. Although data from clinical series definitely presents fURS as a safe procedure, serious complications including sepsis and ureteral lesions do occur. These complications seem to be a result of the unique elements of fURS, ureteral access and irrigation, pushing normal upper urinary tract physiology into pathophysiological processes, including intrarenal/pyelo-veneous backflow and ureteral contractions, potentially resulting in septic, haemorrhagic and ureteral lesional complications. Knowledge on normal upper urinary tract physiology are crucial for understanding how these harmful effects of fURS may be avoided or minimized. The pathophysiology of intrarenal pressure increases and ureteral access will be discussed as a basis for understanding preventive measures. Role of antibiotics, ureteral access sheaths, safty guidewires, pain medication, prestenting and pharmacologic modulation of pyeloureteral dynamics are reviewed from a pathophysiological perspective.

Retrograde intrarenal surgery in the management of pediatric cystine stones

OBJECTIVE

To investigate the efficacy and safety of retrograde intrarenal surgery (RIRS) in the treatment of pediatric cystine stones.

STUDY DESIGN

Data of the pediatric patients who underwent RIRS for kidney stones were retrospectively evaluated. A total of 14 children with cystine stones managed with RIRS were identified. In addition to the patient demographics and stone characteristics, all retrospectively obtained operative data were evaluated and discussed in detail, with an emphasis on the success and complication rates.

RESULTS

Mean age of the 14 cases was 10.9 ± 2.2 years (range: 7-15). Mean stone size was 13.6 ± 2.4 mm (range: 10-18) (Summary table). Of these stones, four were located in the renal pelvis, three were in the lower, three were in the middle and the remaining four were located in upper calyx. Ureteral access sheath was used in 12 (85.7%) patients. The double-J ureteral stent was placed pre-operatively in one case and was inserted postoperatively in 12 cases. Mean operation time was 38.2 ± 7.2 min (range: 30-50). Complications were observed in two cases: mild ureteral laceration in the first and fever on the second postoperative day in the second patient. All of the patients were stone free on sonographic evaluation at the 4-week follow-up evaluation. Although potassium citrate treatment was initiated in 11 patients, tiopronin treatment was initiated in four patients for recurrence prophylaxis during long-term follow-up. During a mean follow-up period of 25.7 ± 5.2 months, stone recurrence was noted in one patient.

DISCUSSION

Treatment of patients with cystine stones is challenging, due to high risk of rapid recurrence in the presence of residual fragments. Besides allowing complete stone clearance in all cases in the current series, RIRS is a highly reproducible method that can be safely performed, even in recurrences. The major limitations of the current study were low number of patients and short follow-up period.

CONCLUSION

The results clearly indicated that RIRS is a safe treatment modality in the management of pediatric cystine stones.

Histopathological correlations to ureteral lesions visualized during ureteroscopy

Purpose

To correlate ureteral lesions visualized during ureteroscopy with histopathological findings.

Materials and methods

Ureteral access sheaths (UAS) sized 13/15 Fr. were inserted bilaterally in 22 laboratory pigs. During retraction of the UAS with a semirigid ureteroscope inside, ureteral lesions were evaluated and registered using the Post-ureteroscopic lesion scale (PULS). Ureters were excised in vivo between the uretero–pelvic junction and the uretero–vesical junction. Embedded in paraffin, 4-µm thick sections were step sectioned at 250–300 µm intervals and haematoxylin and eosin (HE) stained. Histopathological scoring of ureteral wall lesions was subsequently performed according to PULS.

Results

In 72.1% of ureters, the highest histopathological score was at least 1 grade higher than the highest endoscopic PULS score. For 12 (27.9%) lesions, the difference was 2 scores higher, and for 1 (2.3%), it was 3 scores higher. The histopathological PULS grade was higher than the endoscopical PULS grade at all minimum, quartile, and maximum scores. There was a significant difference in the distribution of highest lesional scores between the endoscopic and histopathological PULS (p = 0.002). The calculated mean of the highest scores was 1.49 for endoscopic PULS and 2.51 for histopathological PULS (p < 0.0001).

Conclusion

Histopathological evaluation of ureteral wall lesions after UAS placement revealed a significantly higher degree of severity than observed endoscopically. Thus, endoscopy underestimated the histopathological extent of the lesion in the majority of cases.

[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.

Pharmacological Relaxation of the Ureter When Using Ureteral Access Sheaths during Ureterorenoscopy: A Randomized Feasibility Study in a Porcine Model

Objective. High intraluminal pressure during ureterorenoscopy (URS) increases risk of infectious and haemorrhagic complications. Intrarenal pressure may be reduced by the use of ureteral access sheaths (UASs), which on the other hand may cause ureteral damage. We have previously shown that the β-agonist isoproterenol (ISO), when administered topically in the irrigation fluid, is able to inhibit ureteral muscle tone and lower intrarenal pressure during URS. The aim of this study was to examine the effect of ISO on the success rate of UAS insertion in a porcine model. Materials and Methods. 22 pigs in which a UAS could not initially be placed were randomized to endoluminal irrigation with either ISO (0.1 μg/mL) or saline before a new insertion trial. Subsequently, it was registered whether the UAS could be passed without resistance. During extraction of the sheath, any ureteral lesions were characterized ureteroscopically using the PULS classification system. Surgeons were blinded to randomization. Results. In the ISO group, the observed effect of irrigation was 63% successful UAS insertions, compared to 27% in the saline group. No serious lesions (<PULS grade 2) were observed in the ISO group. Conclusions. Endoluminal irrigation with ISO may facilitate UAS insertion and potentially decrease UAS related ureteral lesions.

Evaluating Ureteral Wall Injuries with Endoscopic Grading System and Analysis of the Predisposing Factors

OBJECTIVE

To analyze the predictive factors for intraoperative ureteral wall injury due to semirigid ureteroscopy (URS) used in the treatment of ureteral calculi.

METHODS

The data of 437 patients who had URS due to ureteral stones were prospectively analyzed. The ureteral wall injuries that occurred during URS were reviewed endoscopically at the end of surgery and divided into two groups as low grade (grades 0 and 1) and high grade (grades 2, 3, and 4) according to classification of ureteral wall injuries. Those two groups were compared for patient and stone characteristics and perioperative findings.

RESULTS

Ureteral wall injury was seen in 133 (30.4%) patients after surgery. According to the endoscopic classification of the lesions after URS, grades 0, 1, 2, and 3 injury were seen in 69.5%, 16.4%, 11.2%, and 2.7% of the patients, respectively. There were no grade 4 injuries in our series. Two groups showed statistically significant differences for the location (prox- vs distal and mid-ureter) and size of the stone (9.9 mm vs 14.03 mm), presence of preoperatively urinary tract infection (UTI) (12% vs 50.8%), needed balloon dilatation (9.8% vs 36.1%), duration of surgery (33.6 min vs 43.3 min), and surgical success rate (90% vs 76%) (p = 0.01, for all). Stone size, location, duration of surgery, and presence of preoperative infection were determined as independent prognostic factors for mucosal injury.

CONCLUSION

The ureteral wall injury grading system may be used for standardized reporting of ureteral lesions after ureteroscopy. Big, proximal ureteral stone, longer operation time, and presence of UTI are the risk factors for ureteral wall injury during URS.

Intraoperative Evaluation of Ureteral Access Sheath-Related Injuries Using Post-Ureteroscopic Lesion Scale

OBJECTIVE

In the present study, intraoperative ureteral injuries inflicted during retrograde intrarenal surgery (RIRS) with ureteral access sheath (UAS) use were evaluated using the Post- Ureteroscopic Lesion Scale (PULS).

MATERIALS AND METHODS

Patients in whom a UAS was used during RIRS and for whom ureter images were video recorded during the procedure were included in the study. PULS grading was performed after UAS removal, and video sequences of all patients were viewed by a junior resident, a senior resident, and four experienced urologists and assessed according to the PULS. Ureteral lesions in distal, middle, proximal, and multiple locations were evaluated and compared according to the PULS scale. The inter-rater reliability of PULS grading among various urologists was also evaluated.

RESULTS

The evaluation comprised 101 patients. In 77 patients, 9.5/11.5 French UAS devices were used, and in 24 patients, 12/14 French UAS devices were used. The stone-free rate, clinical insignificant residual fragments, and final stone-free rate were 41.6%, 53.5%, and 98%, respectively. In 58.4% of the patients, no lesions were present according to PULS grading. No lesions of Grade 3 and above were found; however, there were lesions of Grade 1 and 2 in 38.6% and 2.9% of the patients, respectively. Injuries were found in the proximal ureter only and distal ureter only in 45.23% and 40.47% of the patients, respectively. Multiple injuries occurred in 5.94% of the patients (in 3.96% in the proximal and distal ureter, in 0.99% in the mid- and distal ureter, and in 0,99% in the proximal, mid-, and distal ureter). In the grading performed according to the PULS classification, there was a high accuracy among the residents and specialists.

CONCLUSIONS

The assessment of UAS-induced injuries using standardized intraoperative methods will help to evaluate the procedure more objectively and will guide the postoperative follow-up of patients.

Impact of surgical experience on stone-free rates of ureteroscopy for single urinary calculi of the upper urinary tract: a matched-paired analysis of 600 patients

INTRODUCTION

To evaluate the impact of surgical experience on ureteroscopic stone-free rates (SFR) and complication rates (CR) for the treatment of urinary calculi of the upper urinary tract.

METHODS

We evaluated retrospectively, patients (n=300) having undergone ureteroscopy (URS) for single urinary calculi treated by residents (n=12) at our department over a 6-year period. These patients were matched according to age, gender, body-mass index, and stone side/size/site with patients (n=300) treated by consultants (n=5) of our department during the same period. Patient data, primary SFR, and CR were compared.

RESULTS

The mean±standard deviation (range) stone size was 6.39±3.26 (2-20) mm. The primary SFR after one URS procedure was 95.2% and did not differ between residents and consultants (95% vs 95.3%, p=0.489). The SFR were 95.9% and 98.5% for ureteral stones (p=0.125) and 93.2% and 89.3% for kidney stones (p=0.298) in the resident and consultant group, respectively. The SFR differed significantly between ureteral and kidney stones (97.2% vs 91.3%, p≤0.001). Perioperative complications occurred in a total of 63 patients (10.5%): Clavien 1: 3.8%, Clavien 2: 2%, Clavien 3a: 1.8%, and Clavien 3b: 2.8%, respectively. There were no differences in the total CR between residents (12%) and consultants (9%) (p=0.2116). However, the ureteral perforation rate was significantly higher in residents compared with consultants (4.3% vs 1.3%, p≤0.027).

CONCLUSIONS

URS is a safe and efficacious procedure for the treatment of single urinary calculi. Resident status does not compromise the SFR after ureteroscopic treatment of single urinary calculi. However, the incidence of ureteral perforation was associated with surgeon's experience.

Micro-ureteroscopy: Initial experience in the endoscopic treatment of pelvic ureteral lithiasis

OBJECTIVES

To present to report the first case of ureteral lithiasis resolved using a new endoscopic approach, which we call microureteroscopy (m-URS) and attempts to reduce the ureteral damage caused by conventional instrumentation.

MATERIAL AND METHODS

We selected a 53-year-old patient with a 16-mm calculus in the right distal ureter. For endoscopic access, we used a 4.8 Fr sheath from the microperc set and fragmented the stone with a 230-micron laser fiber.

RESULTS

Complete fragmentation of the stone was achieved. We placed a JJ catheter due to significant ureteral edema. The surgical time and postsurgical stay were 156minutes and 24hours, respectively. There were no complications, the requirements for analgesia were minimal, and the patient was free of residual stones.

CONCLUSIONS

The m-URS technique is feasible, simple and effective for the treatment of pelvic ureteral lithiasis in women and optimizes minimal invasion, with results that can be comparable to conventional endoscopic techniques in terms of ease of access and quality of endoscopic vision without affecting the resolution capacity. Larger studies and greater technological development is needed to define the definitive role of this procedure. Currently, its major limitations lie in the treatment of proximal ureter lithiasis and in the treatment of men. This technique could also be a viable alternative for pediatric patients.

Is Prolonged Operation Time a Predictor for the Occurrence of Complications in Ureteroscopy?

OBJECTIVE

To determine the impact of duration of ureteroscopy for urolithiasis on complication rates (CRs) of the procedure.

METHODS

A retrospective analysis of 2,010 patients, treated between 2006 and 2011, was done. The operation time (OT) and the occurrence of complications were compared.

RESULTS

The overall CR was 14.3% [298 complications, minor complications (Clavien I-II) 91.7%]. The median OT was 35 min [interquartile range (IQR) 20-61]. The OT differed significantly between those without complications [34 min (IQR 20-60)] and those with complications [45 min (IQR 25-76)] (p < 0.0001). The correlation between the OT and the occurrence of complications (r = -0.009648, p < 0.0001) was very weak and passed the level of significance (r = 0.2). The effect size was of minor relevance (Cohen's d = 0.27972).

CONCLUSIONS

Longer OT correlates significantly with a higher CR. The effect is however shown to be minor and the overall rate of complications, especially severe ones, is low.