Sky is no limit for ureteroscopy: extending the indications and special circumstances

Illumination matters part I: comparative analysis of light sources and illumination in flexible ureteroscopy-fundamental findings from a PEARLS analysis

PURPOSE

Illumination characteristics of flexible ureteroscopes have been evaluated in air, but not in saline, the native operative medium for endourology. The aim was to evaluate light properties of contemporary ureteroscopes in air versus saline, light distribution analysis, and color temperature.

METHODS

We evaluated the Storz Flex-Xc and Flex-X2s, Olympus V3 and P7, Pusen 7.5F and 9.2F, and OTU WiScope using a 3D printed black target board in-vitro model submerged in saline. A spectrometer was used for lux and color temperature measurements at different opening locations.

RESULTS

Illuminance was higher in saline compared to air (5679 vs. 5205 lx with Flex-Xc, p = 0.02). Illuminance in saline differed between ureteroscopes (ANOVA p < 0.001), with highest for the Flex-Xc at 100% brightness setting (5679 lx), followed by Pusen 9.2F (5280 lx), Flex-X2s (4613 lx), P7 (4371 lx), V3 (2374 lx), WiScope (582 lx) and finally Pusen 7.5F (255 lx). The same ranking was found at 50% brightness setting, with the highest ureteroscope illuminance value 34 times that of the scope with lowest illuminance. Most scopes had maximum illuminance off center, with skewness. Three scopes had two light sources, with one light source for all other scopes. Inter-scope comparisons revealed significant differences of color temperature (ANOVA p < 0.001).

CONCLUSION

The study demonstrates the presence of inhomogeneous light spread as well as large differences in illumination properties of ureteroscopes, possibly impacting on the performance of individual scopes in vivo. Additionally, the study suggests that future studies on illumination characteristics of flexible ureteroscopes should ideally be done in saline, and no longer in air.

Retrograde intrarenal surgery with central neuraxial blockade versus general anesthesia: A systematic review and meta-analysis

Objective

The aim of the article is to assess the impact of retrograde intrarenal surgery under central neuraxial blockade in comparison to general anesthesia (GA).

Material and Methodology

This systematic review was conducted following the guidelines set out by the preferred reporting items for systematic reviews and meta-analyses. We conducted a comprehensive search across major electronic databases, including various types of studies such as descriptive studies and full-text literature, all of which were incorporated into the current review from 2018 to 2023. We involved those studies, which included the comparative study of spinal anesthesia (SA), epidural anesthesia (EA), and combined spinal epidural anesthesia with GA.

Result

In our meta-analysis of 12 studies, it was found that anesthesia technique significantly affected operation time, with neuraxial anesthesia (NA) showing a mean difference of -2.28 (95% confidence interval (CI): -3.5 to -1.04, P = 0.003) compared to GA. However, there were no significant differences in rates of stone clearance, 24-h pain scores and length of hospital stay among patients administered with NA or GA for retrograde intrarenal surgery (RIRS).

Conclusion

On the basis of the outcomes of study, NA can serve as a viable alternative to GA for RIRS. Our analysis reveals no significant differences in rates of stone clearance, operation duration, 24-h pain scores, complication rates, and length of hospital stay between NA in addition to GA in the context of RIRS. This suggests that given the potential economic advantages, NA might be a preferable choice over GA, contingent on patient preferences, baseline characteristics, and stone burden.

Preference for diagnosing and treating renal colic during pregnancy: a survey among Chinese urologists

To explore the preference for diagnosing and treating renal colic during pregnancy among Chinese urologists. A questionnaire was designed using the Sojump® platform. WeChat, the largest social networking platform in China, was used to distribute the questionnaire to urologists at hospitals of all levels in China. In total, 110 responses were included. Of the respondents, 100.0% used ultrasound to diagnose renal colic during pregnancy, followed by magnetic resonance imaging (17.3%) and low-dose CT (3.6%). Phloroglucinol (80.9%) and progesterone (72.7%) were the most commonly used antispasmodics and analgesics. Opioid analgesics were not commonly used (12.7%). Most of the respondents (63.6%) indicated that no more than 20% of the patients needed surgical intervention. If surgery was unavoidable, 95.5% preferred temporary renal drainage, including ureteral stenting (92.7%) and percutaneous nephrostomy (2.7%). However, some respondents still preferred definitive stone treatment, such as ureteroscopy lithotripsy (3.6%) and percutaneous nephrolithotomy (0.9%). Moreover, there were no differences in the choices of urologists with different professional titles regarding diagnostic tools, most therapeutic medications, or surgical methods (p > 0.05). Ultrasound is the preferred tool for diagnosing renal colic during pregnancy. Low-dose CT is still not widely accepted. Pregnant patients with renal colic are initially treated conservatively. Urologists prefer ureteral stenting when there are clinical indications for intervention.

Single use flexible ureteroscopes: Current status and future directions

Introduction

Single use ureteroscopes are a technological innovation that have become available in the past decade and gained increased popularity. To this end, there are now an increasing number of both benchside and clinical studies reporting outcomes associated with their use. Our aim was to deliver a narrative review in order to provide an overview of this new technology.

Methods

A narrative review was performed to gain overview of the history of the technology's development, equipment specifications and to highlight potential advantages and disadvantages.

Results

Findings from preclinical studies highlight potenial advantages in terms of the design of single use ureteroscopes such as the lower weight and more recent modifications such as pressure control. However, concerns regarding plastic waste and environmental impact still remain unanswered. Clinical studies reveal them to have a non inferior status for outcomes such as stone free rate. However, the volume of evidence, especially in terms of randomised trials remains limited. From a cost perspective, study conclusions are still conflicting and centres are recommended to perform their own micro cost analyses.

Conclusions

Most clinical outcomes for single use ureteroscopes currently match those achieved by reusable ureteroscopes but the data pool is still limited. Areas of continued debate include their environmental impact and cost efficiency.

Comparative evaluation of urolithiasis management options in patients with horseshoe kidney: A systematic review and meta-analysis

Background

Horseshoe kidney is a rare congenital anomaly commonly complicated by urolithiasis. Extracorporeal shockwave lithotripsy (ESWL), ureteroscopy (URS), and percutaneous nephrolithotomy (PCNL) are treatment options for horseshoe kidney stones. The aim of this systematic review is to compare the benefits and risks of these management options.

Methods

MEDLINE, EMBASE, and Cochrane Library databases were searched from inception to February 2022. A total of 516 nonduplicate studies were screened against the inclusion and exclusion criteria. Studies comparing at least 2 interventions with ≥10 patients per intervention were included.

Results

Nine retrospective observational studies published from 2007 to 2021 with a total of 565 patients were included. Reported mean ± SD or mean (range) stone sizes ranged between 17.90 ± 2.43 mm and 27.9 ± 8.6 mm for PCNL, 8.4 (2-25) mm and 22.3 ± 9.1 mm for URS, and 11.9 ± 2.0 mm and 16.8 ± 4.4 mm for ESWL. There was no difference in single-session and overall stone-free rate (SFR) between PCNL and URS, with a risk ratio of 1.04 (95% confidence interval, 0.95-1.13; I2 = 20.63%). Ureteroscopy had better stone clearance than ESWL, with an overall SFR risk ratio of 1.38 (95% confidence interval, 1.04-1.82; I2 = 0%). There was no statistically significant difference in overall SFR between PCNL and ESWL. Most patients who underwent URS and ESWL experienced Clavien-Dindo (CD) grade I-II complications. Percutaneous nephrolithotomy was associated with the highest complication rates, including 5 CD grade III and 3 CD grade IV complications and a mean postoperative hemoglobin drop of 0.47 to 1.83 g/dL. There were no CD grade V complications across all studies.

Conclusions

There was no difference in SFR between PCNL and URS. Ureteroscopy was associated with a smaller stone burden and fewer and less severe complications. Ureteroscopy was found to be more effective than ESWL with a higher SFR and comparable safety profile. Further large-scale randomized controlled trials are needed to confirm these findings.

Analysis of uroseptic shock after ureteroscopy for ureteral calculi during pregnancy: a case report

BACKGROUND

Uroseptic shock secondary to ureteral calculi during pregnancy is rare. It is characterized by rapid onset, rapid progression, aggressive disease, limited treatment, poor prognosis, and a mortality rate higher than 20% with improper or delayed management. A clear diagnosis is made based on typical clinical symptoms and abdominal ultrasound, often requiring combined multidisciplinary treatment and the simultaneous release of the obstruction. The high mortality rate is mainly related to inappropriate early treatment of stones and infections or failure to intervene in a timely manner.

CASE PRESENTATION

A 21-year-old first-time pregnant patient with uroseptic shock was admitted to our intensive care unit. The patient was successfully treated at our hospital with multidisciplinary cooperation, high-dose vasoactive drugs, IABP, CRRT, VA-ECMO, and termination of pregnancy.

CONCLUSIONS

Timely relief of obstructions, termination of pregnancy, and the provision of IABP, CRRT, and VA-ECMO when necessary in critically ill patients with uroseptic shock during pregnancy can improve the success rate of resuscitation.

Minimally invasive nephrolithotomy versus retrograde intrarenal surgery in surgical management of Lower calyceal stones: a systematic review with meta-analysis

OBJECTIVE

The efficacy and safety of minimally invasive nephrolithotomy (MPCNL) versus retrograde intrarenal surgery (RIRS) was assessed for lower calyceal (LC) stones.

METHODS

Our team conducted a systematic literature search up to December, 2022, using PUBMED, EMBASE and the Cochrane Library. The study was registered in PROSPERO, CRD 42021247197. Randomized controlled trials evaluating the efficacy and safety of MPCNL versus RIRS for LC stones were collected. Heterogeneity among the studies was assessed using the χ 2 test based on the Q and I2 tests. Pooled effect sizes were calculated using a fixed model if I2 is less than 50%; otherwise, a random-effects model was chosen. The primary outcomes were the 3-month stone-free rate (3SFR) and total complications, while the secondary outcomes were the operating time, hospital stay, haemoglobin reduction, bleeding, postoperative fever and complications with the Clavien-Dindo system. A subgroup analysis of 10-20 mm LC stones was also designed.

RESULTS

A total of 7 peer-reviewed trials comprising 711 patients were identified. No statistical differences were observed in the heterogeneity results of the 3SFR or total complications ( P >0.1, I2 < 50%). Compared with RIRS, MPCNL had an unfavourable safety profile, resulting in total complications [odds ratio (OR): 1.87 (95% CI: 1.05, 3.33); P =0.03], haemoglobin reduction [OR: 0.81 (95% CI: 0.15, 1.47); P =0.02] and complications with Grade I [OR: 5.52 (95% CI: 1.34, 22.83); P =0.02] but an improved efficacy and 3SFR [OR: 2.43 (95% CI: 1.48, 3.97); P =0.0004]. As for the 10-20 mm LC stones, compared with RIRS, MPCNL also had an unfavourable safety profile, resulting in total complications [OR: 2.47 (95% CI: 1.20, 5.07); P =0.01], complications with Grade I [OR: 4.97 (95% CI: 0.99, 25.01); P =0.05] and an increased hospital stay [OR: 2.46 (95% CI: 2.26, 2.66); P =0.00001] but an improved efficacy and 3SFR {OR: 3.10 (95% CI: 1.61, 5.99); P =0.0008]. The efficacy effect of MPCNL and safety effect of RIRS were nearly equal for both stones sized less than 20 mm (number needed to treat = 17, number needed to harm = 20) and stones sized 10-20 mm (number needed to treat = 20, number needed to harm = 13). No statistical difference was found between the MPCNL and RIRS groups for the rest of outcomes.

CONCLUSION

Both MPCNL and RIRS are safe and effective management methods. Moreover, compared with RIRS, MPCNL had an unfavourable safety profile but improved efficacy for LC stones of ≤20 mm or 10-20 mm, and the differences were statistically significant. The relative profit of efficacy of MPCNL was similar to the relative profit of safety of RIRS.

Unfavorable factors in accessing the pelvicalyceal system during retrograde flexible ureteroscopy (fURS)

Flexible ureteroscopy (fURS) is a well-established procedure for treating multiple upper-urinary tract pathologies, particularly renoureteral lithiasis. Endoscopes have undergone significant advancements, including miniaturization, improved optics, and increased maneuverability. In addition, advancements in accessory instruments, such as the performance of laser fibers, guidewires, and extraction probes, have played a significant role in improving the overall performance of flexible ureteroscopy procedures. However, despite these advancements, unique circumstances can make achieving optimum results during flexible ureteroscopy challenging. These include congenital renal anomalies (horseshoe kidneys, ectopic kidneys, rotation anomalies), as well as the unique intrarenal anatomy (infundibulopelvic angle, infundibular length) or the specifications of the endoscope in terms of maneuverability (active and passive deflection). This review explored challenging scenarios during flexible ureteroscopy procedures in the pyelocaliceal system.

Understanding the ablation rate of Holmium:YAG and thulium fiber lasers. Perspectives from an in vitro study

This study sought to analyze the ablation rates of Holmium:YAG (Ho:YAG) and thulium fiber laser (TFL) under different settings combinations. Lasering was carried out by a computed spiral pattern through a stepper motor bearing a laser fiber. BegoStones were placed inside a water container and lasered therein and the ablation rate was calculated. Different combinations were tested for ~12 Watts (W) for Ho:YAG and TFL lasers. Further 25 W combination for TFL were conducted testing higher frequencies. One-hundred-one experiments were conducted. Under ~12 W, the highest ablation rate for Ho:YAG was obtained with 40 Hz/0.3 J, and Virtual Basket™ (VB) emission mode [114.35 (88.30 - 126.40) mg/min] whereas for TFL, using 40 Hz/0.3 J, and long pulse [143.40 (137.40 - 146) mg/min]. A matched-comparison for 12 Hz/1 J settings showed that TFL outperformed Ho:YAG using medium pulse [63.30 (55.30 - 81.30) vs 132.00 (115.70 - 228.60) mg/min, p=0.016] and long pulse [62.90 (51.60 - 78.90) vs 134.70 (110.60 - 149.30) mg/min, p=0.016]. In the 40 Hz/0.3 J settings, TFL outperformed Ho:YAG (p=0.034). Nonetheless, Ho:YAG with VB's ablation rate increased [114.35 (88.30 - 126.40)], being comparable to that of TFL with medium pulse [127.5 (88.90 - 141.70)] (p=0.400). In TFL 25 W experiments, the ablation rate of 500 Hz / 0.05 J, was higher than those of 1000 Hz / 0.025 J (p=0.049). TFL ablation rate is higher than that of Ho:YAG. Moreover, the Virtual Basket™ emission mode, increased Ho:YAG ablation rates, resulting reaching similar to that of TFL in certain modalities.

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

BACKGROUND

Endourologic interventions for urolithiasis in patients with anomalous kidneys can be challenging, and comparisons between these interventions are not well studied. We aim to compare the safety, outcomes and complications of retrograde intrarenal surgery (RIRS) versus percutaneous nephrolithotomy (PCNL) in patients with urolithiasis in anomalous kidneys.

METHODS

A propensity score-matched pair analysis (PSM) was performed on pooled patient data from 20 centers. 569 patients with anomalous kidneys (horseshoe kidney [HSK], ectopic kidney, malrotated kidney) and urolithiasis who received either PCNL or RIRS as the primary modality of intervention from 2010 to 2020 were analyzed. Patients were matched based on calculated propensity scores by a regression model using age, sex, comorbidities, stone size, and renal anomaly type as co-variates. Multivariate logistic regression of factors (mode of treatment [PCNL or RIRS], comorbidities, stone size) and their effects on outcomes of stone-free rate (SFR), need to abandon surgery due to intraoperative difficulty, postoperative hematuria and sepsis and were analyzed when applicable.

RESULTS

After PSM, there were a total of 127 pairs in each group. Overall, PCNL conferred a higher SFR compared to RIRS (OR=3.69, 95% CI 1.91-7.46, P<0.001), particularly in HSK (OR=3.33, 95% CI 1.22-9.99, P=0.023), and ectopic kidneys (OR=18.10, 95% CI 3.62-147.63, P=0.002), with no significant difference in malrotated kidneys. There was no significant difference in postoperative sepsis observed. Surgery was abandoned more often in RIRS than PCNL (6.3% vs. 0%, P=0.014). Although PSM provides a robust analysis due to baseline differences in the unmatched cohorts, this study was limited by an inevitable degree of selection bias.

CONCLUSIONS

While both modalities are safe and efficacious, PCNL yields better SFR than RIRS in patients with anomalous kidneys, with no difference in postoperative sepsis rates. Patients may benefit from personalized management best carried out in high volume endourology centers.

Retrograde Intrarenal Surgery Versus Miniaturized Percutaneous Nephrolithotomy for Kidney Stones >1cm: A Systematic Review and Meta-analysis of Randomized Trials

CONTEXT

Although miniaturized percutaneous nephrolithotomy (mPCNL) and retrograde intrarenal surgery (RIRS) are both options for treating >1cm kidney stones, controversies exist on whether one is more effective and safer than the other.

OBJECTIVE

To systematically appraise randomized trials comparing the effectiveness and safety of mPCNL and RIRS for treating >1cm kidney stones.

EVIDENCE ACQUISITION

A systematic search on PubMed/Medline, Web of Science, Embase, and ClinicalTrials.gov was conducted in August 2020 following the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA). Randomized trials comparing mPCNL and RIRS for >1cm kidney stones, and reporting stone-free rate (SFR), hemoglobin drop, transfusion rate, length of hospital stay (LOS), and/or complications, were included.

EVIDENCE SYNTHESIS

Eight studies compared mPCNL and RIRS, but one was not included due to its high risk of bias. SFR was higher for mPCNL (RR: 1.06 [95% coefficient interval {CI}, 1.01-1.10], p=0.008). Hemoglobin drop was higher for mPCNL (mean difference [MD]: 0.35 [95% CI, 0.05-0.65] g/dl, p=0.02); however, transfusion rates were similar (p=0.44). Complication rate was similar between mPCNL and RIRS (p=0.39), and the LOS was higher for mPCNL (MD: 1.11 [95% CI, 0.06-2.16] d, p=0.04). A subgroup analysis of lower pole stones showed that SFR was higher for mPCNL (RR: 1.09 [95% CI, 1.00-1.19], p=0.05).

CONCLUSIONS

Both approaches are effective and safe. Among these approaches, mPCNL has a higher SFR than RIRS for overall >1cm renal and lower pole stones, but longer LOS, and a higher hemoglobin drop that does not translate into higher transfusion rates. Complications are comparable.

PATIENT SUMMARY

Randomized trials have evaluated whether miniaturized percutaneous nephrolithotomy (mPCNL) or retrograde intrarenal surgery is more effective and safer for treating >1cm stones. After comparing the stone-free rate, hemoglobin drop, transfusion rate, length of hospital stay, and complications between both the approaches, mPCNL was found to be slightly more effective, but both were equally safe.

Variables measured on three-dimensional computed tomography are preferred for predicting the outcomes of shock wave lithotripsy

PURPOSE

Shock wave lithotripsy (SWL) is used to treat upper urinary tract stones. Recently, some volume analyzers have enabled preoperative assessment using three-dimensional computed tomography (3D-CT). We evaluated the efficacy of 3D-CT variables for predicting the outcomes of SWL.

METHODS

The study population included 193 patients who underwent SWL between November 2014 and August 2020. In addition to conventional two-dimensional computed tomography (2D-CT) assessments, 3D-CT assessments of targeted stones were retrospectively performed, and stone size and stone density (SD) were measured. The successful and unsuccessful treatment groups were compared and risk factors for an unsuccessful first SWL session were investigated. The predictive accuracy of variables measured on 3D-CT was evaluated by receiver operating characteristic curves and multivariate analyses.

RESULTS

The success rate of the first SWL session was 73.1%. Stone volume, mean SD and highest SD on 3D-CT were significantly higher in the unsuccessful group than in the successful group. Stone volume showed a higher area under the curve (AUC) than the estimated volumetric stone burden and stone diameter, which were measured on 2D-CT (0.729, 0.683, and 0.672, respectively). The AUCs of the mean SD and highest SD on 3D-CT were higher than those on 2D-CT (0.699, 0.680, 0.617, and 0.627, respectively). Multivariate analyses identified stone volume (≥ 0.29 ml), mean SD on 3D-CT (≥ 421 HU), and absence of hydronephrosis as independent predictive factors for unsuccessful SWL.

CONCLUSION

3D-CT variables were promising predictors of the outcomes of SWL. Preoperative 3D-CT assessment is helpful for selecting favorable patients for SWL.

Single-use ureteroscopes in ectopic pelvic kidney stones

We analyzed the results of single-use flexible ureteroscopy (su-fURS) with the holmium laser in treating renal stones associated with ectopic pelvic kidney (EPK). The study retrospectively analyzed data of 11 patients diagnosed with EPK and stone disease who underwent su-fURS between May 2017 and November 2019. The analyzed surgical data included the mean operation time, stone-free and complication rates, as well as hospitalization period. Disposable digital flexible ureteroscopes were exclusively used. The mean age was 55, with a 1.2:1 male to female ratio. The mean stone burden was 30±9 mm (ranging from 17 to 49 mm). The mean calculi digitized surface area (DSA) was 299±56 mm² (ranging from 170 to 597 mm²). A ureteral access sheath was used in all 11 patients, and holmium laser lithotripsy was performed (dusting mode parameters: low energy – 0.5J, high frequency – 50 Hz, long pulse; pop-corn mode: high energy >1 J, medium frequency– 10–50 Hz, long pulse; fragmenting mode: high energy >1 J, low frequency <10 Hz, short pulse). The average operative time was 78±19 minutes (ranging from 68 to 144 minutes). The stone-free status (residual fragments <3 mm) after one session was 60.1%, 84.1% after the second session, and 94.4% after the third session. The hospitalization period was 29 hours (ranging from 17 to 39 hours). The overall complications rate (according to the Clavien-Dindo system) was 19.7%. Therefore, su-fURS represents an effective therapeutic approach characterized by a remarkably high stone-free rate and few complications in EPK-associated calculi.

Modified Takazawa anatomical classification of renal pelvicalyceal system based on three-dimensional virtual reconstruction models

Background

Previous classification of renal pelvicalyceal anatomical structure may be difficult to intuitively understand and unpractical for endourological surgery. We aim to put forward a modified Takazawa anatomical classification of renal pelvicalyceal system based on three-dimensional (3D) virtual reconstruction models for endourological surgery.

Methods

We retrospectively collected data on 225 patients (320 kidneys) in total between Apr. 2017 and Dec. 2020, spatial anatomical structure of renal pelvis and calyces were modeled and corresponding morphological parameters were measured after 3D virtual reconstruction of computed tomography urography (CTU). The modified Takazawa renal pelvicalyceal anatomical classification was advanced based on the renal pelvicalyceal morphological parameters [bifurcated branches of renal pelvis, cross sectional area of renal pelvis and ureteropelvic junction (UPJ), infundibuloureteral angle (IUA), lower pole infundibular calyceal length (IL)] by 3D virtual reconstruction models, and comparison of renal pelvicalyceal system morphological parameters were performed to evaluate the differences in various classification types of renal pelvis and calyces.

Results

Anatomical structure of renal pelvis and calyces were divided into two main types (Type A and Type B) according to renal pelvic branch patterns. A single pelvis without bifurcated branch was regarded as Type A (62%) and subclassified into three subtypes: Type A1 (22%), Type A2 (27%) and Type A3 (13%), the slimline pelvis was classified as Type A1, the typical pelvis as Type A2 and the broad pelvis as Type A3. A divided pelvis with bifurcated branches was seen as Type B (38%) and subclassified into two subtypes: Type B1 (15%) with the wide and flat lower calyx branch, Type B2 (23%) with the narrow and steep lower calyx branch.

Conclusions

Previous studies have reported that the visualization and classification of renal pelvicalyceal anatomical structure by endocast, autopsy, ultrasonography and excretory urography, the modified Takazawa classification system based on 3D virtual reconstruction models enables to standardized different anatomical morphology of renal pelvicalyceal system and provide intuitive and concise information on anatomy, thus leading to the improvement in treatment modality.

Intraoperative and postoperative surgical complications after ureteroscopy, retrograde intrarenal surgery, and percutaneous nephrolithotomy: a systematic review

INTRODUCTION

Retrograde ureteroscopy (URS), intra-renal surgery (RIRS) and percutaneous nephrolithotomy (PCNL) represent routine interventions for the treatment of ureteral and renal stones, although at times associated with serious adverse events. Of note, the evidence on perioperative complications after these procedures remains sparse and controversial. Moreover, there is a lack of standardized reporting of adverse events using uniform systems. The aim of the present study was to systematically review of the available evidence on URS/RIRS and PCNL for the surgical treatment of urinary stone, assessing the incidence of intra- and postoperative events, classified according to the modified Clavien-Dindo scale.

EVIDENCE ACQUISITION

A systematic review of the literature was performed according to PRISMA recommendations and was conducted on intra- and postoperative complications, as well as on their management, following URS, RIRS and PCNL procedures, particularly focusing on major events.

EVIDENCE SYNTHESIS

Overall, 26 studies (13 on URS/RIRS and 11 on PCNL) met the inclusion criteria and were evaluated. The highest intraoperative complication rate was 11.5% and 8.5% for RIRS and PCNL, respectively. Major complication rate following URS/RIRS and PCNL ranged between 0.3-31.7% and 2-17.1%, respectively. The most frequent adverse events were obstructive pyelonephritis or urinary leakage requiring the placement of a double J stent or a drainage. Among PCNLs series, life-threatening adverse events have also been reported, including bleeding requiring renal angioembolization and urothorax.

CONCLUSIONS

Despite the inclusion of series using a standardized reporting system, the complication rate after URS/RIRS/PCNL remains extensively heterogeneous in the literature; in addition, a non-negligible proportion of studies did not characterize the adverse events nor report the actual management strategy to solve them. Future research is needed to standardize the classification and reporting of surgical complications after endourological procedures (taking into consideration the surgeon's experience and skills), aiming to improve patient counseling and potentially the strategy for their prevention.

Spinal versus general anesthesia during retrograde intra-renal surgery: A propensity score matching analysis

Background:

The indications for retrograde intra-renal surgery (RIRS) have greatly increased, however, there is still no consensus on the use of spinal anesthesia (SA) during this procedure. The aim of this study was to evaluate the comparability of surgical conditions and outcomes with RIRS performed under SA versus general anesthesia (GA) for renal stones.

Materials and methods:

This was a prospective, observational study in patients scheduled for RIRS in a single teaching hospital in Italy. Inclusion criteria were age >18 years and the presence of single or multiple renal stones. We recorded information concerning the site of lithiasis, the number of calculi, total stone burden, and the presence of concomitant ureteral stones or hydronephrosis. A propensity score-matched analysis was performed to evaluate the results in terms of surgical outcome, intraoperative and postoperative complications, and analgesia demand balanced for confounding factors. Patients were followed-up until day 90 from discharge.

Results:

We included 120 patients, the propensity score-matched cohort included 40 patients in the SA and 40 in the GA groups. The stone-free rate was 67.5% in the GA group and 70.0% in the SA group (p = 0.81). The use of auxiliary procedures within 90 days did not differ between groups (25.0% vs. 22.5%, p = 0.79). No cases of conversion from SA to GA were recorded. We did not find any differences in intraoperative bleedings, perforations, and abortions. Complication rates were similar in the 2 groups (10.0% in GA vs. 5.0% in SA, p = 0.64).

Conclusions:

In our cohort, RIRS performed under SA and GA was equivalent in terms of surgical results and complications.

Precision Stone Surgery: Current Status of Miniaturized Percutaneous Nephrolithotomy

PURPOSE OF REVIEW

Innovations in lasers and surgical technology have led to a renewed interest in the miniaturization of percutaneous nephrolithotomy (PCNL). We review the different approaches and evidence on the efficacy of mini-PCNL.

RECENT FINDINGS

Mini-PCNL encompasses a range of techniques using tract sizes from 4.8 to 22 F to treat renal stones. The most common device uses irrigation to passively extract stones out of the sheath. Super-mini-PCNL incorporates active suction. Ultra- and micro-techniques reduce the tract to smaller diameters. Laser fragmentation is the main lithotripsy modality. Studies demonstrate an association with reduced complications, hospital stay, and increased tubeless rate. Drawbacks include longer operative times while stone-free rates for larger stones may be sub-optimal. Mini-PCNL has advantages of less trauma and the avoidance of nephrostomy tubes. Ambulatory surgery is feasible in select patients. Advances in laser lithotripsy and active suction have the potential to improve stone clearance and treat larger stones.

How does pre-operative antimicrobial treatment influence the intra-operative culture results and infectious complications in patients with positive baseline bladder urine culture undergoing ureteroscopic lithotripsy?

We investigated how pre-operative antimicrobial treatment influenced intra-operative culture (IC) results and infectious complications in patients with positive pre-operative bladder urine culture (PBUC) undergoing ureteroscopic lithotripsy. We assessed 162 patients undergoing ureteroscopic lithotripsy from April 2019 to March 2020. Based on PBUC findings, they were divided into positive and negative PBUC groups. We administered pre-operative antimicrobial treatment to the positive PBUC group and only peri-operative antimicrobial prophylaxis to the negative PBUC group. We examined intra-operative cultures (ICs), including bladder urine culture, renal pelvic urine culture and stone culture, in all cases. We studied the association between the results of PBUC, ICs and infectious complications in both groups. A total of 67 and 95 patients had positive and negative PBUC, respectively. In the positive PBUC group, 19 (28.4%) patients still had positive bladder urine culture after the antibiotic treatment. Positive ICs (43.3% vs. 3.2%, p < 0.001) and post-operative fever (16.4% vs. 2.0%, p = 0.001) were more common in the positive PBUC group than in the negative PBUC group. In the positive PBUC group, 11 patients had a post-operative fever, regardless of the ICs results (6 positive ICs and 5 negative ICs). Furthermore, antimicrobial-resistant bacteria were detected from ICs in 5 patients with positive PBUC, including 4 suffering from a post-operative fever. Although the effect of pre-operative antimicrobial treatment is not definitive, to avoid serious infectious complications, we should recognize high-risk patients and perform more careful infection control based on the pre- and intra-operative culture results.

Urological issues in pregnancy: A review for urologists

Urological issues in the pregnant patient present a unique clinical dilemma. These patients may be challenging to treat due to risks associated with medications and surgical procedures. This review aims to provide an update on the physiological changes and surgical risks in pregnancy. In addition, we review the approach for management of urolithiasis and urinary tract infections in pregnancy. Lastly, we highlight the importance of a multidisciplinary approach to placenta percreta, a condition not commonly addressed in urological education.

Semirigid Ureteroscopy: Step by Step

This article aims to demonstrate a step-by-step technique of semirigid ureteroscopy (URS) for the treatment of ureteral stones, urothelial tumors, and ureteral stenosis. Operating room setup, camera settings, access to the bladder, and negotiation of the ureteral orifice, lasertripsy, basketing of the stone fragments, endoscopic treatment of ureteral tumors and ureteral stenosis, flexible URS at the end of semirigid URS, and Double-J stent placement are described step by step.

Antibacterial effect of fosfomycin tromethamine on the bacteria inside urinary infection stones

OBJECTIVE

This study sought to evaluate the antibacterial effect of fosfomycin tromethamine (FT) on the bacteria inside urinary infection stones.

METHODS

The internal structures of urinary stones were observed via scanning electron microscopy to verify the presence of internal bacteria. We randomly assigned equal numbers of patients with kidney stones who met the inclusion criteria into two groups in a prospective study and treated them with different perioperative antibiotics. One group (experimental group) was treated with FT, and the other (control group) was treated with cefuroxime sodium. All stone specimens were collected via percutaneous nephrolithotomy (PCNL). The primary infection stones were screened via a stone component analysis, 30 cases in the experimental group and 31 cases in the control group. High-performance liquid chromatography (HPLC)-mass spectrometry was used to measure the drug concentration inside the stones, the bacterial count was calculated via stone culture, and the clinical infection index were monitored for between-group comparisons.

RESULTS

Compared with the control group, the experimental group had a higher internal drug concentration, a higher drug sensitivity against various pathogenic bacteria, a lower bacterial colony count in the stone culture, and a lower incidence of postoperative clinical infection.

CONCLUSIONS

FT is more effective than cefuroxime, which is commonly used during the perioperative period of urinary stones, and exerts a high antibacterial effect on these internal bacteria, and effectively reduces the probability of infection and sepsis after urinary stone surgery. FT can be used as an antibiotic during the perioperative period of urinary stones.

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.

Outcomes of ureteroscopy for stone disease in anomalous kidneys: a systematic review

Introduction

Treatment of stone disease in anomalous kidneys can be challenging. As ureteroscopy (URS) has advanced, the number of studies reporting on outcomes of URS for stone disease in anomalous kidneys has increased. Our objective was to perform a systematic review of the literature to evaluate the outcomes of URS for stone disease in this group of patients.

Methods

A Cochrane style review was performed in accordance with the PRISMA guidelines using Medline, EMBASE, CINAHL, Cochrane Library, Scopus and individual urologic journals for all English language articles between inception and June 2018.

Results

Fourteen papers (413 patients) with a mean age of 43 years and a male to female ratio of 285:128 were included. The underlying renal anomaly was horseshoe kidney (n = 204), ectopic kidney (n = 117), malrotation (n = 86), cross fused ectopia (n = 2) and others (n = 2). With a mean stone size of 16 mm (range 2–35 mm), the majority of stones were in the lower pole (n = 143, 34.6%) or renal pelvis (n = 128, 31.0%), with 18.9% (n = 78) having stones in multiple locations. Treatment modality included the use of flexible ureteroscope in 90% of patients and ureteral access sheath used in 11 studies. With a mean operative time of 61.3 min (range 14–185 min), the initial and final SFR was 76.6% (n = 322) and 82.3% (n = 340), respectively. The overall complication rate was 17.2% (n = 71), of which 14.8% were Clavien I/II and the remaining 2.4% were Clavien ≥ III complications.

Conclusion

Although ureteroscopy in patients with anomalous kidneys can be technically challenging, advancements in endourological techniques have made it a safe and effective procedure. In these patients the stone-free rates are good with a low risk of major complications.

Infectious Complications After Laser Vaporization of Urinary Stones During Retrograde Intrarenal Surgery Are Not Associated with Spreading of Bacteria into Irrigation Fluid but with Previous Use of Fluoroquinolones

BACKGROUND

The pathogenesis of infectious complications after retrograde intrarenal surgery (RIRS) is not fully understood.

OBJECTIVE

To evaluate spreading of bacteria into irrigation fluid and blood during RIRS for stone management and to correlate such spreading with infectious complications.

DESIGN, SETTING, AND PARTICIPANTS

From January to December 2017, 38 patients who underwent RIRS for stones in two urological units were enrolled in this prospective, longitudinal cohort study.

INTERVENTION

A urine culture was taken before surgery and antimicrobial prophylaxis was given in line with the European Association of Urology guidelines. Blood and irrigation fluid samples were collected at the start of the endoscopic procedure and every 30min during the procedure. All samples were microbiologically examined and findings were compared with clinical data.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSES

Symptomatic and asymptomatic urinary tract infectious complications were correlated with microbiological and clinical data, using Student t test or Mann-Whitney U test.

RESULTS AND LIMITATIONS

Ten patients showed significant bacterial growth in irrigation fluid samples (seven Escherichia coli, two Klebsiella pneumoniae, and one Pseudomonas aeruginosa). Eight patients (21%) got febrile urinary tract infections during hospital stay: two had bacterial growth in the irrigation fluid (25%) and one also had bacteremia (12.5%). No correlation was found either between the bacterial growth in the irrigation fluid samples and the urine cultures that were taken before the procedure, or between the bacterial growth in the irrigation fluid samples and the development of postoperative infectious complications. Previous use of fluoroquinolones and a history of urinary tract infections were associated with infectious complications after RIRS.

CONCLUSIONS

We demonstrated spreading of bacteria into the irrigation fluid during RIRS procedures, but this spreading was not associated with the development of infectious complications. Particular attention should be given to previous antibiotic treatment before administration of antimicrobial prophylaxis.

PATIENT SUMMARY

Bacterial spreading into irrigation fluid is a common finding during retrograde intrarenal surgery, but it is not associated with infectious complications after the procedure. Particular attention should be given to previous antibiotic treatment before administration of antimicrobial prophylaxis.

The significance of intraoperative renal pelvic urine and stone cultures for patients at a high risk of post-ureteroscopy systemic inflammatory response syndrome

We examined the renal pelvic urine culture (RPUC) and stone culture (SC) during ureteroscopy and evaluated their associations with postoperative systemic inflammatory response syndrome (SIRS). We prospectively collected data of 224 patients who underwent ureteroscopic laser lithotripsy from March 2015 to December 2017. We examined the bladder urine culture pre-operatively. If the patients had positive culture results, we treated them with antibiotics for 5-7 days before surgery based on the sensitivity profile. We collected RPUC and SC samples during surgery. After ureteroscopy, patients were closely monitored for any signs of SIRS. Using a logistic regression model, we analyzed how the clinical factors affected the incidence of SIRS. Pre-operative bladder urine culture (PBUC) was positive in 111 patients (49.6%). Intraoperative RPUC was positive in 43 patients (19.2%), and SC was positive in 34 patients (15.2%). Postoperatively, 23 patients (10.3%) were diagnosed with SIRS. A multivariate analysis revealed that female gender, struvite calculi and positive intraoperative RPUC results were significantly associated with postoperative SIRS. Among the 31 patients who were positive for both PBUC and intraoperative RPUC, the pathogens were not consistent in 11 patients (35.5%). Among the 25 patients who were positive for both PBUC and intraoperative SC, the pathogens were not consistent in 13 patients (52.0%). We recommend collecting RPUC and SC samples during ureteroscopy, especially for patients with high risk factors, including female gender, expected struvite calculi and positive PBUC results.

Single-use disposable digital flexible ureteroscopes: an ex vivo assessment and cost analysis

OBJECTIVE

To assess and measure the capability of a single-use disposable digital flexible ureteroscope, the LithoVue™ (Boston Scientific, Marlborough, MA, USA), and to assess if there is a benefit to switching to single-use scopes.

PATIENTS AND METHODS

The LithoVue was compared to two commonly used reusable flexible ureteroscopes (Olympus URF-V [Olympus, Tokyo, Japan] and Karl Storz Flex-X^c [Karl Storz & Co. KG, Tuttlingen, Germany]) ex vivo. An analysis of reusable ureteroscope usage was performed to evaluate damage, durability, and maintenance costs. This was then compared to the projected costs of using single-use disposable scopes.

RESULTS

Flexion, deflection and irrigation flow of the LithoVue was equivalent, if not better than the reusable flexible ureteroscopes. An analysis of 234 procedures with seven new Olympus URF-V scopes, revealed 15 scope damages. Staghorn stones and lower pole/mid-zone stones were significant risk factors for damage (P = 0.014). Once damage occurred it was likely to occur again. Total repair costs were $162 628 (Australian dollars) (£92 411 in Great British pounds), the mean cost per case was $695 (£395). Factoring in the purchase cost, cleaning and repair costs, the cumulative cost of 28 reusable flexible ureteroscopy procedures was ~$50 000 (£28 412). If the LithoVue was priced at $1 200 (£682), switching to a single-use scope would cost ~$35 000 (£19 888).

CONCLUSION

The LithoVue is analogous to reusable flexible ureteroscopes in regard to standard technical metrics. Depending on its purchase cost it may also represent a cost saving for hospitals when compared to the cumulative costs of maintaining reusable scopes. Additionally, urologist may consider using the scope in cases in which reusable scope damage is anticipated.

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.

Italian endourological panorama: results from a national survey

Introduction

The purpose of this survey was to explore the dissemination of flexible ureteroscopy (fURS), shockwave lithotripsy (SWL) and percutaneous nephrolithotomy (PCNL) in the Italian urological community and to know the real availability of the complex endourological armamentarium all over the country.

Materials and methods

An online questionnaire characterizing the case volume/year of upper urinary tract stone treatment and the availability of flexible ureteroscopes (FUs) armamentarium was sent to all urological Italian centers.

Results

The survey was sent to 294 urological centers and 146 responded (49.7%). The case volume/year of fURS was the following: <20 cases in 20 centers (13.7%); 20-50 cases in 40 centers (27.4%), >50- <100 cases in 55 centers (37.8%) and >100 cases in 28 centers (19.2%). The case volume/year of SWL was the following: <50 cases in 18 centers (12.3%); >50- <200 cases in 56 centers (36.4%) and >200 cases in 35 centers (24%). In 37 centers (25.3%) SWL was not utilized at all. The case volume/year of PCNL was the following: <10 cases in 20 centers (14%); >10 - <30 cases in 55 centers (30%), >30- < 50 cases in 33 centers(23%), >50- <100 cases in 13 centers (9%) and >100 procedures in 2 centers (1%). However, 24 centers (16%) did not perform any PCNL procedure.Four centers (3%) did not have any FU at the moment of the survey. The availability of FUs was as follows: 1 FU in 21 (14%) centers, 2 FUs in 61 (42%) centers, 3 FUs in 29 (20%) centers, 4 FUs in 13 (9%) centers and ≥5 FUs in 16 (9%) centers. Only 82 (56%) centers had all of their FUs in working condition.

Conclusions

This survey succeeded in providing a complete overview on the Italian endourological panorama.

Proposal for a Simple Anatomical Classification of the Pelvicaliceal System for Endoscopic Surgery

We herein propose a nomenclature for renal calices and anatomical classification of the renal pelvis for endoscopic surgery. We prospectively collected data on a total of 270 patients (540 kidneys) who underwent CT-urography. We then constructed three-dimensional images of the renal pelvis and examined their morphologic classification. Forty-eight kidneys were excluded from this study because of severe hydronephrosis or large renal cysts. The remaining 492 kidneys were included. We systematically categorized each minor calix into five levels: top, upper, middle, lower, and bottom. The upper, middle, and lower calices were typically found in pairs: anterior and posterior. The most common total number of minor calices was eight (51%), followed by seven (30%). We also classified the form of the pelvis into type I: single pelvis (58%) and type II: divided pelvis (42%), according to the branch patterns of the renal pelvis. In type II, the renal pelvis is always bifurcated into the upper branch (top and upper) and lower branch (middle, lower, and bottom). Type I was subclassified into three types: type Ia (43%), the standard type; type Ib (4%), with a wide pelvis; and type Ic (11%), with a narrow pelvis. This anatomical classification can divide the renal pelvis into two major types (subdivided into four types) and name each minor calix. This simple classification enables to share common intrarenal information, thus leading to the development of concrete treatment strategies.

Predictive risk factors for systemic inflammatory response syndrome following ureteroscopic laser lithotripsy

The objective of this study was to investigate risk factors for the development of systemic inflammatory response syndrome following ureteroscopic laser lithotripsy. We retrospectively collected data of 469 patients who underwent ureteroscopic laser lithotripsy at our single institution from February 2008 to June 2016. Details for the patient, the stone, and the surgical factors that potentially contributed to postoperative infection were extracted. Using a logistic regression model, we analyzed how the clinical factors affected the incidence of systemic inflammatory response syndrome. Twenty-seven patients (5.7%) were postoperatively diagnosed with systemic inflammatory response syndrome; of these, 25 patients were diagnosed within 24 h after ureteroscopy. One patient required intensive care unit admission, but no death was reported. A preoperative stent was significantly associated with postoperative systemic inflammatory response syndrome only on univariate analysis, and the reasons for stenting were varied. Multivariate analysis revealed that obstructive pyelonephritis, a positive preoperative bladder urine culture result, and female gender were significantly associated with postoperative systemic inflammatory response syndrome. Patients who experienced obstructive pyelonephritis preceding ureteroscopic laser lithotripsy or had a positive preoperative bladder urine culture result were at an increased risk of systemic inflammatory response syndrome despite receiving appropriate preoperative antibiotic therapy. Regarding the impact of a preoperative stent on postoperative infection, further investigation focusing on reasons for stenting is needed.

A prospective multicenter European study on flexible ureterorenoscopy for the management of renal stone

Purpose

The aim of this study was to describe the outcomes and the complications of retrograde intrarenal surgery (RIRS) for renal stones in a multi-institutional working group.

Materials and Methods

From 2012 to 2014, we conducted a prospective study including all RIRS performed for kidney stones in 4 European centers. Demographic information, disease characteristics, and perioperative and postoperative data were gathered. Patients and stone data, procedure characteristics, results and safety outcomes were analyzed and compared by descriptive statistics. Complications were reported using the standardized Clavien system.

Results

Three hundred and fifty-six patients underwent 377 RIRS with holmium laser lithotripsy for renal stones. The RIRS was completed in all patients with a mean operative time of 63.5 min. The stone-free status was confirmed endoscopically and through fluoroscopic imaging after the first procedure in 73.6%. The second procedure was performed in twenty patients (5.6%) achieving an overall stone free rate of 78.9%. The overall complication rate was 15.1%. Intra-operative and post-operative complications were seen in 24 (6.7%) and 30 (8.4%) cases, respectively.

Conclusions

RIRS is a minimally invasive procedure with good results in terms of stone-free and complications rate.

RIRS in the elderly: Is it feasible and safe?

BACKGROUND

The aim of this study was to compare the safety and efficacy of RIRS in men ≥65 years to those <65 years.

MATERIALS AND METHODS

Patients who underwent RIRS were prospectively collected from March 2013 to March 2014 in 5 European centers. Perioperative outcomes and complications in elderly men were compared with men <65 years. Univariable and multivariable analyses were performed for factors predicting overall complications. The groups were compared using Mann-Whitney U test. Categorical variables were compared using chi-squared test and the Yates correction or the Fisher's exact test.

RESULTS

A total of 399 patients with renal stones were included, 308 (77.19%) were aged <65 years, 91 (22.8%) were aged ≥65 years. Elderly patients were more likely to have higher ASA scores (35.7% vs 92.3%; p < 001), Charlson Comorbidity Index (1.8 vs. 5.2, p < 0.001), hyperlipidemia (10.06% vs. 30.76%; p = 0,0005) and coronary heart disease (5.51% vs. 17.58; p = 0.005) compared to younger cohort. Perioperative outcomes (stone free rate, operative time and re-intervention rate) did not show differences between the two groups (p > 0.05). Surgical and medical complication rates were similar between the cohorts (14.28% vs 9.89%; p = 0.38). Multivariate analysis did not identify any predictive factors of complications among the two groups (p > 0.05).

CONCLUSIONS

In this study, elderly RIRS patients had comparable short term efficacy and perioperative complications to younger patients, despite a higher prevalence of comorbidity. Age itself should not be considered as a risk factor for the development of complications in patients undergoing RIRS for renal stone.

Ureteroscopic skills with and without Roboflex Avicenna in the K-box® simulator

Introduction

The aim of this study was to evaluate the acquisition of basic ureteroscopic skills with and without Roboflex Avicenna by subjects with no prior surgical training.

Material and methods

Ten medical students were divided in two groups: Group 1 was trained with Roboflex Avicenna and Group 2 with flexible ureteroscope alone, using the K-box^® simulator model. Participants were scored on their ability to perform or not two exercises, recording the time. In addition, the participants were evaluated on the quality of their performance for the following parameters: respect of the surrounding environment, flow of the operation, orientation, vision centering and stability.

Results

The first exercise was completed only by three and four out of five of students in Group 1 and Group 2, respectively. Stability with the scope was significantly more accurate in the first group compared with the second (P = 0.02). There were no differences in timing, flow or orientation between groups. Although not significant, a tendency of respecting the surrounding tissue and maintaining centered vision was perceived more in the first group. As for the second exercise, there were no differences between groups in regard of orientation, flow, respecting the surrounding tissue, stability or the ability of maintaining centered vision. Although not significant, the second group had a tendency of performing the exercise faster.

Conclusions

According to these preliminary results, the acquisition of basic ureteroscopic skills with and without robotic fURS in the K-box^® simulator, by subjects with no prior surgical training, is similar.

Reperfusion and Compartment Syndrome After Flexible Ureteroscopy in a Patient with an Iliac Vascular Graft

Background: Flexible ureteroscopy (fURS) is one of the main treatment options for urolithiasis less than 2 cm. Although fURS has no relative contraindication, some anatomical factors may need to be considered, as not all patients are suitable for the regular lithotomy position (LP). We report the case of a patient with a right iliac vascular graft that after an fURS without intraoperative incidences developed a reperfusion syndrome of the right lower limb.

Case Presentation: A 46-year-old male patient was referred for treatment and follow-up in the cystinuric clinic after being found to have a 3 cm pelvic stone with a Double-J catheter in place after two failed sessions of shockwave lithotripsy. The patient was placed in the LP and a standard ureteroscopy was done with no intraoperative complications. During the first hour in the recovery room, the patient developed severe pain in the right calf muscle stiffness, edema, and increased volume. A postreperfusion and compartment syndrome diagnosis was made with emergency fasciotomy.

Conclusion: To perform fURS, each case must be assessed individually. If a patient with an iliac vascular graft has to undergo fURS, the patient positioning must be modified by keeping the ipsilateral (or both) legs straight to avoid graft complications.

Recent advances in understanding and managing urolithiasis

During the last few years, there has been relevant progress in both understanding and managing urolithiasis. Our knowledge of stone formation has changed; although the importance of urine biochemistry was questioned by several investigators years ago, the decisive role of cellular processes (induced by oxidative stress) and the renal papilla has only recently been generally accepted as the most important step in stone formation. For calcium oxalate urolithiasis, the formation of papillary calcifications plays a key role and is of prognostic relevance. Further research has to concentrate on these aspects of preventing urolithiasis. Stone prevention (metaphylaxis) is a major issue when considering the burden it places on healthcare systems. An effective metaphylaxis could lower the cost of stone therapy significantly. For uric acid urolithiasis, so far there is only preliminary information available showing that papillary plaques are not as important as they are in calcium oxalate urolithiasis. Concerning stone management, endourology has improved stone therapy significantly during the last few years. Morbidity decreased and success (stone-free) rates increased. Therefore, the indications for extracorporeal shockwave lithotripsy (ESWL) narrowed. ESWL, however, still has its place in stone therapy. There is not one single treatment modality that is equally effective for all situations. It is important to observe the differential indications for different stones depending on size, localization, and composition.

Renal colic during pregnancy: Diagnostic and therapeutic aspects. Literature review

Introduction

Renal colic during pregnancy is a rare urgency but is one of the most common non-obstetric reasons for hospital admission. The management often means a challenge for the urologist and gynecologist due to the complexity involved in preserving the maternal and fetal well-being.

Material and methods

We performed a literature search within the PubMed database. We found 65 related articles in English. We selected 36 for this review prioritizing publications in the last two decades.

Results

The anatomical and functional changes of the genitourinary system during pregnancy are well documented; also during pregnancy, there are several metabolic pro-lithogenic factors. The most common clinical presentation is flank pain accompanied by micro or macro hematuria. US provides data identifying renal obstruction shown by an increased renal resistance index. MRI allows differentiating the physiological dilatation from the pathological caused by an obstructive stone showing peripheral renal edema and renal enlargement. Low dose CT has been determined to be a safe and highly accurate imaging technique. Once the diagnosis is confirmed, the initial management of patients should be conservative. When conservative management fails the interventional treatment is mandatory, a urinary diversion of the obstructed renal unit either by a JJ stent or through a PCN catheter has to be done. The definitive management of the stone can be done in the postpartum or deferred ureteroscopy can be considered during pregnancy.

Conclusions

Renal colic during pregnancy is an uncommon urgency, so it is important for the urologist to know the management of this condition.

The Use of Apnea During Ureteroscopy

OBJECTIVE

To describe and discuss the feasibility and the use of apnea during retrograde intrarenal surgery (RIRS).

MATERIALS AND METHODS

A discussion of the current literature about the different anesthesia techniques and the use of apnea to improve RIRS by avoiding renal movements over diaphragmatic excursion was performed.

RESULTS

To date, there are no mentions in the literature about the use of apnea as a mechanism to facilitate this procedure that requires extremely precise laser use. A description of the feasibility of apnea during RIRS is described as a technical consideration and discussed.

CONCLUSION

The use of apnea during RIRS has facilitated the procedure, avoiding renal movements, particularly in special cases where extremely precise maneuvers during laser use are required.

A Fatal Mycotic Sepsis after Retrograde Intrarenal Surgery: A Case Report and Literature Review

Purpose

The retrograde intrarenal surgery (RIRS) is a procedure that sees an increase in its use every day and is supported by excellent results in terms of safety and feasibility. We report the first case of fatal mycotic septic complication in a neurological patient for renal stone disease.

Case Presentation

The case of a woman 44 year-old, with left solitary kidney and history of advanced multiple sclerosis, epilepsy, bedridden and percutaneous endoscopic gastrostomy was described. She was hospitalized for the presence of recurrent lower urinary tract infections. The computed tomography (CT) scan control revealed a 1.7 cm obstructive renal pelvic stone and multiple stones in the bladder. After the refusal of a percutaneous approach, a RIRS was planned and done. No intraoperative complications were observed. In the postoperative period, she developed a urinary sepsis with progressive deterioration of the general conditions. She died 6 days after the RIRS for septic shock with a blood culture positive for Candida glabrata.

Discussion

A Pubmed search for fatal complications after RIRS shows only two cases not fully elucidated.

Conclusions

The use of flexible ureteroscopes and holmium lasers has a high succes rate;nevertheless, the possibility of a major complication should be kept in mind in order to evaluate all the risk factors, to adopt all the preventive measures for the safety of the patients.

Comparison of New Single-Use Digital Flexible Ureteroscope Versus Nondisposable Fiber Optic and Digital Ureteroscope in a Cadaveric Model

Purpose: To evaluate LithoVue, the new single-use digital flexible ureteroscope, in a human cadaveric model and compare it with a nondisposable fiber optic and digital flexible ureteroscopes.

Materials and Methods: LithoVue, a conventional fiber optic, and digital flexible ureteroscopes were each tested in four renal units of recently deceased female cadavers by three surgeons. The following parameters were analyzed: accessibility to the kidney and navigation of the entire collecting system with and without ureteral access sheath (UAS), lower pole access measuring the deflection of the ureteroscope with the working channel empty, and with inside two different baskets and laser fibers. A subjective evaluation of maneuverability and visibility was assessed by each surgeon at the end of every procedure.

Results: Kidney access into the Renal unit 1 was not possible without UAS for all ureteroscopes because of noncompliant ureter at the level of sacroiliac joint. The reusable digital ureteroscope was unable to reach one calix of the lower pole and one calix of the upper pole (Renal units 2 and 3) without UAS placement. Lower pole access with baskets and laser fibers was possible for each ureteroscope after UAS placement. No statistically significant differences were detected in angle deflection between ureteroscopes. The digital ureteroscope was preferred for visibility in all procedures: LithoVue for maneuverability in six procedures, fiber optic in five procedures, and the digital ureteroscope in one procedure.

Conclusions: LithoVue seems to be comparable with conventional ureteroscopes in terms of visibility and manipulation into the collecting system in fresh human cadavers. Further studies in humans are needed to determine the clinical value of this new instrument.

Current Standard Technique for Modern Flexible Ureteroscopy: Tips and Tricks

BACKGROUND

Thanks to advancements in the endoscopic armamentarium, flexible ureteroscopy (fURS) has become a viable and attractive option for the treatment of renal stones because of its high stone-free rates (SFRs) and low morbidity.

OBJECTIVE

To describe our surgical technique for fURS, step-by-step, for the treatment of renal stones and to assess its effectiveness and safety.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective analysis of 316 consecutive patients who underwent fURS for renal stones at our institution between March 2014 and September 2015 was performed.

SURGICAL PROCEDURE

Ureteroscopy and laser lithotripsy using a standardized technique with last-generation flexible ureteroscopes.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Clinical data were collected in a dedicated database. Intraoperative and postoperative outcomes were assessed. A descriptive statistical analysis was performed.

RESULTS AND LIMITATIONS

The mean overall stone size was 16.5 ± 7.9mm. Ureteral access sheath placement was possible in 287 patients (90.8%). At 1-mo follow-up, the overall primary SFR was 79.1%; the secondary and tertiary SFRs were 89.5% and 91.5%, respectively. The mean operative time was 72.6 ± 27.5min. The mean number of procedures was 1.27. Complications were reported in 92 patients (29.1%) overall, with Clavien grade 1 in 55 patients (17.4%), grade 2 in 30 patients (9.5%), grade 3 in 6 patients (1.9%), grade 4 in 1 patient (0.3%), and grade 5 in none. The main limitation of the study was the retrospective nature.

CONCLUSIONS

The fURS procedure is safe and effective for the treatment of renal stones. A staged procedure is necessary to achieve stone-free status with large calculi.

PATIENT SUMMARY

Flexible ureteroscopy is an effective treatment with low complication rates for the majority of renal stones. Both the modern highly technological armamentarium and surgical know-how should be available.

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

OBJECTIVE

The aim of this study was to analyse prospective data on flexible ureteroscopy and laser fragmentation (FURSL) of large stones (> 2 cm) to assess whether a ureteral access sheath (UAS) is necessary for the treatment of large renal stones.

MATERIALS AND METHODS

Between March 2012 and October 2014, 43 patients with large stones underwent FURSL. Data were collected on a prospective database for patient demographics, stone characteristics and outcomes of FURSL with and without a UAS.

RESULTS

There were 27 men and 16 women with a mean age of 54 years (range 7-84 years). The cumulative stone diameter was 2.92 cm (range 2-5 cm), with an overall stone-free rate (SFR) of 83.7%. A total of 68 procedures was needed (average 1.58 procedures/patient). The overall complication rate was 8.8% (n = 6); these were Clavien class II complications associated with urinary tract infections treated with additional antibiotics. UAS was not used in 28 procedures (41.2%). Comparing outcomes in those who had a UAS versus those who did not, there were no statistical differences in SFR, complication rate or average number of procedures per patients.

CONCLUSION

Use of a UAS does not make any difference to the SFR or complication rate for FURSL in large stones (> 2 cm) and may not be routinely needed in all cases.

Safety and feasibility of day case ureteroscopy and laser lithotripsy (URSL) in patients with a solitary kidney

Introduction

The management of nephrolithiasis in patients with a solitary kidney poses a treatment challenge. The study aimed to evaluate the outcomes of ureteroscopy and laser stone fragmentation (URSL) for renal stones in these patients treated in our university teaching hospital.

Material and methods

Between July 2012 and December 2014, seventeen cases of URSL for stones in a solitary kidney were reviewed. Patient demographics, stone dimensions, perioperative and post-operative outcomes were recorded in a prospectively maintained database. Serum creatinine levels pre-procedure and at follow-up were also compared.

Results

Seventeen cases of URSL were conducted with a mean age of 52.9 ±19.9 years. 8 of the 17 (47%) patients had stones in multiple locations and 13 (76%) were in the lower pole. The mean ± SD stone size and BMI were 13.0 ±8.9 mm and 31.6 ±5.8 kg/m², respectively. The stone free rate (SFR) was 82.5%. Fourteen (82.5%) patients were discharged the same day and 16 cases (94%) were discharged within 24 hours. For patients with deranged pre-operative serum creatinine, the mean serum creatinine level improved from 131.2 ±68.3 µmol/L pre-URSL to 106.5 ±36.7 µmol/L at follow-up. There was one Clavien grade II complication with a patient requiring additional antibiotics for post-operative urinary tract infection. There were no other major or minor complications.

Conclusions

Day case ureteroscopy for stone disease in a solitary kidney is safe and feasible with a low complication rate and an overall improvement in renal function.