Retrograde intrarenal surgery using ureteral access sheaths is a safe and effective treatment for renal stones in children weighing <20 kg

Safety and feasability of ureteroscopy for pediatric stone, in children under 5 Years (SFUPA 5): A French multicentric study

INTRODUCTION

Ureteroscopy (URS) can be proposed as first-line therapy for the management of pelvic stones from 10 to 20 mm and for lower ureteric stones in children. However, little is known about the success and the morbidity of URS in young children. Ureteroscopic treatment may present matters in young children because of the small size of the pediatric kidney and the small size of the collecting system.

OBJECTIVE

To assess safety and efficacy of URS for the treatment of urinary stones in children aged of 5 years or less.

STUDY DESIGN

After the institutional ethical board approval was obtained, we conducted a retrospective, analytic, multicentric study that included all URS performed between January 2016 and April 2022 in children aged of 5 years or less. In this non-comparative case series, anonymized pooled data were collected from 7 tertiary care centers of pediatric patients. Endpoints were the one-session SFR at 3 months and per and postoperatives complications. Descriptive statistics were applied to describe the cohort.

RESULTS

Eighty-three patients were included. For them, 96 procedures were performed at the median age of 3.5 years (IQR: 0.8-5) and median weight of 14 Kg (6.3-23). Median stone size was 13 mm (4-45). There were 65 (67 %) renal stones treated with flexible URS, most of which were in the renal pelvis (30 %) and in the lower calix (33 %). A ureteral access sheath was used in 91 % procedures. Preoperative ureteral stent was placed in 52 (54 %) of patients. None of patients had ureteral dilatation. The single-session SFR was 67.4 % (56.3 and 89.2 % for flexible URS and semi-rigid URS respectively) and children require 1.4 procedures to achieve complete stone clearance. The overall complication rate was 18.7 %, most of them were minor (Clavien I-II). Intraoperative perirenal extravasation (Clavien IIIb) due to forniceal rupture was documented in 6.2 % of cases, related to an increased intrapelvic pressure (IPP) performed in a closed pelvicalyceal system.

DISCUSSION

Pediatric urologists should be aware of forniceal rupture based on the presence of extravasation of contrast during endourological procedures especially when they have difficulties to reach lower caliceal stone in small patient.

CONCLUSION

URS in patients aged of 5 years or less, is a complex minimally invasive procedure with reasonable efficacy and low morbidity. Intrarenal stones treated by RIRS in young children carries the risk of additional procedures to complete stone clearance.

Retrograde Intrarenal Surgery for Renal Stones: Is It a Safe and Effective Option in Preschool Children?

INTRODUCTION

Few studies in the literature describe the Retrograde Intra-Renal Surgery (RIRS) outcome in preschool children. We evaluated the feasibility, stone-free rate and complications of RIRS in preschool children at two European tertiary care centres of Pediatric Urology.

MATERIAL AND METHODS

The retrospective study includes all children undergone RIRS for stones <25 mm from 2017 to 2022. Patients were divided into Group 1 <5 years (G1) and Group 2 >5 years (G2). Semirigid ureterorenoscope 4.5-6.5 Ch and a 7.5 Fr flexible ureteroscope with a 9.5/11 Ch ureteral access sheath (UAS) were used. Stone-free rate (SFR) was evaluated at 3 months. Fischer/Chi-square test for qualitative data and Mann-Whitney for quantitative data were used for statistical analysis.

RESULTS

63 patients underwent RIRS, 19 G1-patients, median age 3.55 ± 1.06 years (range 1.5-5 years), and 44 G2-patients, median age 11.25 ± 2.95 (range 6-17 years) (p < 0.00001). Intraoperative complications occurred in 1 case in G1(5%) and 3 in G2(7%) (p = 1): two minor ureteric injuries in G2 were treated by a prolonged JJ-stent. Postoperative fever was reported in 3 cases in G1 (16%) and 4 in G2(9%) (p = 0.42), while post-operative hematuria in 4 G1-patients (21%) and in 7 G2-patients (16%) (p = 0.72). SFR was 84.2% in G1 and 88.6% in G2. At an average follow-up of 15.05 ± 4.83 months in G1 and 19.95 ± 10.36 months in G2, reintervention for residual stones was necessary in 3 cases in G1(16%) and in 6 cases in G2(14%) (p = 1).

CONCLUSIONS

In a European country with low-volume pediatric stone centers, RIRS is a promising therapeutic option in young children as it offers acceptable stone-free rate and a low incidence of high-grade complications.

LEVEL OF EVIDENCE

III.

Role of Preoperative Ureteral Stent on Outcomes of Retrograde Intra-Renal Surgery (RIRS) in Children. Results From a Comparative, Large, Multicenter Series

OBJECTIVE

To assess outcomes of pre-stenting versus non-pre-stenting in children undergoing retrograde intrarenal surgery (RIRS) for intrarenal stones.

METHODS

Children/adolescent with kidney stones undergoing RIRS in 9 centers between 2015 and 2020 were retrospectively reviewed.

EXCLUSION CRITERIA

ureteral lithotripsy, bilateral procedures. Stone-free status was evaluated at 3-month and defined as a single residual fragment (RF) ≤2 mm/absence of multiple fragments. Patients were divided into two groups (Group 1 no-prestenting; Group 2 prestenting). Student's, Chi-square and Fisher's exact test was used to assess difference between groups. Univariable and multivariable logistic regression analysis were performed to predict RF. Statistical significance: P-value <0.05.

RESULTS

Three hundred eighty-nine children/adolescents were included (192 patients in Group 1). Prestented patients were younger compared with non-prestented (mean age 8.30 ± 4.93 vs 10.43 ± 4.30 years, P < 0.001). There were no differences in stone characteristics (number, size, locations). Lasing and total surgical time were similar. Urinary tract infections were more prevalent in Group 2 (10.7%) compared to Group 1 (3.7%, P = 0.016). Sepsis occurred in 2.1% of patients in Group 2 and no patient in Group 1 (P = 0.146). 30.7% patients in Group 1 and 26.4% in Group 2 had RF (P = 0.322). In univariate logistic regression analysis, stone size was associated with RF (OR 1.12 95%CI 1.06-1.18, P < 0.001), whereas Thulium fiber laser with a lower incidence (OR 0.24 95%CI 0.06-0.69, p=0.020). Multivariate logistic regression analysis showed that stone size was associated with RF (OR 1.20 95%CI 1.08-1.36, P = 0.001).

CONCLUSIONS

RIRS showed similar stone-free rate in pre and non-prestented children/adolescents, although prestented patients were younger. A higher risk of post-operative infections was reported in prestented patients.

What is the best approach for pediatric kidney stones of moderate-sized between shock wave lithotripsy, ultramini percutaneous nephrolithotomy and retrograde intrarenal surgery?

PURPOSE

This study aimed to compare the results of ultramini percutaneous nephrolithotomy (UMP), shock wave lithotripsy (SWL) and retrograde intrarenal surgery (RIRS) in pediatric patients with kidney stones 10-20 mm size.

METHODS

The files of 159 pediatric patients (36 RIRS, 39 SWL, 84 UMP) with kidney stones were reviewed retrospectively. Preoperative age, sex, stone size and location were evaluated. The three methods were compared in terms of operation and fluoroscopy duration, complications with the modified Clavien grading system, and stone-free rate (SFR) in the postoperative first month.

RESULTS

The stone burdens of the groups were similar (P = 0.102). At the end of the first month, SFR was higher in the RIRS and UMP groups compared to the SWL group (88.9%, 92.9% and 69.2%, respectively, P = 0.002). UMP had higher SFR for lower pole stones than the other two methods (P = 0.042). There was no difference in complications between the three methods (P = 0.758).

CONCLUSION

SFR was similar for all three methods in all localizations, apart from lower pole stones. UMP had higher SFR for lower pole stones than the other two methods. There was no difference in terms of complications between the three methods.

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

Context

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

Objective

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

Evidence acquisition

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

Evidence synthesis

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

Conclusions

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

Patient summary

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

Paediatric stone management: innovations and standards

PURPOSE OF REVIEW

The aim of this study was to discuss current trends and recent developments in the surgical management of paediatric urolithiasis.

RECENT FINDINGS

Medical expulsive therapy (MET) is considered as an option for the treatment of children with ureter stones. Extracorporeal shockwave lithotripsy (SWL) remains as a first option for majority of kidney stones and upper ureter stones. Advances in endourology have led to increased adoption of retrograde intrarenal surgeries (RIRS) and percutaneous nephrolithotomy (PCNL/mini-PCNL/ultra-mini-PCNL/micro-PCNL).

SUMMARY

Management of paediatric stone disease has developed significantly in the past decade. However, the evidence in the literature remains disproportional to these advances. Well designed multicentric studies are still needed to compare effectiveness and safety of these procedures.

Retrograde Intrarenal Surgery (RIRS) for upper urinary tract stones in children below 12 years of age: A single centre experience

OBJECTIVE

Retrograde Intra Renal Surgery (RIRS) is a minimally invasive surgical modality for the treatment of renal stones. We evaluated the efficacy of RIRS in children below aged 12 years of age in the form of stone-free rate (SFR), complications and the feasibility of the procedure.

MATERIALS AND METHODS

This retrospective study included all children ≤ 12 years of age, with upper urinary tract stones single or multiple ≤ 15 mm in size who underwent RIRS between February 2019 to November 2021. RIRS was performed with 7.5 Fr flexible ureterorenoscope over the guidewire, the stones were dusted with Laser and the ureteral stent was left after RIRS. All patients had the post-procedure stent removed within 3 weeks after checking for residual stones with X-ray and ultrasonography of Kidney-Ureter-Bladder (USG-KUB). Follow-up USG KUB was done at 4 months.

RESULTS

15 patients included in our study met the inclusion criteria. The mean age was 8.7 ± 2.8 years, the mean stone size was 11.26 ± 2.14 mm and 26.6 % had multiple stones. Retrograde access failure was noted in 36.3 % in non stented patients. The mean operative time was 72.6 ± 20 minutes, fluoroscopy time was 4.4 ± 0.9 minutes and the mean LASER time was 26 ± 3.9 minutes. The mean hospital stay was 2.8 ± 0.9 days. Ureteral access sheath (UAS) was used in one patient. Conversion to mini PCNL was done in one pre stented patient due to access failure and one patient had a second look RIRS for residual stone. No major complications were noted except onr patient who had sepsis. The stone-free rates were 93.3% after primary RIRS and 100% after second look RIRS.

CONCLUSIONS

RIRS is a feasible, safe procedure for pediatric upper urinary stones with excellent stone-free rates and a low rate of complications.

Does ureteral access sheath have an impact on ureteral injury?

Objective:

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

Materials and Methods:

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

Results:

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

Conclusion:

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

Factors associated with the stone-free status after retrograde intrarenal surgery in children

INTRODUCTION

Paediatric urolithiasis has a recurrent nature because it is frequently associated with metabolic or anatomical disorders or infectious conditions. The rising incidence of the disease with its recurrent nature emphasises the need for minimally invasive therapeutic options. In this study, we aimed to evaluate efficacy and factors affecting the success of retrograde intrarenal surgery (RIRS) in children.

MATERIALS AND METHODS

Patients who underwent RIRS were evaluated retrospectively. Two different flexible ureteroscopes (F-URS) were used (7.5F F-URS and 7.95F with a 4.9F bullet-shaped tip). Irrespective of size, all residual fragments were considered as failure. Age, stone size, stone localisation, Hounsfield Unit (HU), stone-free rate (SFR) and complications were evaluated.

RESULTS

Forty-six patients (29 boys and 17 girls) with a median age of 70.5 months (6-214 months) were treated with RIRS between August 2014 and November 2019. The median operative time was 60 minutes (45-120 minutes). The median follow-up was 26 months (3-65 months). Fourteen patients had lower pole and 10 patients had multiple stones. Ureteral access sheath (UAS) was used in 16 (35%) patients. SFR was 61%. The median number of general anaesthesia was 2 (min 1, max 5). Auxiliary semirigid URS, PCNL and repeat RIRS were required in 4, 6 and 5 patients, respectively. Two patients had postoperative febrile urinary tract infection (UTI) as a complication. Age was associated with post-operative febrile UTI. Presence of stones with HU lower than 700, being operated 4.9F F-URS and without UAS were associated with better SFR.

CONCLUSIONS

RIRS is a minimally invasive method with low complication rates in the treatment of childhood stone disease. Higher stone-free rates are obtained in low HU stones and cases in which we used 4.9 F tip F-URS.

Safety and Outcomes of using ureteric access sheath (UAS) for treatment of Pediatric renal stones: Outcomes from 2 tertiary endourology centers

OBJECTIVE

To look at the safety and outcomes of using ureteral access sheath (UAS) for pediatric renal stones. The use of UAS is variable in urological practice with very little clinical work on their use in pediatric kidney stone disease.

PATIENTS AND METHODS

Data was retrospectively collected from 2 large European tertiary endourology centers for all pediatric patients (≤16 years) with renal stones who underwent flexible ureteroscopy and lasertripsy (FURSL) via UAS. Data was collected on patient details, stone demographics and clinical outcomes of the FURSL procedure.

RESULTS

Forty-eight patients with a mean age of 10.7 years were treated with FURSL for a mean single and cumulative stone size of 10.4 mm and 15 mm respectively, with two-third having multiple stones and stones in the lower pole. The initial and final stone free rate (SFR) was 66.7% and 100% respectively with 1.3 procedures/patient. One patient each had intra-operative grade 1 ureteric injury and post-operative UTI, with no other injuries or complications noted. Over a mean follow-up of 17 months, no other complications were noted.

CONCLUSION

Ureteral access sheath is safe for treatment of pediatric renal stones with excellent outcomes and are especially useful for larger or multiple stones. While there does not seem to be any medium-term sequalae, to avoid risk of ureteral injury, we would suggest using the smallest size sheath possible. We would argue these procedures are best done in specialist high-volume endourology units for optimal results.

External Validation of Two Predictive Models for Postoperative Fever After Retrograde Intrarenal Surgery in Pediatric Patients

Objective: The aim of this study is to validate the efficacy and reliability of two predictive models for postoperative fever after retrograde intrarenal surgery (RIRS) in pediatric patients Materials and Methods: A total of 124 children who were treated with RIRS between August 2014 and August 2020 in our center were included. All the predictors were obtained by preoperative routine examinations. Receiver operative curve (ROC) and area under curve (AUC) were showed to compare the predictive power of the two models. Results: One hundred twenty-four children included of 94 boys and 30 girls, with median ages of 2.1 (1.3, 7.0) years and median body mass index of 17.3 (15.6, 20.6) kg/m². The total points of the two nomograms were 81.0 (67.3, 90.3) and 45.5 (20.4, 94.0). Eventually, 21 children (16.9%) suffered from postoperative fever. With the exception of C-reactive protein values (25.0 mg/L vs 5.0 mg/L, p = 0.015), irrigation volumes (800 mL vs 500 mL, p = 0.01), and total points of the two predictive models (Nomogram 1: 88.0 vs 76.0, p < 0.001; Nomogram 2: 76.0 vs 39.0, p = 0.016), there was no statistical difference detected between the fever and nonfever groups. ROCs showed that Nomogram 1 presented with better predictive accuracy and efficacy with excellent AUC values of 0.805 in comparison with Nomogram 2 (0.805 vs 0.664, p = 0.025). Conclusion: We reported a sample of 124 children undergoing RIRS with a final stone-free rate of 87.1%. Twenty-one pediatric patients (16.9%) suffered from postoperative fever. Nomogram 1 presented with better predictive power for postoperative fever after RIRS in pediatric patients.

The optimal settings of holmium YAG laser in treatment of pediatric urolithiasis

The aim of this study is to present our experience on the use of the holmium:yttrium-aluminum-garnet (Ho:YAG) laser in pediatric patients for pediatric urolithiasis and describe the optimal settings. A total of 116 children who underwent urolithiasis treatment (percutaneous nephrolithotomy (PNL), ureterorenoscopy (URS), retrograde intrarenal surgery (RIRS)) were included. The mean age of the patients was 8.4 ± 5.2 years (1-18). The mean follow-up was 26 ± 8.8 months (9-45). There was no difference between the mean stone sizes of PNL and RIRS patients (p = 0.816). Operations were performed with 200, 272, and 365-μm fibers. In mini-URS, stone fragmentation was achieved with the energy settings set between 0.5 and 1 J and frequency set to > 8 Hz. In RIRS, fragmentation was achieved with the setting of 0.5-0.8 J at 10-20 Hz. Stone fragmentation was performed with energy settings of 0.8 to 2 J between 5 and 15 Hz for PNL. There was no significant difference between the stone-free rates of the PNL and RIRS (p = 0.150). Four postoperative complications occurred (Clavien II), which included febrile urinary infections in two patients who underwent mini-URS, one patient who underwent PNL, and one patient who underwent RIRS. Our results confirmed that Ho-YAG laser can be effectively used in children for stone treatment by using low-energy high-frequency settings for URS and RIRS and a high energy setting for PNL.

Retrograde intrarenal surgery for renal stones in children <5 years of age

Introduction

There are very few studies in the literature describing retrograde intrarenal surgery (RIRS) in preschool children. We have evaluated the feasibility, stone-free rate, and complications of RIRS in children <5 years of age.

Methods

All children <5 years of age and stone size <2 cm (renal/proximal ureteric), who underwent RIRS at our hospital from February 2010 to May 2020 were included in this retrospective study. All children were prestented for the passive dilatation of ureter. A 7.5 Fr flexible ureterorenoscope was introduced over the ureteral access sheath (UAS) or over a guidewire. At 2 weeks, the stent was removed and at 2 months the child was evaluated for residual stones.

Results

A total of 62 children with 67 renal units met the inclusion criteria. The mean age was 42.11 months (4-60 months). Mean weight was 13.31 kg (6-16.3 kg). Mean stone size was 11.9 mm (7.3-18.2 mm). Majority of the stones were in pelvis (37.8%). UAS 9.5/11.5 Fr was placed in 40 (63.5%) children. Mean operative time was 55.2 min; mean hospitalization was 61 h. Four out of the 67 renal units (5.9%) required conversion to minipercutaneous nephrolithotomy in the same sitting, due to access failure. Two cases who developed post-operative fever required a change of antibiotics. Two cases required ureteroscopy for steinstrasse postoperatively. Stone-free rate at 2 months for stones size ≤2 mm was 76.3%.

Conclusion

Pediatric RIRS is a promising option in young children as it offers acceptable stone-free rates and a low incidence of high-grade complications. However, it requires expertise and should be offered in tertiary care centres.

Influence of Body Mass Index on the Surgical Outcomes of Flexible Ureteroscopy for Pediatric Upper Urinary Tract Aalculi-A Single Surgeon Experience

OBJECTIVE

To examine the association between body mass index (BMI) and surgical outcomes of flexible ureteroscopy (FURS) for pediatric upper urinary tract calculi and to estimate the influence of BMI percentile on the learning curve of pediatric FURS.

MATERIALS AND METHODS

We reviewed our prospectively maintained database containing children who had kidney or ureteral stones from June 2014 to April 2019. We calculated BMI and plotted it on the Centers for Disease Control and Prevention growth chart for sex and age to estimate BMI percentile. Patient demographics, intraoperative data, stone characteristics, stone-free rate (SFR), and complication rate (CR) were analyzed. Learning curves stratified by BMI percentile groups were generated.

RESULTS

The final analysis included 161 children, of whom 63 (39.1%) had upper body weight percentile (UBW), 64 (39.8%) had normal body weight percentile (NBW), and 34 (21.1%) had lower body weight percentile (LBW). The median stone burden of the 3 groups were 1.14 (IQR 0.50-3.41), 1.13 (IQR 0.70-3.14), and 0.95 (IQR 0.50-1.77), respectively (P = .17). The SFRs were 90.5% (57/63) in the UBW group, 81.2% (52/64) in the NBW group and 70.6% (24/34) in the LBW group (P = .04). The CRs were 15.9% (10/63), 21.9% (14/64), and 29.4% (10/34), respectively (P = .29). The learning curves showed that the SFR of FURS could be improved after about 100 cases. And decreasing BMI could steepen the learning curve of SFR.

CONCLUSIONS

BMI is associated with the SFR of FURS. LBW children had the lowest SFR compared to UBW and NBW children. Lower BMI percentile makes the success of FURS more challenging.

Semi-closed-circuit vacuum-assisted mini percutaneous nephrolithotomy in the pediatric population: the initial experience of two tertiary referral centers

BACKGROUND

Percutaneous nephrolithotomy (PCNL) is the gold-standard for complex renal stones treatment in the pediatric population. While the miniaturization of PCNL reduces the risk of bleeding, it can hinder surgical and functional outcomes. The aim of the study was to assess the safety and feasibility of semi-closed-circuit vacuum-assisted Mini-PCNL (vmPCNL) in pediatric patients.

METHODS

From January 2017 to December 2018, we prospectively collected data on consecutive vmPCNLs from two European tertiary referral centers. The procedure was performed with the ClearPetra^® (Well Lead Medical Co., Ltd., Guangzhou, China) access sheath equipped with a lateral arm connected to the aspiration system (pressure setting ~120-150 cmH<inf>2</inf>O) by a 200 Ml plastic stone collector. Pre-, intra- and postoperative data and costs were analyzed. The stone-free rate (SFR) was defined as absence of residual fragments >4 mm with either ultrasound or kidney, ureter, and bladder X-ray.

RESULTS

Eighteen vmPCNLs were performed in 16 renal units of 13 children. The median age was 119 months (IQR: 97-160) and the weight was 29 Kg (IQR: 25-40). The median cumulative stone size was 32 mm (22-46) with 8 (44.4%) cases of staghorn stones. The OT was 128 min (IQR: 99-167). The basketing was unnecessary in 6/18 (33%) cases. Neither intra-operative complications nor blood transfusions occurred. Postoperative fever was observed in 5/18 (27.8%) cases; in one case a double J ureteral stent was placed for concomitant hydronephrosis. The SFR was 81.3% (13/16), rising to 93.8% (15/16) after ancillary procedures. The materials costs of a vmPCNL (734.8 €) were comparable to mini-PCNL using a reusable set (710.7 €).

CONCLUSIONS

The vmPCNL seems to be sustainable, safe and feasible for kidney stones treatment in the pediatric population.

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.