Parapelvic Renal Cyst Treatment with Flexible Ureteroscopy: Single Centre Experience.

BACKGROUND: This study aimed to assess the feasibility, safety, and efficacy of an endoscopic parapelvic renal cyst (PRC) incision using flexible ureterorenoscopy (fURS). MATERIAL AND METHODS: We retrospectively reviewed data concerning 16 patients in whom PRC incisions had been performed using fURS between January 2016 and January 2022. Two patients were excluded from the study owing to a lack of follow-up information. The cysts of all the patients were evaluated preoperatively by computed tomography. The patients' age, gender, cyst size, presenting symptoms, postoperative complications, and pre- and post-treatment visual analogue scale (VAS) scores were evaluated. Surgical success was defined as a reduction of more than half of the cyst size in the sixth postoperative month. RESULTS: A total of 14 patients were included in this study. The patients' mean age was 52.6 ± 8.8 years, and the mean cyst size was 69.1 ± 15.5 mm. Twelve (85.7%) patients presented with flank pain. Clavien-Dindo grade 1 complications were observed in two patients (14.3%), and grade 2 complications were observed in one (7.1%). The median VAS scores were significantly lower after treatment than before in patients who presented with flank pain (2 (1-2.8) vs 8 (7-8), respectively; p = 0.002). Surgical success rate was detected in 11 patients (78.6%) six months after the treatment. CONCLUSIONS: Endoscopic incision of the PRC is a feasible treatment modality with high success rates and low complication rates. However, multicentre studies with larger populations and longer follow-ups are needed to evaluate the lasting effects.

Propensity score matched analysis of treatment outcomes in pediatric ureteropelvic junction obstruction: a comparison between horseshoe and non-horseshoe kidneys.

BACKGROUND: Pediatric hydronephrosis poses distinct challenges, particularly in cases involving horseshoe kidneys (HSK). This retrospective study compares treatment outcomes between HSK and non-horseshoe kidneys (NHSK) in pediatric ureteropelvic junction obstruction (UPJO) patients. METHODS: A retrospective cohort study included 35 patients with HSK and 790 patients with NHSK undergoing pyeloplasty. Preoperative, intraoperative, and postoperative parameters were evaluated. Propensity score matching (PSM) balanced patient characteristics in the NHSK group. RESULTS: In comparison with NHSK, HSK exhibited a higher crossing vessel incidence (51.6% vs. 5.12%, P < 0.001) and smaller preoperative anteroposterior pelvic diameter (APD). Post 6 and 12 months, NHSK maintained a larger APD, with a higher P/C ratio at 12 months. PSM retained significantly higher crossing vessel incidence in HSK (51.6 vs. 3.61%, P < 0.001). Laparoscopic pyeloplasty (LP) in HSK showed lower postoperative length of stay (LOS). Postoperative ultrasound parameters favored NHSK. In HSK and NHSK with crossing vessels, HSK demonstrated higher complications even post-PSM (38.5% vs. 0%, P = 0.039). CONCLUSIONS: The study emphasizes the importance of recognizing crossing vessels in HSK-related hydronephrosis. Surgical success, although comparable between HSK and NHSK, requires tailored approaches. This investigation contributes valuable insights to pediatric urology, emphasizing personalized management for optimal outcomes.

Needle-perc-assisted endoscopic surgery versus retrograde intrarenal surgery for the treatment of 1- to 2-cm lower-pole renal stones in patients with unfavorable infundibulopelvic anatomy: a matched-pair analysis.

PURPOSE: To compare the safety and efficacy of needle-perc-assisted endoscopic surgery (NAES) and retrograde intrarenal surgery (RIRS) for the treatment of 1- to 2-cm lower-pole stones (LPS) in patients with complex infundibulopelvic anatomy. METHODS: Between June 2020 and July 2022, 32 patients with 1- to 2-cm LPS and unfavorable lower-pole anatomy for flexible ureteroscopy were treated with NAES. The outcomes of these patients were compared with patients who underwent RIRS using matched-pair analysis (1:1 scenario). The matching parameters such as age, gender, body mass index, stone size, hardness, and pelvicalyceal anatomy characteristics including infundibular pelvic angle, infundibular length, and width were recorded. Data were analyzed using the Student's t-test, Mann-Whitney U test, and Fisher's exact test. RESULTS: The two groups had similar baseline characteristics and lower-pole anatomy. The stone burden was comparable between both groups. NASE achieved a significantly better initial stone-free rate (SFR) than RIRS (87.5% vs 62.5%, p = 0.04). The auxiliary rates for the NAES and RIRS groups were 12.5% and 31.3%, respectively (p = 0.13). Finally, the SFR after 1 month follow-up period was still higher for the NAES group than RIRS group (93.8% versus 81.3%), but the difference was not statistically significant (p = 0.26). Concerning the operation duration, overall complication rates, and postoperative hospital stay, there were no differences between two groups. CONCLUSION: Compared to RIRS for treating 1- to 2-cm LPS in patients with unfavorable infundibulopelvic anatomy for flexible ureteroscopy, NAES was safe and effective with higher SFR and similar complication rate.

Utility of ultrasound-based scoring system in post-pyeloplasty recovery.

BACKGROUND/OBJECTIVE: Differentiation of uretero-pelvic junction obstruction (UPJO) from non-obstructive dilatation (NOD) is a major challenge. The aim of this retrospective study is to determine whether pyeloplasty prediction score (PPS) could predict the need for surgery and resolution after surgery. METHODS: Among patients with antenatally diagnosed hydronephrosis, those who were stable during post-natal follow-up were considered NOD. The UPJO group were the ones who worsened and underwent pyeloplasty based on conventional indications. All patients with UPJO underwent laparoscopic dismembered pyeloplasty. PPS was determined based on three ultrasound parameters obtained retrospectively: Society of Fetal Urology (SFU) grade of hydronephrosis, transverse anteroposterior (APD), and the absolute percentage difference of ipsilateral and contralateral renal lengths. RESULTS: Among 137 patients included (R:L = 59:73; M:F 102:35), 96 were conservatively managed (NOD), while 41 patients (29%) needed pyeloplasty (UPJO). Mean PPS was 4.2 (1.2) in the NOD group and it was significantly higher at 10.8 (1.63) in the UPJO group (p = 0.001). All patients with PPS > 8 needed a pyeloplasty, while two patients with PPS of 7 needed pyeloplasty due to drop in renal function. PPS cutoff value of >8 had a sensitivity 95%, specificity 100% and a likelihood ratio of 20. Post-pyeloplasty PPS resolution was proportional to the duration of follow-up. CONCLUSIONS: A PPS cutoff value of 8 or above is associated with the presence of significant UPJO. PPS is also useful in the assessment of hydronephrosis recovery post-pyeloplasty. The limitation of PPS: it can only be applied in the presence of contralateral normal kidney.

Fluid absorption during flexible ureteroscopy with intelligent control of renal pelvic pressure: a randomized controlled trial.

PURPOSE: To investigate fluid absorption and its influencing factors during flexible ureteroscopy with intelligent control of renal pelvic pressure (RPP). METHODS: A total of 80 patients with upper urinary tract calculi underwent flexible ureteroscopy with intelligent control of RPP by pressure-measuring ureteral access sheath and were randomly divided into four groups. The RPP of Groups A, B, and C were set at - 5, 0 and 5 mmHg, respectively. Conventional flexible ureteroscopy with uncontrolled pressure served as control Group D. The perfusion flow rate was set at 100 ml/min in the four groups, with 20 patients in each group. The fluid absorption was measured by 1% ethanol every 10 min. Operation time, stone-free rate, and complications were recorded. RESULT: Seventy-three patients were finally included in the RCT. The general and preoperative data of the patients were comparable between the groups. The fluid absorption of Groups A, B, and C was significantly less than that of Group D (P < 0.01). Fluid absorption and operation time were positively correlated, and the correlation coefficients R were 0.864, 0.896, 0.918, and 0.947, respectively (P < 0.01). The fluid absorption of patients with vomiting, fever and ureteral injury was greater than that of patients without complications in the four groups (P < 0.01). In different groups, fluid absorption was greater in patients with ureteral injury Post-Ureteroscopic Lesion Scale (PULS) 1-3 than in noninjured patients (P < 0.01). CONCLUSION: Flexible ureteroscopy with intelligent control of RPP effectively reduces the absorption of perfusion fluid. Operation time and ureteral injury are also key factors affecting perfusion fluid absorption. REGISTRATION NUMBER AND DATE: NCT05201599; August 11, 2021.

Robotic-assisted native pyeloureterostomy with indocyanine green, after kidney transplantation.

INTRODUCTION: Postoperative ureteral strictures and vesicoureteral reflux after ureteroneocystostomy for kidney transplant can be managed by endoscopic procedures like balloon dilation and endoscopic injections. Complicated/recurrent cases, however, are usually managed by reconstructive surgery. We hereby highlight our technique of robotic-assisted native pyeloureterostomy with indocyanine green (ICG). MATERIALS AND SURGICAL TECHNIQUE: A 57-year-old woman, diagnosed with grade 4 vesicoureteral reflux on her transplanted kidney, was considered a candidate for ureteral reimplantation. After an endoscopic part, where the ICG is inserted into the renal pelvis, we proceed with the robotic native pyeloureterostomy. The renal pelvis of the transplanted kidney was identified with the help of the ICG in firefly mode. After the dissection of the graft pelvis, we performed a tension-free pyeloureterostomy using the native ureter. The postoperative course was uneventful and the patient was discharged on the third postoperative day. DISCUSSION: Robotic-assisted pyelo-ureterostomy appears as a safe and efficient technique for management of complicated urological complications postrenal transplantation using the native ureter. Intrapelvic ICG injection, not possible with open surgery, helps identifying the grafted pelvis thus reducing operative time and avoiding unnecessary dissection of the vascular hilum of the graft. Because of minimal dissection and the short operative time, abdominal drainage is unnecessary and the postoperative course is usually uneventful with a fast discharge from the hospital.

Diagnosis and Management of Ureteropelvic Obstruction in Kidney Transplant Recipients and Outcomes of Foley Y-V Pyeloplasty.

OBJECTIVES: To evaluate the etiology and diagnostic tools for ureteropelvic obstruction in kidney transplant recipients, we investigated the short-term and long-term outcomes of Foley Y-V pyeloplasty. MATERIALS AND METHODS: We retrospectively reviewed 10 patients who underwent kidney transplant followed by additional interventions to treat obstructive ureteral pathologies between 2016 and 2020. We enrolled 4 patients who had received intervention to treat ureteropelvic obstruction. For these 4 patients, serum creatinine and estimated glomerular filtration rate levels were recorded at baseline, during the symptomatic period, and long-term. In this single center study, we investigated diagnostic tools and management strategies for ureteropelvic obstruction and assessed performance of Foley Y-V nondismembered pyeloplasty in kidney transplant recipients. RESULTS: Among 4 patients, graft function (assessed by serum creatinine and estimated glomerular filtration rate) worsened significantly (P = .03) in the symptomatic period of ureteropelvic obstruction in all patients; however, graft function levels improved rapidly to levels similar to baseline (P = .07) after Y-V pyeloplasty. In addition, no statistically significant difference was detected between baseline and longterm graft functions afterY-V pyeloplasty in follow-up (P = .28). CONCLUSIONS: Diagnosis and management of ureteropelvic obstruction in kidney transplant recipients are challenging due to rarity and lack of an ideal management algorithm.There is no specific diagnostic tool to discriminate this pathology from other ureteral pathologies; therefore, a regimen of conventional imaging modalities and diuretic renogram combined with endoscopic evaluation is more reliable. Moreover, nondismembered Foley Y-V pyeloplasty is effective and safe for graft function in the short-term and long-term.

New infundibulopelvic angle measurement method can predict stone-free rates following retrograde intrarenal surgery.

To enhance the accuracy of predicting stone-free rates after retrograde intrarenal surgery, we devised a novel approach to assess the renal infundibulopelvic angle. We conducted a retrospective review of patient records for those who underwent retrograde intrarenal surgery for renal stones between April 2018 and August 2019. Patient demographics, stone characteristics, and perioperative data were recorded. Subsequently, we introduced a modified angle measurement called the pelvic stone angle and evaluated its predictive performance for stone-free rates by comparing it with the traditional method in scoring systems. A total of 43 individuals were included in this study. Notable differences in stone burden and Hounsfield unit measurements were found between stone-free and non-stone-free patients. The pelvic stone angle demonstrated a good model fit when used in scoring systems, performing equally well as the conventional approach. The area under the receiver operating characteristic curve for the R.I.R.S. scoring system using the pelvic stone angle and the conventional approach did not show a significant difference. In conclusion, the predictive ability of the pelvic stone angle for stone-free rates was comparable to the old measurement method. Moreover, scoring systems using the pelvic stone angle exhibited a better model fit than those using the conventional approach.

Low anterolateral incision for single-port extraperitoneal robot-assisted pyeloplasty: description of technique and initial experience.

PURPOSE: This study aims to describe the surgical steps for the single-port low anterolateral extraperitoneal approach to pyeloplasty, report its feasibility, and share the initial outcomes of our experience. METHODS: We analyzed all consecutive patients who underwent single-port low anterolateral extraperitoneal pyeloplasty due to ureteropelvic junction obstruction (UPJO). The surgical steps included a pure single-port approach through a 3.5 cm low anterolateral incision two fingerbreadths above the superior pubic ramus. The ureter was localized and followed cranially, a dismembered pyeloplasty was performed, and a running ureteropelvic anastomosis was completed. No drains were placed. The urinary catheter was removed upon discharge, and the ureteral stent after 3-5 weeks. RESULTS: A total of eight cases (two adults and six children) were completed successfully, without complications or conversions. Median operative time, console time, and estimated blood loss were 208.5 min, 114.5 min, and 10.0 ml, respectively. All patients were discharged within 24 h, except for one that required urinary output observation due to retention. There were no major postoperative complications. The median pain score at discharge was 0/10. Only one patient was prescribed PRN opioids at discharge. The readmission rate was 0.0%. All patients were asymptomatic on their last follow-up with no definitive obstruction on imaging, and no requirement for additional procedures or stents. CONCLUSION: Single-port low anterolateral extraperitoneal pyeloplasty is a feasible alternative for surgical treatment of UPJO in adult and pediatric patients with improved recovery outcomes.

Effect of nephrostomy sheath size on renal pelvic pressure during endoscopic combined intrarenal surgery: artificial kidney model study.

BACKGROUND: This study aimed to evaluate the intrarenal pelvic pressure in endoscopic combined intrarenal surgery using an artificial kidney model. METHODS: An artificial kidney model was created using the Urovac evacuator™. Four sizes of nephrostomy sheaths (MIP-L: 25/26 Fr, MIP-M: 16.5/17.5 Fr, MIP-S: 11/12 Fr, MIP-XS: 8.5/9.5 Fr) and two sizes of ureteral access sheaths (12/14 Fr and 10/12 Fr) were installed into the model. For each combination of nephrostomy and ureteral access sheath, renal pelvic pressure was measured with and without insertion of the retrograde flexible ureteroscope. Irrigation from the nephroscope was adjusted to 40-160 mmHg using an automatic irrigation device, and the irrigation of the ureteroscope was by spontaneous dripping at 80 cmH2O. Conditions were measured six times, and the renal pelvic pressure was compared in different conditions. RESULTS: Without ureteroscope insertion through the ureteral access sheath, the renal pelvic pressure never exceeded 30 mmHg. Meanwhile, when the ureteroscope was inserted, the renal pelvic pressure increased as the nephrostomy sheath and ureteral access sheath became narrower and as the irrigation pressure increased. Intrarenal pelvic pressure exceeded 30 mmHg when the irrigation pressure was increased in 12/14 Fr ureteral access sheath when MIP-XS was used, and in 10/12 Fr ureteral access sheath when MIP-XS and MIP-S were used. CONCLUSIONS: The use of a thin nephrostomy sheath in endoscopic combined intrarenal surgery can lead to increased intrarenal pelvic pressure. Although our results are from an artificial kidney model, special care is suggested to be required when using a retrograde flexible ureteroscope simultaneously in treatment of patients.

Robotic pyeloplasty: Technological global panacea or geo-surgical nightmare?

To the Editor, Pelvi-ureteric junction obstruction (PUJO) is a well-recognised clinical entity characterised by functionally significant impairment of drainage of urine at the level of the pelvi-ureteric junction due to extrinsic or intrinsic obstruction and is encountered both by adult and paediatric urologists alike. Management of PUJO has been surgical historically, and the gold standard has been an open Anderson-Hynes dismembered pyeloplasty [...].

Retroperitoneoscopic Simple Nondismembered Pyeloplasty with Da Vinci Si Assistance to Prevent Alignment Shift.

Aims: Retroperitoneoscopic simple nondismembered pyeloplasty (SNDP) with da Vinci Si assistance was developed because of a possible risk for alignment shift after retroperitoneoscopic diamond-shaped bypass pyeloplasty (Diamond-Bypass; DP). Outcomes of SNDP and DP were compared. Materials and Methods: For SNDP, a small longitudinal incision is made on the border of the dilated pelvis and narrowed ureter at the ureteropelvic junction (UPJ). Extending this incision toward the pelvis allows identification of mucosa while maintaining the integrity of surrounding tissues that are so thin and fragile that they will not influence lumen alignment. Data for DP were obtained from a previously published article. Results: For SNDP (n = 3), mean age at surgery was 2.67 years (range: 1-4), mean operative time was 176 minutes. Mean postoperative Society of Fetal Urology (SFU) grades for hydronephrosis were 1.2, 0.7, and 0.6, 1, 2, and 3 months after stent removal, respectively. Postoperative diethylenetriaminepentaacetic acid (DTPA) was normal (n = 3). For DP (n = 5) mean age at surgery was 4.3 years (range: 1-14), mean operative time was 189 minutes. Mean postoperative SFU grades were 2.8, 2.2, and 1.6, respectively. Postoperative DTPA was normal (n = 4) and delayed (n = 1). All SNDP and DP were asymptomatic by 3 months after stent removal. Conclusion: Both SNDP and DP have favorable outcomes. If the UPJ is located at the lowest end of the renal pelvis, SNDP may improve hydronephrosis more quickly.

Feasibility and Effectiveness of Repeat Laparoscopic Pyeloplasty for Recurrent Ureteropelvic Junction Obstruction in Pediatric Patients.

Objective: To assess the outcomes of redo laparoscopic pyeloplasty (RLP) in pediatric patients with recurrent ureteropelvic junction obstruction (UPJO) in contrast to redo open pyeloplasty (ROP). In addition, evaluate the feasibility and efficacy of RLP as a treatment modality for recurrent UPJO in children. Materials and Methods: The data of 44 patients from March 2012 to March 2022, who underwent redo pyeloplasty, were retrospectively reviewed. In Group RLP, the children underwent RLP, whereas ROP was attempted in Group ROP. Demographics, clinical manifestations, surgical duration, hospitalization duration, complication rates, and treatment success were examined within the respective groups. Moreover, preoperative and postoperative measurements of anterior-posterior diameter of the renal pelvis (APD), preoperative assessment of differential renal function (DRF), and the percentage of improvement in DRF (PI-DRF) were subject to analysis. Results: The study included 28 patients who underwent RLP (Group RLP), and 16 patients who underwent ROP (Group ROP). In all cases, the Anderson-Hynes technique was employed. There was no significant difference between the two groups regarding age, body mass index, gender distribution, affected side, preoperative APD, postoperative APD, and preoperative DRF. In comparison to Group ROP, Group RLP exhibited a shorter hospitalization duration, a longer surgical procedure duration, and a higher percentage improvement in PI-DRF. The median follow-up period for Group RLP was 25 months, whereas it was 25.5 months for Group ROP. Notably, the success rates were similar between the two groups, with a success rate of 89.2% in RLP and 87.5% in ROP (p = 0.634). Conclusion: RLP has a comparable success rate to ROP and is a safe, effective, and feasible procedure for the treatment of failed pyeloplasty in children.

Treatment of ureteropelvic junction obstruction in patients with renal calculi via laparoscopic pyeloplasty and flexible vacuum-assisted ureteral access sheath ureteroscopy: a multicenter retrospective observational study.

BACKGROUND: Ureteropelvic junction obstruction (UPJO) is a common obstructive disease of the urinary tract. UPJO patients commonly exhibit coexistent renal calculi. The main aim of therapy is to relieve the obstruction and remove the stones at the same time. METHODS: This retrospective study included 110 patients diagnosed with UPJO coexisting with multiple renal calculi at Shanxi Bethune Hospital and the First Hospital of Shanxi Medical University between March 2016 and January 2022. Patients were divided according to the methods used for dealing with UPJO and renal calculi. In Group A, patients underwent traditional open pyeloplasty and pyelolithotomy. In Group B, patients underwent percutaneous nephrolithotomy first and then laparoscopic pyeloplasty. In Group C, patients underwent flexible cystoscopy to remove stones and then laparoscopic pyeloplasty. In Group D, patients underwent flexible vacuum-assisted ureteral access sheath (FV-UAS)assisted flexible ureteroscopy (f-URS) and underwent laparoscopic pyeloplasty. The stones were broken up using a holmium laser. The pyeloplasty success rate, stone clearance rate, operation time, bleeding amount, complication occurrence rate, postsurgical pain, length of stay, and hospitalization cost were compared between the groups. The follow-up period was at least 2 years. RESULTS: The use of f-URS and the FV-UAS, significantly increased the renal stone clearance rate and significantly reduced the complication incidence and operation time in UPJO patients with multiple coexisting renal calculi. CONCLUSIONS: Laparoscopic pyeloplasty combined with f-URS and FV-UAS is safe and effective for treating UPJO in patients complicated by renal caliceal stones. TRIAL REGISTRATION: Retrospectively registered.

Single port robot-assisted pyeloplasty: An early comparative outcomes analysis.

BACKGROUND: The treatment paradigm for ureteropelvic junction obstruction (UPJO) has shifted towards minimally invasive pyeloplasty. A comparison Single Port (SP) and Multi Port (MP) robot-assisted pyeloplasty (RAP) was performed. METHODS: Data from consecutive patients undergoing SP RAP or MP RAP between January 2021 and September 2023 were collected and analysed. Co-primary outcomes were length of stay (LOS), Defense and Veterans Pain Rating Scale (DVPRS), and narcotic dose. The choice of the robotic system depended on the surgeon's preference and availability of a specific robotic platform. RESULTS: A total of 10 SP RAPs and 12 MP RAPs were identified. SP RAP patients were significantly younger [23 years (20-34)] than MP RAP [42 years (35.5-47.5), p < 0.01]. No difference in terms of OT (p = 0.6), LOS (p = 0.1), DVPRS (p = 0.2) and narcotic dose (p = 0.1) between the two groups was observed. CONCLUSIONS: SP RAP can be implemented without compromising surgical outcomes and potentially offering some clinical advantages.

Pediatric Robot-Assisted Laparoscopic Pyeloplasty: Where Are We Now?

PURPOSE OF REVIEW: This review aims to provide an in-depth exploration of the recent advancements in robot-assisted laparoscopic pyeloplasty (RALP) and its evolving landscape in the context of infant pyeloplasty, complex genitourinary (GU) anatomy, recurrent ureteropelvic junction (UPJ) obstruction, cost considerations, and the learning curve. RECENT FINDINGS: Recent literature highlights the safety and efficacy of RALP in treating the infant population, patients with complex GU anomalies, and recurrent UPJO which were all traditionally managed using the open approach. Cost considerations are evolving, with the potential for RALP to have a lesser financial burden. In addition, the learning curve for RALP is diminishing due to robust training programs and advances in research. RALP has become the gold standard in the treatment of UPJO in pediatric urology at many children's hospitals. Surgeon comfort and research in this space allow safe and successful reconstruction in the most challenging of cases.

The learning curve of robot-assisted laparoscopic pyeloplasty in children.

To explore the learning curve of robot-assisted laparoscopic pyeloplasty (RALP) in children. The clinical data, surgical information, and postoperative complications of consecutive cases of RALP performed by the same surgeon in Shanghai Children's Hospital from January 2014 to July 2020 were retrospectively analyzed; the surgeon is a senior pediatric urologists who is proficient in laparoscopic pyeloplasty; the data consist of console time (CT), suture method when anastomosing ureteropelvic junction (UPJ), number of stitches (N), anastomosis time per stitch (tn), the average suture time per stitch (T) = (suture time of first stitch (t1) + second stitch (t2) + … + tn)/N, postoperative complications, and surgical outcome. The learning curve was depicted by cumulative sum method (CUSUM) and validated by cumulative method (CUM). Of the 88 cases, 64 cases were included in present study. Median CT was 104 (83-117) min, mean T was 109 ± 17 s. There were ten cases of Clavien-Dindo Grade I complication and two cases of Clavien-Dindo Grade IIIb complication. The median follow-up time was 237 (87-627) days. The learning curve of CT has three stages, with inflection points at 11th and 57th case, and T has two stages, with inflection points at 19th case. There was a statistically significant difference between the console time and length of stay on both sides of the inflection point (P < 0.05), but there was no statistically significant difference in age, gender, etiology, clinical manifestation, surgical outcome, and complication (P > 0.05). For a senior pediatric urologists who is proficient in laparoscopic pyeloplasty, the learning curve of RALP can be divided into three stages, preliminary exploration stage, mastery stage, and proficiency stage. It takes about 11 cases to achieve the mastery stage, and it takes about 57 cases to achieve the proficiency stage. The learning curve focused on the suture technique of the surgeon is divided into two stages, and after a learning period of 19 cases, it will reach the proficiency stage of suturing UPJ.

Response to "Outcomes of infants undergoing laparoscopic pyeloplasty: A single-center experience".

Although studies such as that of Erol et al. can raise doubts to a pediatric urologist about whether or not to carry out a laparoscopic approach in a pyeloplasty in infants, especially due to the percentage of complications, meta-analyses such as the one mentioned reinforce the safety and good results of the laparoscopic approach in these patients. The laparoscopic approach provides potential benefits over open surgery, such as better visualization of polar vessels, less aggressive dissection of periureteral tissues, or smaller scars. Although many open pyeloplasty incisions can be made small, they will never be smaller than those with 3 or 5 mm ports. Thus, any urologist or pediatric surgeon with experience in laparoscopic surgery has sufficient data at their disposal to be confident in the reproducibility and safety of laparoscopic surgery for pyeloplasties in infants. It is appreciated that works such as that of Erol et al. help minimally invasive techniques expand within pediatric urology.

Robotic-Assisted Laparoscopic Pyeloplasty in Challenging Cases of Ureteropelvic Junction Obstruction in the Pediatric Population: A Multicenter Review.

Purpose: To report a multi-institutional international experience in performing robotic pyeloplasty for complicated cases of ureteropelvic junction obstruction (UPJO) in the pediatric population and assess feasibility and outcomes. Materials and Methods: Retrospective chart review of all pediatric patients who underwent robotic-assisted laparoscopic pyeloplasty (RALP) for UPJO in challenging cases between 2013 and 2021 was included. Demographics, perioperative surgical data, complications, and results are described. Challenging cases were defined as bilateral UPJO, failure of previous open pyeloplasty (thus re-do cases), correction of UPJO in kidneys with anatomical variations, huge hydronephrosis, and low-weight infants (<6 kg). Results: Over an 8-year period, 36 children (62% males and 38% females) met the inclusion criteria for our study. Fifteen patients underwent RALP for recurrent UPJO; among them, 2 children required simultaneous surgery for renal stones, 3 cases of lower pole UPJO in double collecting system, 3 cases of pelvic and horseshoe kidneys, 10 cases of infants weighing <6 kg, 3 cases of huge hydronephrosis, and 2 cases of bilateral UPJO. The median age and weight were 36 months (interquartile range [IQR] 14-84) and 12 kg (IQR 10-20.5), respectively. All robotic cases were completed successfully with no conversion to an open procedure. The median operative time was 120 minutes (IQR 90-135). The mean length of hospital stay was 2.6 days. Four patients (17%) had postoperative complications-1 ileus (Clavien-Dindo grade [CDG] I) and 3 urinary tract infections (CDG II). No CDG III or higher complication was encountered. At a median follow-up of 36 months, the success rate was 95% with 1 patient requiring another re-do procedure due to recurrent obstruction. Conclusions: Our data suggest that RALP is safe and effective even for challenging cases of UPJO in children.