Risk and protective factors for secondary procedures after endoscopic dilatation of primary obstructive megaureters.

PURPOSE: High-pressure balloon dilatation (HPBD) of the ureterovesical junction with double-J stenting is a minimally invasive alternative to ureteral reimplantation or cutaneous ureterostomy for first-line surgical treatment of primary obstructive megaureter (POM). The aim of our study was to identify the risk factors associated with the need for secondary procedures due to HPBD failure. METHODS: Prospective data were collected from patients who underwent HPBD for POM between 2007 and 2021 at a single institution. The collected data included patient demographics, diagnostic modalities, surgical details, results, and follow-up. Multivariate logistic regression analysis was performed. RESULTS: Fifty-five ureters underwent HPBD for POM in 50 children, with a median age of 6.4 months (IQR: 4.5-13.8). Nineteen patients (37.25%) underwent secondary ureteric reimplantation, with a median of 9.8 months after primary HBPD (95% CI 6.2-9.9). The median follow-up was 29.4 months (IQR: 17.4-71). Independent risk factors for redo-surgery in a multivariate logistic regression model were: progressive ureterohydronephrosis (OR = 7.8; 95% CI 0.77-78.6) and early removal of the double-J stent. A risk reduction of 7% (95% CI 2.2%-11.4%) was observed per extra-day of catheter maintenance. The optimal cut-off point is 55 days, ROC curve area: 0.77 (95% CI 0.62-0.92). Gender, distal ureteral diameter, pelvis diameter, dilatation balloon diameter and preoperative differential renal function did not affect the need for reimplantation. CONCLUSIONS: The use of a double-J stent for at least 55 days seems to avoid the need for a secondary procedure. Therefore, we recommend removing the double-J catheter at least 2 months after the HBPD.

Advancements in Surgical Management of Megaureters.

PURPOSE OF REVIEW: To review and describe the recent evolution of surgery for the various types of pediatric megaureter. RECENT FINDINGS: Megaureter management first relies on determining the underlying cause, whether by obstruction, reflux, or a combination, and then setting appropriate surgical indications because many cases do not require surgery as shown by observation studies. Endoscopic balloon dilation has been on the rise as a major treatment option for obstructive megaureter, while refluxing megaureters can also be treated by laparoscopic and robotic techniques, whether extravesically or transvesicoscopically. During ureteral reimplantation, tapering is sometimes necessary to address the enlarged ureter, but there are also considerations for not tapering or for tapering alternatives. Endoscopic and minimally invasive surgeries for megaureter have been the predominant focus of recent megaureter literature. These techniques still need collaborative prospective studies to better define which surgeries are best for patients needing megaureter interventions.

Single-port-plus-one robot-assisted laparoscopic Lich-Gregoir direct nipple ureteral extravesical reimplantation in pediatric primary obstructive megaureter, comparing to laparoscopic cohen.

PURPOSE: To compare the effects of a single-port-plus-one robotic laparoscopic-modified Lich-Gregoir direct nipple approach and traditional laparoscopic Cohen in treating pediatric primary obstructive megaureter. MATERIALS AND METHODS: The clinical data of 24 children with primary obstructive megaureter from January 2021 to November 2021 were analyzed retrospectively. Among them, 12 children (8 boys and 4 girls, the average age were 17.17 ± 6.31 months) treated with the laparoscopic Cohen method were defined as group C. The remaining 12 children (7 boys and 5 girls, the average age was 17.33 ± 6.99 months) underwent single-port-plus-one robotic laparoscopic-modified Lich-Gregoir direct nipple ureteral extravesical reimplantation were defined as group L. The parameters of pre-operation, intraoperative and postoperative were compared. RESULTS: There were no differences in the patient characteristics and average follow-up time between the two groups (P > 0.05).The obstruction resolution rate was 100% in both groups. The total operation time in group L is slightly longer than that in group C(P < 0.001),but the intraperitoneal operation time of the two groups was comparable(P > 0.05). The postoperative parameters included blood loss, gross haematuria time, indwelling catheterization time and hospitalization time in group L is shorter than group C(P < 0.05). One year post-operation, decreasing in ureteral diameter and APRPD, and increasing in DRF were remarkably observed in both two groups(P < 0.05). Ureteral diameter, APRPD, and DRF were not significantly different both in pre-operation and post-operation between Group L and Group C(P > 0.05). CONCLUSION: Single-port-plus-one robot-assisted laparoscopic-modified Lich-Gregoir direct nipple approach and traditional laparoscopic Cohen are both dependable techniques for ureteral reimplantation in the treatment of pediatric primary obstructive megaureter. Since Lich-Gregoir can preserve the physiological direction of the ureter and direct nipple reimplantation enhances the effect of anti-refluxing, this technique is favorable for being promoted and applied in robot surgery.

Endoscopic dilatation/incision of primary obstructive megaureter. A systematic review. On behalf of the EAU paediatric urology guidelines panel.

INTRODUCTION: Historically, ureteral reimplantation (UR) has been the gold standard for treatment of primary obstructive megaureter (POM) with declining renal function, worsening obstruction, or recurrent urinary tract infections. In infants, open surgery with reimplantation of a grossly dilated ureter into a small bladder, can be technically challenging with significant morbidity. Therefore, less invasive endoscopic management such as dilatation or incision of the ureter-vesical junction, has emerged as an alternative to reimplantation during the last decades. OBJECTIVE: To systematically evaluate the effectivity, safety, and potential benefits of endoscopic treatment (dilatation with or without balloon or incision) of POM in comparison to UR. STUDY DESIGN: A systematic review was conducted. Randomized controlled trials (RCTs), nonrandomized comparative studies (NRSs), and single-arm case series including a minimum of 20 participants and a mean follow-up more than 12 months were eligible for inclusion. RESULTS: Of 504 articles identified, 8 articles including 338 patients were eligible for inclusion (0 RCTs, 1 NRSs, and 7 case series). Age at time of surgery was minimum 15 days to a maximum of 192 months. Indications for endoscopic treatment (ET) included patients with loss of split renal function (>10%) and worsening of hydroureteronephrosis. The studies analysed reported a success rate ranging from 35% to 97%. Success was defined as stabilization of differential renal function without further procedures. A post-operative complication rate of 23-60% was reported (mostly transient haematuria, urinary tract infections and stent migration or intolerance). In 14% of the cases salvage UR following initial ET, was performed due to relapse of symptomatic POM. CONCLUSION: Endoscopic treatment for persistent or progressive POM in children is a minimally invasive alternative to UR with a long-term modest success rate. Additionally, it can be performed within a wide age span, with equal success rate and complication rates.

Endoscopic treatment of primary obstructive megaureter with high pressure balloon dilation in infants.

INTRODUCTION AND OBJECTIVE: Ureteral reimplantation of the dilated ureter in infants is challenging; however, some patients with primary obstructive megaureter (POM) in this age group require intervention due to clinical or radiological progression. We sought to determine if high pressure balloon dilation (HPBD) can serve as a definitive treatment for POM in children under one year of age, or as a temporizing measure until later reimplantation. MATERIALS AND METHODS: All patients from a single institution who underwent HPBD between October 2009 and May 2022 were retrospectively reviewed. Patients were excluded if older than 12 months or diagnosed with neurogenic bladder, posterior urethral valves, or obstructed refluxing megaureter. Patients with prior surgical intervention at the ureterovesical junction were excluded. Indications for surgery included progressive hydroureteronephrosis or urinary tract infection (UTI). Balloon dilation was performed via cystoscopy with fluoroscopic guidance, followed by placement of two temporary ureteral stents. Primary outcomes were improvement or resolution of megaureter and rates of subsequent reimplantation. Secondary outcomes included total number of anesthetics and postoperative UTIs. RESULTS: Fifteen infants with median age of 7.6 months (IQR 3.8-9.7) underwent HPBD. Twelve (80%) patients were detected prenatally and 3 (20%) after a UTI. Indication for surgery was progressive hydroureteronephrosis in 10 patients (67%) and UTI in five (33%). All had SFU grade 3 or 4 hydronephrosis on preoperative ultrasound and median distal ureteral diameter was 13 mm. Median follow up was 2.9 years. Twelve (80%) succeeded with endoscopic treatment: 7 patients had an undetectable distal ureter on ultrasound at last follow-up, 5 were improved with median distal ureteral diameter of 7 mm. Three patients (20%) required ureteral reimplantation due to progressive dilation, all with grade 4 hydronephrosis and distal ureteral diameters were 11, 15, and 21 mm. Six patients (40%) required two anesthetics to complete endoscopic treatment. Among those, 4 patients required initial stent placement for passive dilation followed by a second anesthetic for HPBD weeks later. Two patients underwent repeat HPBD following postoperative proximal migration of the ureteral stents. All 15 patients had an additional anesthetic for removal of stents. Five patients (33%) were treated for a symptomatic UTI (4 febrile, 1 afebrile) with the stents indwelling but there were no UTIs in the group following stent removal. CONCLUSION: Balloon dilation is a practical option for treatment of POM in infants, and in most cases (80%) avoids subsequent open surgery (over median 2.9 years of follow-up).

Single-port-plus-one robot-assisted laparoscopic modified Lich-Gregoir direct nipple ureteral extravesical reimplantation in children with a primary obstructive megaureter.

Purpose: To introduce a new technique of single-port-plus-one robotic laparoscopic-modified Lich-Gregoir direct nipple ureteral extravesical reimplantation and ascertain its validity in the treatment of pediatric primary obstructive megaureter. Methods: Between January 2021 and November 2021, we retrospectively analyzed the clinical data of 12 children with primary obstructive megaureter who were admitted to the Department of Pediatric Surgery of Fujian Provincial Hospital. All 12 children were treated with single-port-plus-one robotic laparoscopic Lich-Gregoir direct nipple ureteral extravesical reimplantation. Five of them were female and seven were male, including nine cases were simple obstructive type, while the remaining three cases were obstructive with reflux type. The mean age of the children was 17.33 ± 6.99 (10-36) months and the mean follow-up time was 14.16 ± 1.75 (12-17) months. Changes in preoperative and first-year postoperative parameters were compared. Results: The mean operative time for all 12 children was 123.58 ± 10.85 (110-145) min, with a mean internal operative time of 101.42 ± 0.85 (90-120) min, a mean operative bleeding time of 2.42 ± 0.67 (2-4) ml, and a mean hematuria duration of 16.08 ± 1.44 (14-19) h. The mean indwelling catheterization time was 2.25 ± 0.45 (2-3) days and the mean hospitalization time was 3.83 ± 0.39 (3-4) days. At the postoperative first year, the ureteral diameter, calyceal diameter, and anterior-posterior renal pelvic diameter were found to be significantly smaller than at the preoperative period (18.83 ± 3.21 mm vs. 6.83 ± 1.27 mm, 13.99 ± 3.58 mm vs. 3.5 ± 2.90 mm, and 34.92 ± 4.25 mm vs. 10.08 ± 1.88 mm, P < 0.001). There was a significant increase in renal cortical thickness and the percentage of differential renal function (3.63 ± 1.66 mm vs. 5.67 ± 1.88 mm, 33.75 ± 2.77 mm vs. 37.50 ± 1.31 mm, P < 0.001). The resolution rate of obstruction was 100% and no child developed DeNovo vesicoureteral reflux. Conclusion: The technique of modified Lich-Gregoir direct nipple ureteral extravesical reimplantation can help maintain the physiological direction of the ureter and at the same time enhance the effectiveness of antirefluxing in robotic surgery. The design of a single-port-plus-one wound can produce a cosmetic appearance by concentrating and hiding the wound around the umbilicus. This modified reimplantation procedure has the potential to become a promising technique in the robot-assisted treatment of primary obstructive megaureter.

Endoscopic balloon dilation of primary obstructive megaureter: is fluoroscopic guidance necessary?

OBJECTIVE: To compare the long-term effectiveness, complications, and outcomes of primary obstructive megaureter (POM) treated by endoscopic balloon dilation under fluoroscopic guidance versus not using radioscopy during the procedure. PATIENTS AND METHODS: A comparative study between POM cases treated at our institution by endoscopic balloon dilation (EBD) under fluoroscopic guidance (FG) (n = 43) vs no fluoroscopic guidance (NFG) (n = 48) between the years 2004 and 2018 was conducted. The procedure in FG consisted of performing a retrograde pyelography before dilation. Then, a guidewire is introduced to the renal pelvis, and the dilation of the vesicoureteral junction is performed using high-pressure balloon catheters under fluoroscopic vision. Finally, a double-J stent is placed between the renal pelvis and bladder. The procedure in NFG was performed exclusively under cystoscopic vision without radiological exposure. Complications, outcomes, and success rates were analyzed using Spearman's correlation test. Mean follow-up was 12.5 ± 2.2 years in FG and 6.4 ± 1.3 years in NFG. RESULTS: MAG-3 showed significant differences in renal drainage before and after endoscopic treatment in both groups (p < 0.001 T-test). Statistical analysis did not reveal differences between groups in initial technical failure (r: - 0.035, p = 0.74), early postoperative complications (r: - 0.029, p = 0.79), secondary VUR (r: 0.033, p = 0.76), re-stenosis (r: 0.022, p = 0.84), long-term ureteral reimplantation (r: 0.065, p = 0.55), and final outcome (r: - 0.054, p = 0.61). The endoscopic approach of POM had a long-term success rate of 86.5% in FG VS 89.6% in NFG. CONCLUSIONS: Endoscopic balloon dilation of POM can be done with no radiation exposure with similar results, effectiveness, and outcomes.

Ureteral dilation recovery after intravesical reimplantation in children with primary obstructive megaureter.

Background: To observe the postoperative recovery following ureteral dilation in primary obstructive megaureter (POM) after ureteral implantation, and evaluate the risk factors affecting ureter diameter resolution. Materials and Methods: A retrospective study was performed in patients with POM who underwent ureteral reimplantation using the Cohen procedure. Patient characteristics, perioperative parameters, and postoperative outcomes were also analysed. A widest ureteral diameter of <7 mm was defined as a normal shape and outcome. Survival time was defined as the time from surgery to ureteral dilation recovery or to the last follow-up. Results: A total of 49 patients (54 ureters) were included in the analysis. The survival time ranged from 1 to 53 months. The shapes of a total of 47 (87.04%) megaureters recovered, and most (29/47) resolutions happened within 6 months after surgery. In the univariate analysis, bilateral ureterovesical reimplantation (p = 0.015), ureteral terminal tapering (p = 0.019), weight (p = 0.036), and age (p = 0.015) were associated with the recovery time of ureteral dilation. A delayed recovery of ureteral diameter was noted in bilateral reimplantation (HR = 0.336, p = 0.017) using multivariate Cox regression. Conclusions: Ureteral dilation in POM mostly returned to normal within six postoperative months. Moreover, bilateral ureterovesical reimplantation is a risk factor for delayed postoperative recovery of ureter dilation in POM.

Endoscopic balloon dilatation for the treatment of primary obstructive megaureter <24 months of age: Does the size of the balloon influence results?

INTRODUCTION: Endoscopic balloon dilatation (EBD) can be performed with different catheters and its durability is still controversial. This study aimed to compare long-term results of EBD performed <24 months of age using balloons of 4 mm vs. 6 mm in diameter. MATERIALS AND METHODS: Retrospective study of consecutive patients with unilateral primary obstructive megaureter (POM) undergoing EBD <24 months of age by two surgeons from 01/2009 to 12/2020. The technique was consistent, but for balloon diameter, which was 4 mm in group A vs. 6 mm in group B. End-points included peri-operative complications, success rate (improving dilatation and non-obstructive drainage on 9-month scintigraphy), and long-term outcome (need for reimplantation and diameter of retrovesical ureter at last ultrasound). RESULTS: The procedure was completed in all planned patient. Group A included 15 patients and Group B 30 patients. Groups were not significantly different for age (p < 0.09), gender (p < 0.1), laterality (p < 0.7), and preoperative median ureteral diameter (p = 0.08). No perioperative complications occurred. Four group A patients required a cutting balloon to achieve a satisfactory dilatation of the vesicoureteral junction (p = 0.009). After a median (range) follow-up of 70 (19-155) months, success rate was 73.3% vs. 83.3% (p = 0.45), 4/15 group A and 5/30 group B patients required reimplantation within 2 years of EBD. In successful cases, median (range) ureteral diameter at last follow-up was 6 (0-17) mm vs. 5 (0-14) mm, which was significantly better than preoperative value (p = 0.003 and p < 0.001, respectively), but not significantly different (p = 0.8) between groups. DISCUSSION: EBD is an umbrella term that encompasses many technical variations, which can be key for success. Although limited by the small numbers and the comparison of patients treated over two subsequent periods, this is the first study focusing on the role of balloon size. CONCLUSIONS: The diameter of the balloon did not influence significantly long-term results, but the 6 mm balloon slightly increased the success rate of EBD to 83.3% and eliminated the need for cutting balloons to achieve a satisfactory dilatation.

Modified technique for robot-assisted laparoscopic infantile ureteral reimplantation for obstructive megaureter.

PURPOSE: To describe a novel modification of technique to improve efficacy of robot-assisted laparoscopic extravesical ureteral reimplantation (RALUR-EV) in infants. MATERIALS AND METHODS: Between April 2017 and July 2019, sixteen infants with primary obstructive megaureter (POM) (Age range: 4-12 months) underwent robot-assisted ureteral reimplantation were reviewed in this series. In addition to the conventional Lich-Gregoir technique, the detrusor tunnel has been extended to the mobilized anterior bladder wall to guarantee sufficient tunnel length/ureter diameter ratio and avoid ureteral angulation. All patients underwent repeated ultrasound, diuretic renal dynamic imaging and voiding cystourethrography (VCUG) perioperatively and the outcomes were documented. RESULTS: All operations were completed with robotic assisted approach without conversion. Bilateral and unilateral reimplantation were respectively performed in two and fourteen patients. The mean operative time was 115.0 ± 19.5 min and the mean blood loss was 10.0 ± 1.8 ml. There were no high-grade complications (III-IV on Clavien-Dindo classification) except for one patient. The distal ureteric diameter was reduced from pre operative 1.7 ± 0.5 to 0.6 ± 0.5 cm 6 months post operatively (p < 0.05). One child (6.3%) required the second reimplantation for stenosis. The overall operative success rate was 94.4% (17 of 18 ureters) with a mean follow-up of 15.9 ± 7.4 months with no flux detected. CONCLUSION: Our preliminary experience suggests that our modified robot-assisted laparoscopic extravesical ureteral reimplantation is feasible in infants with good results.

Postoperative JJ stent is not necessary after balloon high-pressure endoscopic dilatation of primary obstructive megaureter.

INTRODUCTION: A wide range of surgical interventions have been described for the management of primary obstructive megaureter (POM). Endoscopic balloon dilatation has been developed through last decades as a minimally invasive alternative to classic surgery. OBJECTIVE: To assess the need for placement of a double J stent after endoscopic balloon dilatation procedure, by comparing the post-operative related outcomes with and without double J placement. Secondary outcome was the success rate, considering the need for further procedure after endoscopic balloon dilatation and the improvement of the ureteral diameter in the two groups. STUDY DESIGN: Historical retrospective comparison of children treated by endoscopic dilatation for POM, with post-operative JJ stent left in place (2012-2014) or without ureteral JJ stent (since 2015). Post-operative complications were reported following Clavien-Dindo grading system and compared between the two groups. Success rate was defined as absence of need for further surgical reimplantation. Ureteral diameters on preoperative and postoperative renal ultrasounds were compared. RESULTS: Endoscopic dilatations were performed in 42 patients for 46 renal units during the study period. There was a significantly higher rate of post-operative complications in the group with JJ stenting compared to the group without double J stenting regarding all Clavien-Dindo grades (56% vs 15%, p = 0.014) and Clavien-Dindo grade III only (31% vs 0%, p = 0,0051) (Figure). The success rate was similar in the JJ group (75%, F-up: 70 months [13-101]) and the no JJ group (81%, F-up: 26 months [12-95]). There was a significant improvement of US renal pelvis and ureter dilatation in both groups, with a median follow-up of 35.5 months [12-101]. DISCUSSION: The overall rate of complications was slightly higher than in other reports and higher in the JJ group regarding Clavien-Dindo grade III complications. The success rate was comparable to previous studies reviewing endoscopic dilatations and equivalent in the two groups. CONCLUSION: In our study, the omission of postoperative ureteral drainage by a JJ stent after endoscopic balloon dilatation of POM did not increase post-operative complications rate without demonstrable impact on the success rate.

Pneumovesicoscopic ureteral reimplantation with intravesical tailoring of obstructive megaureter in pediatric patient.

INTRODUCTION: According to available data, there are only few articles describing pneumovesicoscopic (PNV) ureteral reimplantation (UR) for obstructive megaureter without tailoring and with ex vivo tailoring in children. AN OBJECTIVE: To present our experience of the PNV UR using intravesical ureteral tailoring for symptomatic primary obstructive megaureter in children. STUDY DESIGN: Between 2014 and 2020, 42 patients (mean age: 3.1 years) underwent a correction of primary obstructive megaureter (POM) via a vesicoscopic approach. Nine of them with the megaureter (diameter > 25 mm) underwent the intravesical ureteral tailoring. The analysis included only 9 patients who underwent intravesical tailoring of the ureter using the original technique. The dilated ureter is fixed intravesical by the loop in extended position. This simplifies the tailoring step of the ureter. The tailoring is performed by continuous suture (Star). RESULTS: 43 UR were analyzed (1 bilateral, 1 with diverticulum, 1 with ureterocele). The mean operative time was 142 min (83-235 min). The mean manipulation time for intravesical tailoring of the megaureter was 18 min. After the surgery, the average kidney function doesn't reduce. We observed an increase in renal function by an average of 7% in three patients after the surgery. One patient required a conversion. It was in the early stages of mastering the technique. All patients underwent US 1-3 weeks 3-6-12 months after the operation, the size of the pelvic system and ureter decreased. Eight patients are asymptomatic, and only one has the clinical changes (a persistent leukocyturia, the size of the pelvic-ureteric segment, and the ureter remain unchanged or increased). According to the VCUG vesicoureteral reflux was detected in this case. An endoscopic correction used successful. DISCUSSION: This possibility of applying our technique is confirmed according to folow-up data and should be used in other researches. The drainage of the ureter with an external stent for 1 month helps to form properly the neo-ureterovesical anastomosis and to prevent episodes of ureteral obstruction as a result the incidence of urinary tract infections reduces in the postoperative period. CONCLUSIONS: The use of the Tuohy needle with the loop simplifies the fixation of the ureter. This helps to make the intravesical tailoring of the megaureter easier and faster. It is original and less traumatic for the ureter than existing methods.

Ureteral Reimplantation for Primary Obstructive Megaureter in Pediatric Patients: Is It Time for Robot-Assisted Approach?

Objective: To compare open and robotic approach for treatment of Primary Obstructive Megaureter (POM) in a series of pediatric patients. Materials and Methods: Medical records of all patients who had undergone ureteral reimplantation for POM at our institution, between January 2016 and December 2019, were retrospectively collected and analyzed. Open (Group B) and robotic (Group A) approach were compared. Success was defined as reduction of anteroposterior diameter of pelvis and ureter on postoperative ultrasound scan. Surgical complications were reported according to the Clavien-Dindo Classification. Esthetic results were compared through the Vancouver Scar Scale. Results: Out of 23 patients, 11 belonged to Group A (5M and 6F) and 12 to Group B (9M and 3F). Median age at diagnosis was 38 months in Group A and 46 months in Group B (P = .69). Operative times were comparable (150' Group A and 140' Group B; P = .35), but the hospital stay was significantly shorter in the robotic group (P < .01). Success rate was comparable: 90.9% in Group A and 91.7% in Group B, respectively (P = .95). Incidence of early complications was 9.1% in Group A (grade IIIB) and 8.3% in Group B (grade II) (P = .95). Esthetic evaluation obtained a median score of 1 in Group A and 3 in Group B (P < .01). Conclusions: Our preliminary experience shows that robotic reimplantation can be a safe option in the treatment of POM in pediatric patients with clinical outcomes comparable to the open technique.

Minimally invasive ureteral reimplantation or endoscopic management for primary obstructive megaureter: a narrative review of technical modifications and clinical outcomes.

Background and Objective: Primary obstructive megaureter (POM) has various courses in different age populations. Although open ureteral reimplantation (OUR) remains the standard treatment for symptomatic POM, it is highly invasive with potential complications. In recent years, minimally invasive ureteral reimplantation (MIUR), including laparoscopic ureteral reimplantation (LUR) and robotic-assisted laparoscopic ureteral reimplantation (RALUR), and endoscopic management, such as double-J stent insertion, endoureterotomy and endoscopic balloon dilatation (EBD), have been utilized for POM in selected patients. However, few comparable studies between MIUR and endoscopic management have been published to date, and it remains unclear which surgical management is the optimal choice for POM in different age groups. This review provides a comprehensive perspective on technical development and clinical outcomes of MIUR and endoscopic management for POM in pediatric and adult populations. Methods: The PubMed and Web of Science databases were used to comprehensively search English language articles related to MIUR and endoscopic management for POM in pediatric and adult populations up to March 2022. The technical modifications and the relevant clinical outcomes were reviewed. Key Content and Findings: MIUR with various technical modifications related to intracorporeal suturing and ureteroneocystostomy with anti-reflux techniques appears to be as safe and effective for POM in different age groups as the open procedure. Double-J stent insertion should be regarded as a temporary option for infants by achieving internal urinary drainage, as it may present limited success rates and various complications. Endoureterotomy using pure cutting current or laser appears to be a safer, easier, and less invasive alternative to open surgical management. While EBD has emerged as a definite treatment for POM in the pediatric population, it is debatable whether EBD can substitute for MIUR in adult patients. Conclusions: The safety and feasibility of MIUR and endoscopic management in patients from all age groups still need further investigation.

Antegrade endoscopic dilatation as an alternative approach to primary obstructive megaureter. / Dilatación endoscópica anterograda como abordaje alternativo del megauréter obstructivo primario.

OBJECTIVES: Congenital primary obstructive megaureter (POM) is caused by ureterovesical junction stenosis, reduced peristalsis, and the resulting dilatation. Even though ureteral re-implantation remains the current gold standard technique, retrograde dilatation is considered as an effective therapeutic alternative with good results and growing proponents - to the extent it has become the technique of choice in some healthcare facilities. The objective was to present an alternative approach for treatment purposes. MATERIALS AND METHODS: This is the case of a 5-month-old infant with POM and pyonephrosis requiring nephrostomy and intravenous antibiotic therapy. Endoscopic dilatation was carried out by means of a percutaneous drainage in an antegrade fashion and did not require cystoscopy. RESULTS: The procedure was uneventful. During follow-up, ureterohydronephrosis decreased, while ureteral dilatation persisted to a lesser extent with an adequate peristalsis and absence of secondary VUR. The patient has had no symptoms after an 11-month follow-up. CONCLUSIONS: POM antegrade dilatation is an effective alternative in selected patients as it makes the pathology disappear.

OBJETIVOS: El megauréter obstructivo primario congénito (MOP) se produce por la estenosis de la unión ureterovesical, disminución en la peristalsis y su consecuente dilatación. Aunque actualmente el gold standard para el tratamiento de esta entidad sigue siendo el reimplante ureteral, la dilatación retrógrada se considera una alternativa terapéutica eficaz con buenos resultados y que está ganando cada vez más adeptos, siendo en algunos centros la técnica de elección. El objetivo es presentar una alternativa de abordaje para su tratamiento. MATERIAL Y METODOS: Se presenta el caso de un lactante de 5 meses con MOP afecto de pionefrosis que precisa nefrostomía y antibioterapia endovenosa. La dilatación endoscópica se realizó a través del drenaje percutáneo de manera anterógrada sin necesidad de cistoscopia. RESULTADOS: El procedimiento se llevó a cabo sin incidencias. En el seguimiento se apreció una disminución de la ureterohidronefrosis, persistiendo la dilatación del uréter en menor grado con adecuada peristalsis y la ausencia de RVU secundario. Tras 11 meses de seguimiento, permanece asintomático. CONCLUSIONES: La dilatación anterógrada del MOP es una alternativa efectiva en pacientes seleccionados que permite la resolución de la patología.

Dilatación endoscópica anterograda como abordaje alternativo del megauréter obstructivo primario / Antegrade endoscopic dilatation as an alternative approach to primary obstructive megaureter

Objetivos: El megauréter obstructivo primario congénito (MOP)se produce por la estenosis de la unión ureterovesical, disminución enla peristalsis y su consecuente dilatación. Aunque actualmente el goldstandard para el tratamiento de esta entidad sigue siendo el reimplanteureteral, la dilatación retrógrada se considera una alternativa terapéuticaeficaz con buenos resultados y que está ganando cada vez más adeptos,siendo en algunos centros la técnica de elección. El objetivo es presentaruna alternativa de abordaje para su tratamiento. Material y métodos: Se presenta el caso de un lactante de 5 mesescon MOP afecto de pionefrosis que precisa nefrostomía y antibioterapiaendovenosa. La dilatación endoscópica se realizó a través del drenajepercutáneo de manera anterógrada sin necesidad de cistoscopia. Resultados: El procedimiento se llevó a cabo sin incidencias. Enel seguimiento se apreció una disminución de la ureterohidronefrosis,persistiendo la dilatación del uréter en menor grado con adecuada peristalsis y la ausencia de RVU secundario. Tras 11 meses de seguimiento,permanece asintomático. Conclusiones: La dilatación anterógrada del MOP es una alternativa efectiva en pacientes seleccionados que permite la resoluciónde la patología.

Objectives: Congenital primary obstructive megaureter (POM) iscaused by ureterovesical junction stenosis, reduced peristalsis, and theresulting dilatation. Even though ureteral re-implantation remains thecurrent gold standard technique, retrograde dilatation is considered asan effective therapeutic alternative with good results and growing proponents – to the extent it has become the technique of choice in somehealthcare facilities. The objective was to present an alternative approachfor treatment purposes Materials and methods. This is the case of a 5-month-old infantwith POM and pyonephrosis requiring nephrostomy and intravenousantibiotic therapy. Endoscopic dilatation was carried out by means ofa percutaneous drainage in an antegrade fashion and did not requirecystoscopy. Results: The procedure was uneventful. During follow-up, uretero-hydronephrosis decreased, while ureteral dilatation persisted to a lesserextent with an adequate peristalsis and absence of secondary VUR. Thepatient has had no symptoms after an 11-month follow-up. Conclusions: POM antegrade dilatation is an effective alternativein selected patients as it makes the pathology disappear.(AU)

Long-term safety and efficacy of psoas bladder hitch in infants aged <12 months with unilateral obstructive megaureter.

OBJECTIVE: To determine the long-term safety and efficacy of ureteric reimplantation with psoas bladder hitch (PBH) in patients aged <12 months with unilateral obstructive megaureter (OM). PATIENTS AND METHODS: We retrospectively compared a group of patients aged <12 months (study group) with an group of patients aged ≥12 months (comparison group), who underwent PBH for OM between September 2007 and April 2017, in terms of preoperative patient characteristics, intra- and peri-operative results, and postoperative results. RESULTS: The study group comprised seven infants, five boys and two girls. The median (range) age at the time of PBH was 3 (2-8) months; OM was detected by ultrasonography during the fetal period. The left side was affected in four infants and the right side in three. Four infants had primary OM (POM). In all three infants who had ectopic OM in the complete double renal pelvis and ureter, the OM involved the ureter from the upper half of the kidney. The median (range) follow-up period after PBH was 45 (33-129) months. Comparison of the two groups showed no significant difference in terms of surgical time (P = 0.948) and length of hospital stay (P = 0.125). In both groups, hydroureteronephrosis improved postoperatively in all patients. There was no significant difference between the two groups in terms of postoperative complications, such as vesico-ureteric reflux, febrile urinary tract infection and deterioration of ipsilateral renal function. Notably, no patient underwent reoperation in either group. CONCLUSION: Psoas bladder hitch for unilateral OM including POM appears to be safe and effective in the long term for patients aged <12 months and for those aged ≥12 months. Although not routinely recommended, PBH appears to be a viable option for selected infants with POM.

A Novel Surgical Technique for Obstructed Megaureter: Robot-Assisted Laparoscopic Dismembered Extravesical Cross-Trigonal Ureteral Reimplantation-Short-Term Assessment.

Purpose: To describe our experience with robot-assisted laparoscopic dismembered extravesical cross-trigonal ureteral reimplantation (RADECUR)-a novel minimally invasive surgical technique for treatment of obstructed megaureter. Materials and Methods: A retrospective review of our prospectively collected data, of all pediatric patients who underwent unilateral RADECUR for the treatment of primary or secondary obstructed megaureter at two medical centers during a 3-year period. Patient demographics, perioperative data, surgical technique, complications, and results are described. Results: Thirty-five pediatric patients underwent RADECUR between January 2016 and May 2019. Median age and weight at surgery were 28 months (interquartile range [IQR]: 20-58) and 20 kg (IQR: 13-27), respectively. There were no conversions to an open procedure. Median console time was 100 minutes (IQR: 90-125). Ten patients underwent intracorporeal excisional tapering of the obstructed ureter. Mean pre- and postoperative ureteral diameters were 14.5 mm (IQR: 12-18) and 7 mm (IQR: 0-10), respectively (p < 0.0001). All but one patient demonstrated a reduction in hydronephrosis and ureteral diameter on follow-up ultrasonography. Grade 1-2 Clavien-Dindo complications occurred in five patients (14%) and another patient developed a grade 3 complication. Three patients developed postoperative febrile urinary tract infection, one of them was found to have high-grade reflux and subsequently underwent open ureteral reimplantation. Conclusions: Unilateral robotic extravesical cross-trigonal ureteral reimplantation for treatment of obstructed megaureter in the pediatric population is safe and effective. Further larger scale comparative studies with other surgical techniques are needed to determine the role of RADECUR in the armamentarium of treatment for distal ureteral obstruction.