Are weight or age limits for pediatric laparoscopic pyeloplasty? Results of a multicentric study.

INTRODUCTION: Anderson-Hynes pyeloplasty is the technique of choice for the treatment of pyeloureteral junction obstruction (PUJO) with an excellent success rate. Minimally invasive surgery has become the standard of care for the management of PUJO in children. Although it has been comparable to the open approach at all levels, its diffusion or employment in younger children has not been widely adopted. Our aim is to evaluate laparoscopic pyeloplasty outcomes from international academic centers in children under 1 year of age, focusing on feasibility and outcomes including possible complications. MATERIALS AND METHODS: This is review of consecutive infants under 1 year of age who underwent laparoscopic pyeloplasty between 2009 and 2018 with more than 12 months of follow-up. Seven different training centers with different backgrounds participated in this study. Evaluation was carried out with ultrasound and renogram before and after surgery. Demographic data, perioperative characteristics, complications, and results are described and analyzed. RESULTS: Over 9 years, 124 transperitoneal laparoscopic Anderson-Hynes pyeloplasties were performed on 123 children under 1 year of age; 88 males and 35 females, with 1 case of bilateral PUJO. Of the 124 renal units, 86 were left-sided. Mean age at surgery was 6.6 months (1 week-12 months), with 56% (n = 70) done before 6 months of age. Mean weight at surgery was 6.8 kg (3-12 kg), with 59% (n = 73) weighing less than 8 kg. Mean operative time (skin-to-skin) was 150 min (75-330 min). After a mean follow-up of 46 months (12-84 months), 12 (9%) patients developed complications, with only 1 needing a redo pyeloplasty also done laparoscopically. One child, with deterioration in renal function, underwent nephrectomy. CONCLUSION: Laparoscopic pyeloplasty under 1 year of age and/or less than 12 kilos is feasible with lower complication rate. Furthermore, age younger than 6 months and weight less than 8 kg are no longer limiting factors for a successful pyeloplasty as shown by this multicentre study.

Relation between Cajal Cell Density and Radiological and Scintigraphic Outcomes in Patients with Ureteropelvic Junction Obstruction.

INTRODUCTION: In this study, we aimed to investigate the correlation between Cajal cell density and preoperative and postoperative radiological and scintigraphic parameters in ureteropelvic junction obstruction (UPJO). METHODS: The study group consisted of 41 renal units (38 consecutive patients; 13 female and 25 male) surgically treated for UPJO. UPJ specimens from patients were immuno-stained with CD117 (c-kit) antibody for interstitial Cajal cells (ICCs). The relation between Cajal cell density and preoperative and postoperative radiological and scintigraphic parameters was evaluated. RESULTS: The mean age of the patients was 8.52 ± 8.86 (0-35) years. The density of Cajal cells was defined in 2 groups for convenient analysis as 0-5 cells (low) in 19 (46.3%) patients and >5 cells (moderate-high) in 22 (53.6%). There was significant difference between the preoperative and postoperative anteroposterior diameters of the related kidneys in both Cajal groups (p = 0.001-low, p = 0.000-moderate-high) independent of Cajal cell density. Regression in hydronephrosis postoperatively was determined in both Cajal groups (77.8%-low, 64.7%-moderate-high); however, there was no difference between them (p = 0.39). Preoperative T1/2 was significantly longer in the low Cajal group (p = 0.02). Postoperative T1/2 decreased in both low (p = 0.000) and moderate-high (p = 0.001) Cajal groups, but no difference was found between them (p = 0.24). There was significant improvement in the kidney differential function after surgery in the low Cajal density group (p = 0.015) while there was no correlation between the scintigraphic success or improvement and Cajal cell density (p = 0.51). DISCUSSION/CONCLUSION: ICC deficiency/density could not be shown as a predictive factor for the determination of success rate of pyeloplasty. Despite the lack of any evidence for the degree of deficiency as an indicator for the severity of obstruction and prediction of surgical success, further studies are needed for confirmation.

Unilateral T-shaped incomplete duplex nephrectomy in an adolescent under laparoscopy: A case report.

INTRODUCTION: Duplicate kidneys are the most common congenital abnormality of the urinary system. The location of duplicate kidneys varies. We report a case of an adolescent with upper and lower kidneys that are arranged vertically and approximately T-shaped. PATIENT CONCERNS: A 16-year-old male teenager was examined for pain in the left side of the waist. The Computed Tomography scan revealed that the left kidney was incompletely duplicated and fused; the left upper urinary tract was incompletely obstructed. DIAGNOSIS: The abdominal tomography confirmed the diagnosis of incomplete duplicate kidney. INTERVENTIONS: The patient underwent laparoscopic surgery. The failure to ligate the renal pedicle resulted in increased bleeding during the operation and an open ureteral stump. OUTCOMES: No urine leakage occurred after the operation. Doppler ultrasound of the urinary system showed no hydronephrosis, and the patient was asymptomatic. CONCLUSION: Through this case report, we found that the duplicate kidneys could be arranged in a T-shape under laparoscopy. Although only the supply of the duplicate renal arteries can be ligated during surgical resection, the renal pedicle must also be ligated during the operation if there is a lot of bleeding.

Isolated iliac artery aneurysm in association with congenital pelvic kidney treated with iliac branch device: case report.

BACKGROUND: Association of abdominal aortic aneurysm with congenital pelvic kidney is rare and association with isolated iliac artery aneurysm is not yet described in the literature. CASE PRESENTATION: We present a case of successful repair of an isolated common iliac artery aneurysm associated with a congenital pelvic kidney treated by an endovascular technique. A 75-year-old man was referred for the treatment of an asymptomatic left common iliac artery aneurysm. A computed tomography angiography revealed an isolated left common iliac artery aneurysm and a left pelvic kidney. The maximum diameter of the aneurysm was 32 mm. The congenital pelvic kidney was supplied by three small superior polar arteries that emerged from the proximal non-aneurysmal portion of the common iliac artery and the main artery that arose from the left internal iliac artery. The aneurysm exclusion was accomplished by using an iliac branch device (Gore Excluder Iliac Branch, Flagstaff, AZ). The 1 and 6 months computed tomography angiography after the procedure demonstrated complete exclusion of the aneurysm and preservation of all renal arteries. CONCLUSION: Treating patients with an association of iliac artery aneurysms and pelvic kidneys can be a challenge due the variable arterial anatomy. The use of iliac branch device is a safe and effective alternative in selected cases.

Villous adenoma of the renal pelvis: a common entity at an uncommon location

Villous adenoma is uncommonly seen in the urogenital tract and is even more rarely seen in the upper urinary tract and renal pelvis. Like colorectal adenomas, these neoplasms can transform into adenocarcinoma. The preoperative diagnosis is challenging due to their frequent association with hydronephrosis. Herein, we present the case of a villous adenoma of the renal pelvis in a 62-year-old man presenting with recurrent urinary tract infection. The computed tomography scan showed marked hydronephrosis but no suspicious mass in the right kidney. A laparoscopic right nephrectomy was performed. Gross examination revealed a dilated renal pelvis with an irregular exophytic lesion in the renal pelvis's upper surface. The histopathological examination showed slender, elongated villi with thin fibrovascular cores, consistent with villous adenoma morphology. Isolated villous adenomas have a favorable prognosis. However, the pathologist should undertake a search for an invasive component.

Chimney technique for solitary pelvic kidney.

The combination of solitary pelvic kidney and abdominal aortic aneurysm is extremely rare. In this report, we present chimney graft implantation in a patient with solitary pelvic kidney. A 63-year-old man had the diagnosis of infrarenal abdominal aortic aneurysm made incidentally. Preoperative computed tomography illustrated a fusiform abdominal aortic aneurysm accompanying a solitary ectopic kidney in the pelvis with aberrant renal artery. A bifurcated endograft was implanted, and a covered stent graft was placed into the renal artery by use of the chimney technique. Good patency of the chimney graft was documented with early postoperative and first month scans. To the best of our knowledge, this is the first report of the chimney technique used in a solitary pelvic kidney.

Spontaneous subepithelial hemorrhage of renal pelvis and ureter (Antopol-Goldman lesion) in hemophilia A patient with inhibitor: Case report and review of the literature.

INTRODUCTION: The Antopol-Goldman lesion (AGL), which expresses subepithelial hemorrhage in the renal pelvis, was first defined by Antopol and Goldman in 1948. The objective of this study is to report the first case of AGL in patients with congenital hemophilia and review the relevant literature. PATIENT CONCERNS: A 32-year-old male patient diagnosed with congenital hemophilia A (FVIII = %4) with high responding inhibitors (7.4 BU) was admitted to our emergency department with gross hematuria and sudden onset flank pain. DIAGNOSIS: Abdominal computed tomography (CT-scan) presented a hyperdense lesion in the left ureteropelvic junction with Hounsfield Units of 56 compatibles with hemorrhage. INTERVENTIONS: The patient was given 4500 IU of factor eight inhibitor bypass activity (FEIBA) intravenously twice daily for 5 days. Subsequently, 4500 IU of FEIBA was administrated once a day for 2 days. OUTCOMES: The patient's complaints disappeared on the fourth day of treatment. Macroscopic and microscopic hematuria was not seen in the following days. Follow-up CT was done 3 months after discharge and showed normal left renal pelvis without hyperdenosis. Follow-up CT was performed 3 months after discharge and presented normal left renal pelvis with no hyperdense lesion. CONCLUSION: Although very rare, AGL should be kept in mind in the differential diagnosis of renal pelvic hemorrhage. In the patient who has an underlying history of coagulopathy nephrectomy can be avoided when there is awareness of AGL.

How often do we incidentally find a fetal abnormality at the routine third-trimester growth scan? A population-based study.

BACKGROUND: Third-trimester scans are increasingly used to try to prevent adverse outcomes associated with abnormalities of fetal growth. Unexpected fetal malformations detected at third-trimester growth scans are rarely reported. OBJECTIVE: To determine the incidence and type of fetal malformations detected in women attending a routine third-trimester growth scan. STUDY DESIGN: This was a population-based study of all women with singleton pregnancy attending antenatal care over a 2-year period in Oxfordshire, UK. Women who had a viable singleton pregnancy at dating scan were included. Women had standard obstetrical care including the offer of a routine dating scan and combined screening for trisomies; a routine anomaly scan at 18 to 22 weeks; and a routine third-trimester growth scan at 36 weeks. The third-trimester scan comprises assessment of fetal presentation, amniotic fluid, biometry, umbilical and middle cerebral artery Dopplers, but no formal anatomic assessment is undertaken. Scans are performed by certified sonographers or clinical fellows (n=54), and any suspected abnormalities are evaluated by a team of fetal medicine specialists. We assessed the frequency and type of incidental congenital malformations identified for the first time at this third-trimester scan. All babies were followed-up after birth for a minimum of 6 months. RESULTS: There were 15,244 women attending routine antenatal care. Anomalies were detected in 474 (3.1%) fetuses as follows: 103 (21.7%) were detected before the anomaly scan, 174 (36.7%) at the anomaly scan, 11 (2.3%) after the anomaly scan and before the third-trimester scan, 43 (9.1%) at the third-trimester scan and 143 (30.2%) after birth. The 43 abnormalities were found in a total of 13,023 women who had a 36 weeks scan, suggesting that in 1 out of 303 (95% confidence interval, 233-432) women attending such a scan, a new malformation was detected. Anomalies detected at the routine third-trimester scan were of the urinary tract (n=30), central nervous system (5), simple ovarian cysts (4), chromosomal (1), splenic cyst (1), skeletal dysplasia (1), and cutaneous lymphangioma (1). Most urinary tract anomalies were renal pelvic dilatation, which showed spontaneous resolution in 57% of the cases. CONCLUSION: When undertaking a program of routine third-trimester growth scans in women who have had previous screening scans, an unexpected congenital malformation is detected in approximately 1 in 300 women.

Utility of Society for Fetal Urology and Anteroposterior Pelvic Diameter Grading Systems for Estimating Time to Resolution of Isolated Hydronephrosis: A Single Center Study.

PURPOSE: We aimed to compare the Society for Fetal Urology and anteroposterior pelvic diameter classification systems in predicting the time to resolution of isolated hydronephrosis. MATERIALS AND METHODS: We retrospectively reviewed isolated hydronephrosis cases prenatally detected and postnatally diagnosed between 1994 and 2018. Other urinary tract anomalies and vesicoureteral reflux were excluded. Baseline grades for both systems were collected. Anteroposterior pelvic diameter was classified as grade 1 to 4 over a scale of 5 mm. Resolution was defined by an anteroposterior pelvic diameter of less than 5 mm with Society for Fetal Urology grade I hydronephrosis. Time to resolution was analyzed using Kaplan-Meier curves. RESULTS: The study population consisted of 831 patients (1,028 renal units). Median followup was 26 months (range 6 to 260), and 559 units (54.3%) reached resolution during a median followup of 9 months (1 to 133). Resolution rates at 48 months were 81.7%, 65.6%, 37.6% and 5.2% for Society for Fetal Urology grades I through IV disease and 80.0%, 41.2%, 13.1% and 2.5% for anteroposterior pelvic diameter grades 1 through 4, respectively. Discrepancies between these grades were present in 481 units (46.8%). Society for Fetal Urology grades II to IV categorized as anteroposterior pelvic diameter grade 1 showed a superior cumulative rate of resolution (84.7%) vs anteroposterior pelvic diameter grades 2 to 4 categorized as Society for Fetal Urology grade I (53.2%, log-rank test p <0.001). CONCLUSIONS: Hydronephrosis cases with anteroposterior pelvic diameter grades 2 to 4 but categorized as Society for Fetal Urology grade I have an inferior cumulative rate of resolution than vice versa. Society for Fetal Urology grades have little influence on resolution when anteroposterior pelvic diameter is less than 10 mm. Therefore, anteroposterior pelvic diameter is more useful in predicting the time to resolution.

Prenatal imaging features and postnatal outcomes of isolated fetal duplex renal collecting system: A systematic review and meta-analysis.

OBJECTIVES: To perform a systematic review of studies reporting the outcome of fetuses with a prenatal diagnosis of isolated duplex collecting system (DCS). METHODS: Inclusion criteria were studies reporting the outcome of fetuses with a prenatal diagnosis of isolated DCS, defined as DCS not associated with other major structural anomalies at the time of diagnosis. The outcomes observed were: imaging features of DCS on prenatal ultrasound, associated anomalies detected exclusively at prenatal follow-up ultrasound and at birth, abnormal karyotype, symptoms at birth (including vesicoureteral reflux [VUR] and urinary tract infections [UTI]), need for and type of surgical approach, complications after surgery, and accuracy of prenatal ultrasound in correctly identifying this anomaly. RESULTS: Eleven studies (284 fetuses with a prenatal diagnosis of DCS) were included. On ultrasound, DCS was associated with ureterocele in 70.7% and with megaureter in 36.6% of cases. Worsening of pelvic/ureteric dilatation was reported to occur in 41.3% of fetuses. At birth, 4.3% of fetuses affected by DCS showed associated renal anomalies. After birth, VUR and UTI presented in 51.3% and 21.7% of children respectively, while 33.6% required surgery. Prenatal diagnosis of DCS was confirmed in 90.9% of included cases. CONCLUSION: DCS diagnosed prenatally is associated with a generally good outcome. Prenatal ultrasound has a good diagnostic accuracy, while detailed postnatal assessment is required in order to identify associated renal anomalies.

Robot-assisted Partial Nephrectomy and Bilateral Pyelolithotomy in Ectopic Pelvic Kidneys.

OBJECTIVE: To show how to perform a robot-assisted partial nephrectomy and bilateral pyelolithotomy in ectopic pelvic kidneys. This is a congenital abnormality of position and rotation1 frequently associated with urolithiasis.2 Renal cell carcinoma is a very rare event in pelvic kidneys.3,4 These 2 findings in the same patient could be a surgical challenge and whenever possible a "one stage" treatment is preferred. MATERIALS AND METHODS: A 44-year-old male with bilateral pelvic kidneys admitted because of left back pain. Abdominal CT scan showed a 17 mm stone in the left renal pelvis, a 12 mm stones in the right pelvis and a 34 × 27 mm right lower pole renal mass. A robotic surgery was indicated. Patient was placed in Trendelenburg position with ports configuration as for transperitoneal radical prostatectomy. The right kidney was firstly approached: after isolation of the ureter and suspension of the renal artery, a clampless partial nephrectomy was performed; then through a longitudinal pyelotomy the stone was extracted. To minimize the opening of the posterior peritoneum covering the left kidney, the site of the stone was identified by intraoperative ultrasound; then, through a longitudinal pyelotomy the stone was extracted. Given the watertight sutures and the lack of ureteral obstructions no pigtails ureteral catheters were inserted. A Jackson-Pratt drainage was placed through the inferior port. RESULTS: Consolle time was 190 minutes. Estimated Blood Loss (EBL) was 50 ml. No complications were reported. The drain was removed on the second postoperative day, assessed that creatinine dosage was equal to serum. The length of stay was 4 days. Histopathology showed a pT1a G2 clear cell renal cell carcinoma with negative surgical margins, while stones analysis was calcium oxalate. CONCLUSION: With the availability of robotic technology, the indications for minimally invasive surgery may be safely expanded to include concomitant morbidities in uncommon presentations.

Relationship of renal apparent diffusion coefficient and functional MR urography in children with pelvicalyceal dilation.

OBJECTIVE: The aim is to evaluate the age-related changes and relationship of renal apparent diffusion coefficient (ADC) against the morphological and functional changes detected by functional magnetic resonance urography (fMRU) in children with pelvicalyceal dilation, with suspected or known ureteropelvic junction obstruction. MATERIALS AND METHODS: We retrospectively analyzed fMRUs with diffusion-weighted imaging (DWI) of the kidney in 35 subjects (25 males; median age: 7.1 years, range: 0.3-22.7 years) with 70 kidneys (40 with pelvicalyceal dilation and 30 with no pelvicalyceal dilation). Inclusion criteria were pelvicalyceal dilation, the absence of duplex kidneys and no ureteric dilation. DWI was performed with 3 diffusion gradient directions (b values = 0, 200, 500, 800 and 1,000 s/mm2). Metrics for fMRU included calyceal and renal transit times (CTT, RTT), time-to-peak (TTP), differential renal function based on volume (vDRF), Patlak number (pDRF) and combined volume and Patlak number (vpDRF). The grades of pelvicalyceal dilation, cortical thinning and corticomedullary differentiation were evaluated. The relationship between ADC values and the fMRU parameters was analyzed. RESULTS: ADC increases with age in kidneys without pelvicalyceal dilation (R2=0.37, P<0.001). Renal ADC does not correlate with any of the morphological or fMRU parameters (P>0.07). The median ADC of kidneys without pelvicalyceal dilation was 3.73×10-3 mm2/s (range: 2.78-5.37×0-3 mm2/s) and the median ADC of kidneys with pelvicalyceal dilation was 3.82×10-3 mm2/s (range: 2.70-5.70×10-3 mm2/s). There was no correlation between ADC and the absolute differences of vDRF or pDRF (P>0.33). CONCLUSION: Renal ADC does not correlate with morphological and functional results of fMRU changes in children with pelvicalyceal dilation due to suspected or known ureteropelvic junction obstruction.

Natural course of isolated mild congenital hydronephrosis: A 2-year prospective study at a single center in Japan.

OBJECTIVES: To determine a follow-up plan for mild congenital hydronephrosis in Japanese individuals. METHODS: Neonates at Kansai Medical University Hospital (Hirakata, Osaka, Japan) who were diagnosed with mild congenital hydronephrosis - defined as a Society for Fetal Urology grade 1 or 2 - at 1-month old by abdominal ultrasonography between 2014 and 2016 were enrolled. These patients were encouraged to undergo repeated abdominal ultrasonography for 2 years every 3 months to investigate the course of congenital hydronephrosis. RESULTS: Among 1009 neonates, congenital hydronephrosis was detected in 118 affected renal units of 100 (9.9%) patients. According to the definition of the Society for Fetal Urology, 118 affected renal units were graded as grade 1 in 87 (74%), grade 2 in 30 (25%), grade 3 in one (1%) and grade 4 in 0 units. Among them, 117 affected renal units of mild congenital hydronephrosis comprising grades 1 and 2 were subjected to ultrasonographic evaluation to monitor the natural course. The rates of resolution at 7, 10, 13, 16, 19, 22 and 25 months after birth in Society for Fetal Urology grades 1 and 2 cases were 60% and 8%, 77% and 19%, 90% and 32%, 92% and 40%, 95% and 52%, 96% and 56%, and 99% and 60%, respectively. CONCLUSIONS: Grade 1 congenital hydronephrosis does not need to be followed up, because it mostly shows spontaneous resolution by 2 years of follow up without any complications. However, ultrasonographic examinations at 1-year intervals for grade 2 congenital hydronephrosis are recommended to determine the subsequent follow-up plan of patients.

Value of renal pelvic diameter and urinary tract dilation classification in the prediction of urinary tract anomaly.

BACKGROUND: The aim of this study was to identify the cut-offs of postnatal anteroposterior renal pelvic diameter (APRPD), according to the urinary tract dilation (UTD) classification system, to identify the predictors of final diagnosis of UTD and the need for surgery. METHODS: A total of 260 infants (336 renal units) with prenatally detected UTD were prospectively evaluated on serial ultrasonography by the same radiologist. Additional voiding cystourethrography and scintigraphy was done according to the clinical algorithm. RESULTS: Prenatal and postnatal APRPD in patients with transient dilation were significantly lower than in those with urinary tract anomalies (UTA). On follow up, the slope of decrease in APRPD was significantly higher in transient dilation compared with UTA. APRPD 10 mm at first-month ultrasonography, predicted UTA with a sensitivity of 83.1%, and specificity of 71.1%. On multivariate analysis the likelihood of surgical intervention and final diagnosis were predicted independently by the UTD system risk group. CONCLUSIONS: Careful ultrasonography evaluation can avoid unnecessary testing in patients with transient or clinically insignificant dilation. The UTD classification system is valid for evaluation of postnatal hydronephrosis and is reliable in predicting the need for surgical intervention.

Multiple variations of collateral branches of the abdominal aorta associated with pyelic duplication: A case report.

PURPOSE: We describe a rare case of anatomical variation of the collaterals of the abdominal aorta associated with a duplication of the pyelic. MATERIAL AND METHOD: A 51-year-old patient in whom an abdominal CT scan was performed as part of the exploration of a cystic left renal mass objectified on ultrasound. RESULTS: A celiomesenteric trunk with two left renal arteries and a duplication of the left pyelon were found. CONCLUSION: The reported case is of interest in the rare association of these anatomical variants.

Pediatric Partial Nephrectomy for Upper Urinary Tract Duplication Anomalies: A Comparison Between Different Surgical Approaches and Techniques.

OBJECTIVE: To review and compare 4 different surgical approaches for partial nephrectomy of a nonfunctioning moiety in children with upper urinary tract duplication anomalies. MATERIALS AND METHODS: A retrospective review of all pediatric patients who underwent open partial nephrectomy (OPN), laparoscopic partial nephrectomy (LPN), robotic partial nephrectomy (RPN), or laparoendoscopic single site partial nephrectomy (LESS-PN) for the treatment of a nonfunctioning moiety in a duplicated collecting system at 2 medical centers between 2007 and 2017. Patient demographics, perioperative data, surgical techniques, complications, and results were compared. RESULTS: A total of 59 pediatric patients underwent partial nephrectomy for an upper urinary tract duplication anomaly during a 10-year period: 24 OPN, 7 LPN, 18 RPN, and 10 LESS-PN. Median age was 16 months (interquartile range 9-49.7). Median weight was 10.7 Kg (interquartile range 8.8-16.4). Median estimated blood loss was comparable between all minimally invasive approaches, but significantly increased in the open approach. OPN required more narcotics (0.554 mg Morphine equivalent/Kg/day, range 0.03-6.13) and Acetaminophen (72.12 mg/Kg/day, range 0-209.06) than all other groups in the study. Median operating time in OPN (154.5 minutes, range 108-413) and LESS-PN (140 minutes, range 65-245) were found to be significantly shorter in comparison to LPN (190 minutes, range 159-355), and RPN (256 minutes, range 163-458); (P = .03, .005, .02, and .005). CONCLUSION: Minimally invasive approaches (LPN, RPN, and LESS-PN) for partial nephrectomy in upper urinary tract duplication anomalies may be associated with decreased postoperative analgesia requirements, shorter hospital stay, less blood loss, and less use of drains in comparison to the open approach, while demonstrating efficacy and safety.

A modification with threading cannula needle-assisted 4-point suspension fixation for retroperitoneal laparoscopic pyeloplasty in children with ureteropelvic junction obstruction: a cohort study in single center.

PURPOSE: To evaluate the effect and safety of modifying a threading cannula needle-assisted suspension fixation in retroperitoneal laparoscopic dismembered pyeloplasty (LDP) for children with congenital ureteropelvic junction obstruction (UPJO). METHODS: Between December 2012 and December 2017, 45 children (< 14 years of age) with congenital UPJO were divided into two groups. In Group A, children underwent conventional "no-suspension fixation" LDP; and in Group B, "4-point suspension fixation" LDP was performed to lower difficulties and shorten operative time. The perioperative clinical data were recorded and analyzed. RESULTS: No statistical difference was found between two groups in preoperative characteristics. The duration of surgery, operative time for completion of anastomosis and the length of postoperative hospital stay in Group B was remarkably shortened than that in Group A, respectively (P < 0.05 for all). There was no significant difference between two groups in terms of postoperative renal pelvic diameter (RPD) decreasing, extubation time and success rates of surgery (P > 0.05 for all). In addition, no recurrent stenosis and urine leakage in both groups, and the postoperative RPD remained at the low level in both groups during the period of follow-up. CONCLUSIONS: Our modification of the 4-point suspension fixation for retroperitoneal LDP is an effective and safe method for children with UPJO. It can simplify the surgical procedures, lower difficulties (especially in precise anastomotic suturing) and shorten the learning curve. This modification might be of particular interest to urologists for improving treatment of children with UPJO.