Further experience with the vascular hitch (laparoscopic transposition of lower pole crossing vessels): an alternate treatment for pediatric ureterovascular ureteropelvic junction obstruction

Our experience of operated pediatric ureteropelvic junction obstruction patients

AIMS

Ureteropelvic junction obstruction (UPJO) may originate from extrinsic or intrinsic causes in children. The aim of this study is to present preoperative and postoperative data of our patients operated for UPJO.

METHODS

A total of 64 patients who underwent open pyeloplasty were investigated retrospectively. They were evaluated in terms of demographically, clinics, hydronephrosis, differential renal functions (DRFs), half-time tracer clearance (½TC), and histopathologic results. Patients' numerical results were stated as mean ± standard deviation (SD).

RESULTS

Male gender was more prevalent (n = 47, 73.4%) and mean age at surgery was 46.87 months. UPJO was located at the left side in 56.3% (n = 36), and at the right side in 39.1% (n = 25) of patients. It was bilateral in 4.7% (n = 3). Hydronephrosis was found antenatally in 68.8% (n = 44) of patients. The mean preoperative DRF was 49.7% (21-78%) and mean postoperative DRF was 49.2% (20-56%). Mean renal scintigraphic t1/2 was >20 min for all patients. The mean AP diameter was 21.58 mm (10-62 mm). Muscular hypertrophy was the most common pathological finding, mean length of excised segment was 10.26 mm (3-40 mm). Crossing vessel (CV) was detected in 17.18% (n = 11). The CV was statistically associated with increased age of operation, left side, and female gender. Statistically significant hydronephrosis was found in non-CV patients. Re-operation was required in seven patients (7.8%).

CONCLUSIONS

Intrinsic pathologies are more seen in the etiology of UPJO patients with antenatal diagnosis and this group needs operation at an earlier age. However, CV is found more commonly in patients who are diagnosed and operated at older ages.

Association between intraoperative anatomical variation and histopathological parameters in cases of ureteropelvic junction obstruction in children: A cross-sectional study

Introduction

The intraoperative anatomical findings (IOAF) of all ureteropelvic junction obstruction (UPJO) cases are not identical. Moreover, there is also controversy in the literature regarding histopathological (HP) findings in cases of UPJO. In the present study, we evaluated different IOAF and assessed their association with specific HP parameters.

Materials and Methods

This was a cross-sectional study set-up, which was carried out in a tertiary care centre. Children with UPJO who underwent surgery between 2017 and 2020 were enrolled. The following IOAF were noted: Type of pelvis (extrarenal or intrarenal), insertion of the ureter (high or normal), presence of lower pole crossing vessel (CV), negotiation of UPJ segment with double J stent (3 Fr) and length of internal narrowing (LIN) at UPJ. The resected segment of UPJ was assessed at three levels (pelvis, UPJ and ureter) for various HP parameters including fibrosis, oedema, inflammation and smooth muscle hypertrophy (SMH).

Results

Thirty-nine children were included in the study with a mean age of 31 months. The summary statistics of IOAF were intrarenal pelvis in 5 cases, high insertion of the ureter (HIU) in 9, CV in 6, negotiable UPJ in 23, and 16 cases showed LIN >1 cm. All cases showed SMH at the pelvis region and SMH with fibrosis at the UPJ region. At the pelvis region, there was an association between (1) HIU with oedema and chronic inflammation (CIF), (2) CV with CIF and (3) LIN with CIF and SMH. At the UPJ region, there was an association between (1) CV and negotiable UPJ with less fibrosis and (2) LIN with SMH. At the ureteric end, CV showed an association with less fibrosis and more CIF.

Conclusion

All UPJO cases have some common HP findings. Although, some particular IOAF, i.e., presence of CV, negotiable UPJ, HIU and LIN showed association with specific HP parameters.

Ureteropelvic junction obstruction in children by polar vessels: histological examination result

In children, ureteropelvic junction obstruction (UPJO) is mostly caused by intrinsic factors (IUPJO) such as abnormal amounts of muscle and collagen deposition; extrinsic UPJO are rare and often due to crossing vessels (CVs). What is not clear is whether there is also intrinsic UPJ pathology in patients with CV. The aim of our study was to compare the histology of the two types of obstruction and to determine whether these histologic features are distinguishable enough to enable to identify the cause of obstruction based on histologic appearance alone. We retrospectively reviewed pathology reports of 38 children with UPJO that underwent surgery in our hospital from 2008 to 2022. The intrinsic and extrinsic groups consisted of 18 and 20 patients, respectively. After ematoxylin-eosin and Gomori's trichrome staining the specimens were scored for fibrosis and muscular hypertrophy in histhopatology, and CD117 antibody were used to detect interstitial Cajal-like cells. In our study, histological analyses revealed no differences between the CV and IUPJO specimens in terms of presence and degree of fibrosis and muscular hypertrophy; likewise, for presence of interstitial Cajal-like cells.

Retroperitoneoscopy-Assisted Dismembered Pyeloplasty With Single-Site Plus One Port in Older Children With Congenital Hydronephrosis

INTRODUCTION

This study aimed to clarify the advantage of retroperitoneoscopy-assisted dismembered pyeloplasty with single-site plus one port (RPSPO) for pediatric congenital hydronephrosis in patients aged ≥7 years.

METHODS

We retrospectively compared a group of patients aged ≥7 years (study group) with patients aged <7 years (comparison group), who underwent RPSPO between August 2015 and August 2018, in terms of preoperative patient characteristics, intra- and perioperative results, and postoperative results.

RESULTS

The study group consisted of eight patients. The median body weight at surgery was 27 kg (20-38 kg). The median age at surgery was 102.5 m (87-139 m). The severity of hydronephrosis on the affected side graded by the Society for Fetal Urology grade was grade 3 in one case and grade 2 or less in all other cases. All patients underwent a ^99m Tc-MAG3 renogram. Comparison between the two groups showed significant differences in body weight at surgery (p = 0.003), age (p < 0.001), and preoperative hydronephrosis grade (p = 0.007), but the median length of the skin incision was 20 mm in both groups, with no significant difference (p = 1.000). Redo pyeloplasty was not required in any patient in either group.

CONCLUSION

RPSPO is an advantageous procedure for older children because it allows precise ureteropelvic neoanastomosis under direct vision and the same wound size as in younger children.

Minimally invasive vascular hitch to treat pediatric extrinsic ureteropelvic junction obstruction by crossing polar vessels: A systematic review and meta-analysis

INTRODUCTION

Vascular hitch (VH) gained an increasing success in treating ureteropelvic junction obstruction (UPJO) by crossing vessels (CV) in pediatrics.

AIMS OF THE STUDY

We aimed: (i) to compare laparoscopic VH versus laparoscopic dismembered pyeloplasty (DP) to treat UPJO by CV; (ii) to review possible amelioration given by a robot-assisted procedure.

METHODS

Using defined search strategy, three investigators identified all studies on laparoscopic VH. Those studies comparing VH versus DP or versus robot-assisted VH were included in the meta-analysis. The meta-analysis was conducted using RevMan 5.3. Data are mean ± SD.

RESULTS

Systematic review - Of 2783 titles/abstracts screened, 43 full-text articles were analyzed. Twelve studies on laparoscopic VH (298 pts) reported 98.3% success rate, with 1.3% intra-operative complications. Meta-Analysis - Five studies compared laparoscopic VH versus laparoscopic DP (277 pts). Operative time was reduced in VH (102.5 ± 47.5min) compared to DP (165.7 ± 53.7min; p < 0.00001). Complications were similar (VH 4/119 pts, 3.4 ± 1.2% versus DP 15/158 pts, 9.5 ± 6.8%; p = ns). Hospital stay was shortened in VH (1.1 ± 0.9dd) versus DP (3.3 ± 3.2dd; p < 0.0001; Summary Figure). The success rate was comparable (VH 115/118 pts, 97.5 ± 1.6% versus DP 157/158 pts, 99.4 ± 0.5%; p = ns). Two prospective studies compared robot-assisted VH to laparoscopic VH (53 pts). No differences were found among complications (robot-assisted VH 0/13 pts, 0% versus laparoscopic VH 1/40 pts, 2.5%; p = ns) and success rate (robot-assisted VH 13/13 pts, 100% versus laparoscopic VH 39/40 pts, 97.5%; p = ns).

DISCUSSION

Several studies have been reported long-term results of laparoscopic VH in children. However, few papers demonstrated its superiority over laparoscopic DP to treat extrinsic UPJO. In the present study, we found similar incidence of complications and success rates when comparing VH versus DP. Nonetheless, the operative time and the length of hospital stay were significantly reduced in VH compared to DP. An increasing number of surgeons performed robotic-assisted VH, reporting promising outcomes. However, only a couple of studies compared robot-assisted VH to laparoscopic VH, with a similar incidence of complications and success rate in both procedures. The main limitations of the study were related to the slight number of papers included and to their quality, since all of them were retrospective studies or prospectively followed-up cohort of patients.

CONCLUSIONS

Laparoscopic VH seems to be a safe and reliable procedure to treat UPJO by CV. The procedure appeared quicker than laparoscopic DP, with shortened hospital stay. Further studies are needed to corroborate these results and to establish amelioration given by a robot-assisted procedure.

Laparoscopic Vascular Hitch for Polar Vessels in Pyeloureteric Junction Obstruction: Medium-Term Follow-up of a Monocentric Experience

INTRODUCTION

 To evaluate medium-term results of the management of patients with pyeloureteric junction obstruction (PUJO) secondary to lower pole vessels managed by a laparoscopic vascular hitch technique.

MATERIALS AND METHODS

 We performed a retrospective monocentric study of all patients who were operated using this technique, transperitoneal laparoscopy (TL) or robotic surgery (RS), from 2011 to 2018. Description of the initial population, pre- and postoperative data was collected and analyzed.

RESULTS

 During the study period, 25 patients (11 males and 14 females) with a mean age of 11.1 years were managed. Initial symptoms leading to the diagnosis were present in 21 children (lumbar pain 17, high blood pressure 1, and infection 3). Four patients were diagnosed incidentally (three) or following a prenatal screening (one). The diagnostic has been confirmed in all patients by ultrasound scan completed by computed tomography or magnetic resonance imaging scans. Twenty-one patients were operated by TL and four by RS. Mean operating time was 90.2 minutes. Three immediate postoperative complications were noticed including one urinary tract infection, one urinary tract rupture, and one postoperative massive dilatation. After a mean follow-up of 3 1.5 years, 17 patients remain asymptomatic. Mean pelvic diameter was preoperatively 35 mm and postoperatively 10.5 mm (p < 0.005). Of the eight remaining patients, six required reoperation (pyeloplasty) and two remained symptomatic with recurrent flank pain.

CONCLUSION

 In our experience, PUJO managed by the vascular hitch technique is associated with a 68% success rate after a 3-year follow-up. These results are different from the current literature which reported success rate of 96% after 52 months. It leads us to question the efficiency of this technique in the long term in our hands both concerning the indications and the surgical procedure itself. Further studies are required to collect data concerning the evolution of our patients during adulthood to compare their evolution to classic pyeloplasty.

Vascular hitch for paediatric pelvi-ureteric junction obstruction with crossing vessels: institutional analysis and systematic review with meta-analysis

OBJECTIVE

To compare the outcomes for laparoscopic vascular hitch (VH) and dismembered pyeloplasty in patients with pelvi-ureteric junction obstruction (PUJO) secondary to crossing vessels (CV).

PATIENTS AND METHODS

Patients who underwent laparoscopic management of CV at our institution were identified between 2008 and 2020. Baseline characteristics and outcome measures were compared between those who underwent VH and those who underwent dismembered pyeloplasty. Those who underwent VH were selected intraoperatively by identifying CV in the absence of intrinsic obstruction by assessing resolution of hydronephrosis after cranially displacing the CV away from the PUJ, followed by intraoperative fluid bolus and diuretic test. In addition, a systematic search and meta-analysis were performed in June 2020 (International Prospective Register of Systematic Reviews [PROSPERO] ID CRD42020195833).

RESULTS

A total of 20 patients underwent VH and 74 dismembered pyeloplasty. On multivariate analysis, VH was associated with: shorter operative time (P = 0.001; odds ratio [OR] 0.455, 95% confidence interval [CI] 0.294-0.705) and length of stay (P = 0.012; OR 0.383, 95% CI 0.183-0.803), lower use of stents (P < 0.001; OR 0.024, 95% CI 0.004-0.141) and opioid administration (P = 0.005; OR 0.157, 95% CI 0.044-0.567). From our literature search, 194 records were identified and 18 records were included (three comparative and 16 non-comparative). Meta-analysis of the comparative studies and our institutional data showed similar success rates (relative risk [RR] 1.77, 95% CI 0.33-9.52) and complication rates (RR 0.75, 95% CI 0.20-2.82). VH was associated with shorter operative time (standardised mean difference [SMD] -1.65, 95% CI -2.58 to -0.72 h) and hospital stay (SMD -1.41, 95% CI -2.36 to -0.47 days). The VH success rates ranged from 87.5% to 100% in the identified studies. Failure of VH was associated with unrecognised concomitant intrinsic obstruction in addition to CV.

CONCLUSIONS

A VH, for well-selected patients with CV without concomitant intrinsic obstruction, offers a high success rate with shorter operative times.

Minimally Invasive Treatment of Pediatric Extrinsic Ureteropelvic Junction Obstruction by Crossing Polar Vessels: Is Vascular Hitching a Definitive Solution? Report of a Multicenter Survey

BACKGROUND

This article aimed to evaluate the outcome of laparoscopic vascular hitch (VH) as an effective alternative to dismembered pyeloplasty in the treatment of children with extrinsic ureteropelvic junction obstruction (UPJO) by crossing vessels (CVs), by reporting the experience of three Italian centers of Pediatric Surgery.

METHODS

From 2006 to 2014, 54 children (18 girls and 36 boys, average age 10.7 years) affected by suspected extrinsic UPJO by CV were treated in three different institutions: 51 patients underwent laparoscopic VH, while 3 patients, in which a coexisting intrinsic etiology of UPJO was doubtful, underwent laparoscopic dismembered pyeloplasty. Preoperative diagnostic workup included: ultrasound (US)/Doppler scan, mercaptoacetyltriglycine (MAG3)-renal scan, and functional-magnetic-resonance-urography (fMRU). Symptoms at presentation were recurrent abdominal/flank pain and hematuria. All patients presented intermittent hydronephrosis (range 18-100 mm) on US and an obstructive pattern on MAG3 renogram.

RESULTS

Average operative time was 108 minutes, and average hospital stay was 1.8 days. As for complications, we reported a small abdominal wall hematoma and a high UPJ distortion without obstruction in 2 patients, not requiring reintervention (grade I Clavien-Dindo). At follow-up (range 12-96 months), all patients reported resolution of symptoms, decrease in the hydronephrosis grade, and improved drainage on MAG3 renogram.

CONCLUSIONS

Our results demonstrated the safety and efficacy of laparoscopic VH for treatment of extrinsic UPJO by CV, registering excellent outcomes in a very selected patient population. The careful selection of patients through intraoperative assessment of anatomical and functional aspects is a crucial step to confirm indications for VH and maintain a high success rate with the procedure. We believe that any concerns regarding the coexistence of intrinsic stenosis should certainly lead to opening the collecting system and to performing a classic dismembered pyeloplasty.

Laparoscopic transposition of lower pole crossing vessels (vascular hitch) in children with pelviureteric junction obstruction

BACKGROUND

Congenital hydronephrosis due to intrinsic or extrinsic uretero-pelvic-junction (UPJ) obstruction (UPJO) is a common problem in childhood UPJO may be caused by intrinsic disorganization or by extrinsic compression from crossing vessels (CV); extrinsic causes usually present symptomatically in older children. This report the large Italian experience in the treatment of children with extrinsic-UPJO by CV.

METHODS

We analyzed the data of 51 children (17 girls and 34 boys, median age 10, 7 years) affected by extrinsic-UPJO were treated in three Italian institutions with laparoscopic transposition of CV (Hellström Vascular Hitch modified by Chapman).The intraoperative diuretic-test was performed in all patients before and after the vessels transpositions confirming the extrinsic-UPJO. We included in the study only patients with suspicion of vascular extrinsic obstruction of the UPJ. Symptoms at presentation were recurrent abdominal/flank pain and haematuria. All patients presented intermittent ultrasound (US) detection of hydronephrosis (range, 18-100 mm). Preoperative diagnostic studies included: US/doppler scan, MAG3-renogram, functional-magnetic-resonance-urography (fMRU).

RESULTS

Median operative time was 108 minutes; median hospital stay: 3, 4 days. Unique complications: a small abdominal wall hematoma and higher junction-translocation without obstruction. During follow-up (range, 12-96 months) all patients reported resolution of their symptoms, a decrease in the hydronephrosis grade and improved drainage on diuretic renogram.

CONCLUSIONS

We believe that Vascular Hitch is less technically demanding than laparoscopic pyeloplasty, resulting in a lower complication rate and a significantly reduced hospitalization. The results of our study allow us to conclude that laparoscopic VH may be a safe, feasible, and attractive alternative to treat obstructed hydronephrosis due to CV presenting a useful alternative to AHDP in the management of symptomatic children where CV are deemed the sole aetiology. We recommend careful patient selection based on preoperative clinical and radiologic findings that are diagnostic of extrinsic-UPJO, combined with intraoperative-DT to confirm the appropriate selection of corrective procedure.

Intraoperative inspection of the ureteropelvic junction during pyeloplasty is not sufficient to distinguish between extrinsic and intrinsic causes of obstruction: Correlation with histological analysis

INTRODUCTION

Based on current knowledge, it is possible to have an initial diagnosis of intrinsic or extrinsic ureteropelvic junction obstruction (UPJO) based solely on clinical and imaging findings. However, it may not be possible to strictly discriminate an intrinsic case with an additional extrinsic component from a primarily intrinsic stenosis because of lower pole aberrant vessels. These two disorders may coexist or trigger each other. Herein, we aimed to compare the histological changes observed in intrinsic and extrinsic types of UPJO. Our hypothesis is that inspecting the UPJ during pyeloplasty may not be a sufficient way to delineate the underlying cause of obstruction in every individual.

MATERIAL AND METHODS

We retrospectively reviewed the data of 56 patients who had dismembered pyeloplasty. The intrinsic and extrinsic groups consisted of 38 and 18 patients, respectively. Masson's trichrome stain, CD117, and connexin 43 (Cx43) antibody were used in histopathology and immunochemistry. Statistical calculations were done with chi-square and Mann-Whitney U tests.

DISCUSSION

Connexin 43 staining pattern, CD117 positive cell count, and the extent of fibrosis did not differ significantly between extrinsic and intrinsic cases. However, the difference with regard to the degree of muscular hypertrophy was close to statistical significance. The exact pathophysiological mechanism underlying UPJO has yet to be elucidated. A study directly comparing both groups histologically is indeed rare. Our study showed that there are no significant differences between the intrinsic and extrinsic groups in terms of the pacemaker activity, gap junctional communication, and extent of fibrosis. Muscular hypertrophy, which was marginally higher in our extrinsic group, may persist despite successful relocation of the obstructing vessel. The main drawbacks of our study are; the absence of a control group and the retrospective study design with its inherent selection biases.

CONCLUSIONS

Immunohistochemical profiles of intrinsic and extrinsic UPJOs resemble each other. Intraoperative inspection of the UPJ may not be enough for accurate discrimination for a surgical procedure that can correct only the extrinsic cause.

Laparoscopic transposition of lower-pole crossing vessels: Long-term follow-up of 33 patients at puberty

PURPOSE

Laparoscopic transposition of lower-pole crossing vessels (LPCV) has been described as an effective alternative to dismembered pyeloplasty in selected indications of hydronephrosis, with purely extrinsic vascular PUJ obstruction. We hypothesized that the initial good results of laparoscopic transposition of LPCV in children presenting with pure extrinsic PUJO were sustained at puberty when these children go through statural growth, without inducing significant changes in systemic arterial blood pressure. Hence, we analysed the long-term follow-up of adolescents successfully treated with this technique during childhood, reviewed after they have reached puberty, focusing on the incidence of recurrent symptoms, renal dilatation, and systemic hypertension.

PATIENTS AND METHODS

Early 2015, among a cohort of 70 patients prospectively followed-up since they had undergone laparoscopic transposition of LPCV during childhood (2005-2012), we performed systematic clinical assessment of the 33 adolescent patients (16 years; range 12-22) who had reached puberty age. Assessment focused on clinical examination, arterial blood pressure measurements, and renal ultrasonography (Table).

RESULTS

The median delay since surgery was 67 months (31-113 months). Arterial blood pressure adjusted for age and height was within normal range in all patients. Three patients had occasional episodes of abdominal pain: two of them had normal US (including during pain episodes), one had persistent extra-renal dilated pelvis with no calyceal dilatation. None of them showed obvious clinical characteristics linking the pain to a renal origin. Renal US showed residual SFU grade 2 pelvicalyceal dilatation in 2/33 asymptomatic patients; SFU grade 1 extra-renal pelvis dilatation in 3, and was normal in the remaining. When Doppler analysis was performed, there was no evidence of lower-pole parenchyma perfusion defect.

DISCUSSION

In adolescents successfully treated during childhood with transposition of LPCV, there seemed to be no impact of this procedure on systemic arterial blood pressure in adolescents after puberty, nor any evidence of late recurrence of symptoms or hydronephrosis. The main limitation of the present study relies in its retrospective nature, the limited sample size, and the obvious difficulty in adequate selection of candidate patients to this technique. The present experience however reinforces the hypothesis that a vast majority of children can be definitely cured with transposition of LPCV when they represent the sole aetiology of obstruction.

CONCLUSION

In the long-term follow-up, most adolescents successfully treated during childhood by laparoscopic transposition of LCPV for PUJ extrinsic obstruction remain asymptomatic, with normal arterial blood pressure, and normal renal ultrasound when they reach puberty.

Ureteropelvic junction obstruction in children by polar vessels. Is laparoscopic vascular hitching procedure a good solution? Single center experience on 35 consecutive patients

PURPOSE

We report the results of laparoscopic vascular hitching (LVH) in a series of children with ureteropelvic junction obstruction (UPJO) owing to aberrant lower polar crossing vessels (CV). Our aim is to confirm if LVH associated with intraoperative diuretic test (DT) represents a good procedure to treat extrinsic-UPJO by CV. In order to confirm the relief of the obstruction we suggest performing an intraoperative DT.

MATERIALS AND METHODS

In our department from 2006 to 2014, 120 patients were treated for both extrinsic and intrinsic-UPJO. 85 (30 females, 55 males) presented an intrinsic obstruction and underwent dismembered pyeloplasty (AHDP), 61 open, 16 laparoscopic, 8 retroperitoneoscopic. 35 (23 males, 12 females) were studied for a suspected extrinsic-UPJO: 30 were treated with LVH (modified Hellström vascular hitch). Intraoperative-DT was performed in all patients before and after vessel transpositions confirming the UPJO and eventual relief after the procedure. We included in the study only patients with suspicion of vascular extrinsic-UPJO. Average age at surgery was 7.5years. Symptoms of presentation were recurrent abdominal/flank pain and hematuria. All patients presented ultrasound (US) detection of hydronephrosis. Preoperative diagnostic studies include: US/doppler scan, MAG3 renogram, urography, functional magnetic resonance urography (fMRU) and CT scan.

RESULTS

28 out 35 patients had a correct preoperative diagnosis, and the remaining needed an intraoperative diagnosis confirmation. All 35 patients had an intraoperative-DT: 30 patients underwent LVH (positive-DT); 3 patients (negative-DT) underwent laparoscopic-AHDP for intrinsic-UPJO; two with positive-DT and nonobstructive CV, had no surgical treatment. Median operating time was 95min; mean hospital stay was 4days. At 12-84months follow-up 29 patients remained symptoms-free, one needed after two years a laparoscopic-AHDP.

CONCLUSIONS

According our experience, LVH associated with intraoperative-DT may be considered a safe procedure to treat extrinsic-UPJO by CV in carefully selected patients. In particular, the very low incidence of relapse suggest that in suspicion of extrinsic-UPJO, performing intraoperative-DT after CV transposition allows to exclude intrinsic-UPJO confirming that the LVH-procedure has relieved the pelvic obstruction, precluding the need for AHDP.

Long-term results with the laparoscopic transposition of renal lower pole crossing vessels

BACKGROUND

For the treatment of ureterovascular pelviureteric junction obstruction (PUJO), transposition of lower pole crossing vessels (LPCV) has been described as an alternative to dismembered pyeloplasty.

PURPOSE

To report on the long-term follow-up of children after laparoscopic transposition of LPCV.

METHODS

A retrospective analysis of 70 children consecutively treated by laparoscopic transposition of LPCV. Candidate patients were selected on the basis of clinical history, renal ultrasound (US), and pre-operative mercaptoacetyltriglycine (MAG-3) scan. Selection criteria included: presence of LPCV with SFU Grade 1-2 hydronephrosis, impaired drainage on MAG-3 and intraoperative normal pelviureteric junction (PUJ) and ureter peristalsis. Thinned parenchyma, impaired renal function, or history of prenatal hydronephrosis were not considered as exclusion criteria. Children were clinically followed up with US and MAG-3 scan. Success was defined by symptom resolution with improvement in hydronephrosis.

RESULTS

Seventy children, aged 8.3 years (range 2.75-16.0), were selected. Procedures were performed through transperitoneal laparoscopy (n = 42) or were robotic-assisted (n = 28). Operative time was 120 min and length of hospital stay was 2 days. The outcome was successful in 67/70 patients (96%), with a median follow-up of 52 months (range 13-114). There were three failures in children who eventually underwent dismembered pyeloplasty for a symptomatic, undiagnosed, intrinsic PUJ obstruction. Two of them had been postnatally followed for a resolving prenatally diagnosed hydronephrosis. Three children became free of symptoms, had improved hydronephrosis, but still showed impaired drainage on MAG-3 and are being closely followed up.

DISCUSSION

Although this procedure proves to have long-term efficiency in selected indications, the main challenge is to intraoperatively ascertain the absence of associated intrinsic stenosis. Objective criteria remain difficult to establish, but intraoperative findings, including dependent, funnel-shaped, normal-looking PUJ with decreasing hydronephrosis after pelvis and LPCV mobilisation, and efficient peristalsis across the PUJ under intraoperative diuretic test, represent a low likelihood of associated intrinsic stenosis. Ipsilateral impaired renal function doesn't seem to be associated with an adverse outcome. In contrast, a prenatal history of mild or self-resolving hydronephrosis in a patient later presenting with intermittent dilatation, raises the suspicion of associated intrinsic PUJ obstruction, as it is associated with a higher risk of failure.

CONCLUSION

With a long postoperative follow-up, the robotic-assisted or laparoscopic vascular hitch procedure has been successful in treating a selected group of children with obstructive LPCV, and represents a safe and reliable alternative to standard dismembered pyeloplasty in the absence of intrinsic PUJO suspected on prenatal US.

Differences between intrinsic and extrinsic ureteropelvic junction obstruction related to crossing vessels: histology and functional analyses

PURPOSE

In children, ureteropelvic junction obstruction (UPJO) is mostly caused by intrinsic factors (IUPJO); extrinsic UPJO are rare and often due to crossing vessels (CVs).

METHODS

We retrospectively reviewed all data of children with UPJO that underwent surgery in our institution from 2004 to 2011. Analyses included age at surgery, gender, preoperative and postoperative results of ultrasound and renal scans [differential renal function (DRF); signs of obstruction], and pathology reports. Available histological specimens of cases with CV were compared to a random selection of intrinsic cases in a blinded fashion. After additional Masson's trichrome staining, the specimens were scored for fibrosis, muscular hypertrophy, and chronic inflammation.

RESULTS

Out of 139 patients with UPJO, 39 cases were associated with CV. Median age at surgery was 68 months (range 2-194) in the CV group and 11.5 months (range 0-188) in IUPJO group. Laparoscopic dismembered pyeloplasty (LDMP) was carried out in 134 and open DMP in five patients. Preoperative ultrasound identified 28/39 cases with CV. DRF below 40 % was more frequently seen in CV patients (p = 0.020). Histological analyses revealed no differences between the CV and IUPJO specimens in total. CV patients with higher grades of muscular hypertrophy had lower preoperative DRF, compared to those with higher preoperative DRF (p = 0.026). Functional recovery after (L)DMP was excellent in both groups.

CONCLUSION

We could not find any significant histological differences between CV and IUPJO in children. To obtain excellent functional recovery, surgical procedures with a definite correction of the UPJ should be preferred in paediatric patients with CV.

Hydronephrosis: Comparison of extrinsic vessel versus intrinsic ureteropelvic junction obstruction groups and a plea against the vascular hitch procedure

INTRODUCTION

Pediatric ureteropelvic junction obstruction (UPJO) due to an extrinsic crossing vessel (CV) is rare and often remains undiagnosed preoperatively. Vascular hitch procedures are often performed as associated intrinsic obstruction is not expected. We compared data and intravenous urography (IVU) findings of patients with aberrant CV versus those with intrinsic UPJO, all undergoing open dismembered pyeloplasty.

PRIMARY OBJECTIVE

Is accurate pre-operative diagnosis of aberrant CV causing extrinsic UPJO possible?

SECONDARY OBJECTIVE

To assess differences in the demographic, clinical, radiological, intra-operative features and postoperative improvement after pyeloplasty between patients with a CV and those with only intrinsic UPJO.

PATIENTS AND METHODS

Prospective study of all children below 12 years with UPJO presenting to a tertiary referral centre and who underwent open Anderson - Hynes dismembered pyeloplasty between 2003 and 2013 was conducted. Pre-operative investigations included serial ultrasonography, renal dynamic [ethylene di-cysteine (EC)] scan and IVU. These were repeated 3 months after pyeloplasty. Pre-operative IVUs of children with CV were compared with the IVUs of an equal number of similar aged children, randomly selected from the intrinsic obstruction group.

RESULTS

Pyeloplasty was performed in 643 children during the study period. Data of 33 children with aberrant CVs (mean age 6.99 years) were compared with the remaining 610 children (mean age 3.27 years) with only intrinsic obstruction. Highly significant associations of those with CV included age above 2 years, female gender, associated anomalies, abdominal pain in those above 2 years and poor preoperative function on IVU. Specific IVU features which were statistically highly significant in favor of presence of CV were small, intrarenal and globular flat bottomed pelvis. (Figure) Calyceal dilatation was also more prominent in the CV group. A funnel shaped, extrarenal pelvis was highly significant in favor of intrinsic obstruction. There was associated intrinsic obstruction in addition to CV obstruction in 8 children. All children symptomatically improved after pyeloplasty and did well on long term follow up. The majority showed improvement or stabilization of function on EC scan.

DISCUSSION

With the advent of antenatal ultrasonography, most children with UPJO are detected early. Children with CV tend to present later. This is often detected during surgery. Color Doppler is useful but is operator dependant and not performed routinely. In this study, IVU showed the presence of obstruction and loss of function unlike color Doppler, but also revealed specific diagnostic features not previously reported in literature. This can help in accurate preoperative prediction and avoid endopyelotomy, or a dorsal lumbotomy/retroperitoneal approach. Renal function in CVs is expected to be good as the obstruction is thought to be intermittent. However, we noted delayed contrast uptake on IVU in 60.6% and differential renal function on EC scan below 40% in 17 patients (56.6%). These indicate the effect of the obstruction on the renal parenchyma and the importance of early detection. Higher association with other anomalies and higher incidence in females has also not been emphasized in the literature so far. We noted associated intrinsic obstruction in 24.24% patients which is highly significant. This category of patients is likely to be missed and inappropriately treated if a "vascular hitch procedure" is performed. None of our patients had postoperative complications.

CONCLUSIONS

Characteristic features were seen on IVU helping in preoperative diagnosis which can be extrapolated to magnetic resonance urography. There is a higher association of CV in age above 2 years, females, associated congenital anomalies, delayed uptake on IVU and differential renal function below 40% compared to intrinsic obstruction. Associated intrinsic obstruction in 24% with no postoperative complications indicates the superiority of dismembered pyeloplasty over vasculopexy procedures.

Lower pole vessels in children with pelviureteric junction obstruction: laparoscopic vascular hitch or dismembered pyeloplasty?

OBJECTIVE

To choose between laparoscopic "vascular hitch" (VH) and dismembered pyeloplasty (DP) in treatment of aberrant lower pole crossing vessels potentially responsible for pelviureteric junction obstruction (PUJO) in older children.

PATIENTS AND METHODS

Retrospective study of 19 patients treated laparoscopically for PUJO. Based on videos of the procedures, we studied the anatomical relationship between the renal pelvis, the pelviureteric junction, and the aberrant vessels.

RESULTS

Eight patients had laparoscopic VH and 11 had DP. All patients with DP needed drainage. In the VH group, 7/8 patients were asymptomatic and had decreased pelvic dilation. Half of them accepted MAG3 scintigraphy, and in these patients the obstructive syndrome disappeared completely. The last patient in this group was lost to follow-up. We observed three anatomical variations in the location of polar vessels: type 1 (in front of the dilated pelvis), type 2 (in front of the pelviureteric junction), type 3 (under the pelviureteric junction, resulting in ureteral kinking).

CONCLUSION

Laparoscopic VH is a simple technique involving no urinary anastomosis or drainage, but we cannot guarantee that the crossing vessels are the sole etiology for PUJO. Following our experience, only patients with type 3 anatomical variations and with a normal pelviureteric junction should be proposed for VH.

Robot-assisted and laparoscopic repair of ureteropelvic junction obstruction: a systematic review and meta-analysis

CONTEXT

Over the last two decades, minimally invasive treatment options for ureteropelvic junction obstruction (UPJO) have been developed and popularized.

OBJECTIVE

To critically analyze the current status of laparoscopic and robotic repair of UPJO.

EVIDENCE ACQUISITION

A systematic literature review was performed in November 2012 using PubMed. Article selection proceeded according to the search strategy based on Preferred Reporting Items for Systematic Reviews and Meta-analyses criteria.

EVIDENCE SYNTHESIS

Multiple series of laparoscopic pyeloplasty have demonstrated high success rates and low perioperative morbidity in pediatric and adult populations, with both the transperitoneal and retroperitoneal approaches. Data on pediatric robot-assisted pyeloplasty are increasingly becoming available. A larger number of cases have also been reported for adult patients, confirming that robotic pyeloplasty represents a viable option for either primary or secondary repair. Robot-assisted redo pyeloplasty has been mostly described in the pediatric population. Different technical variations have been implemented with the aim of tailoring the procedure to each specific case. The type of stenting, retrograde versus antegrade, continues to be debated. Internal-external stenting as well as a stentless approach have been used, especially in the pediatric population. Comparative studies demonstrate similar success and complication rates between minimally invasive and open pyeloplasty in both the adult and pediatric setting. A clear advantage in terms of hospital stay for minimally invasive over open pyeloplasty was observed only in the adult population.

CONCLUSIONS

Laparoscopy represents an efficient and effective less invasive alternative to open pyeloplasty. Robotic pyeloplasty is likely to emerge as the new minimally invasive standard of care whenever robotic technology is available because its precise suturing and shorter learning curve represent unique attractive features. For both laparoscopy and robotics, the technique can be tailored to the specific case according to intraoperative findings and personal surgical experience.

Laparoscopic transperitoneal pyeloplasty in children from age of 3 years: our clinical outcomes compared with open surgery

OBJECTIVE

To report clinical outcomes for laparoscopic pyeloplasty (LP) in children compared with open pyeloplasty (OP) and literature findings.

PATIENTS AND METHODS

In a prospective study, the outcomes of 57 consecutive transperitoneal LP in children from the age of 3 years were analyzed and compared with a matched historic control group of OP and with series of LP in the literature. Successful result was defined as resolution of symptoms, no conversion or re-operation, improved hydronephrosis, and/or improved renographic drainage.

RESULTS

Mean operative time was 177 (SD 50.5)min in the LP group and 108 (SD 25.6)min in the OP group (p < 0.001). Mean hospital stay was 1.2 (SD 0.46) days in the LP and 6.7 (SD 1.2) days in the OP group. Improvement in renographic drainage was observed more often after LP than after OP (98% vs 83%; p = 0.010). A successful result was reported in 56 (98%) LP and 54 (95%) OP (p = 0.298) patients. Our LP series demonstrates a high success rate compared to literature data.

CONCLUSIONS

Our LP has a similar success rate and more often improved renographic drainage in comparison to OP. Furthermore, our LP demonstrates a shorter hospital stay and favorable outcomes compared to the literature. We thus regard LP as standard treatment for repair of ureteropelvic junction obstruction in children from the age of 3 years.

Laparoscopic bypass pyeloureterostomy

Minimally invasive surgery has been increasingly applied in paediatric urology, including the treatment of ureteropelvic junction obstruction. To the best of our knowledge, we describe the first laparoscopic bypass pyeloureterostomy in a 3-month-old male infant, with giant hydronephrosis and high insertion of the ureter into the renal pelvis.

Laparoscopic management of ureteropelvic junction obstruction by division of the aberrant vein and cephalad relocation of the crossing artery: a long-term follow-up of 42 cases

OBJECTIVE

It was intended to demonstrate the update report of our experience with laparoscopic management of ureteropelvic junction obstruction by division of the aberrant vein and cephalad relocation of the crossing artery in a large group of patients with long-term follow-up.

PATIENTS AND METHODS

Three hundred and twenty-nine patients were candidate to undergo laparoscopic transperitoneal ureteropelvic junction obstruction management from June 2001 to March 2009. Intraoperatively, lower pole crossing vessels were identified in 117 patients (35.5%). After division of the aberrant vein, the crossing artery was relocated cephalad and fixed to peripelvic tissue. Renal pelvic emptying with proper pyeloureteral peristalsis was considered in 71 patients, so neither pyeloplasty nor Double-J stent was fixed for them. Postoperative outcomes were assessed with intravenous urography and/or diethylene triamine pentaacetic acid-diuretic renal scan.

RESULTS

Of the 71 patients who underwent this laparoscopic approach, 42 were completely followed over a long-term period. The mean age of patients was 27 (7-69) years. The mean operative duration was 133 (55-185) minutes and blood loss was negligible. The mean hospital stay was 2.8 (1-7) days and mean follow-up was 29 (3-84) months. Overall success rate was 90% and recurrence of obstruction was noted in two patients. No significant complications were observed.

CONCLUSION

Cephalad relocation of the lower pole crossing artery after division of the crossing vein in selected cases could be an ideal alternative for dismembered pyeloplasty with noticeable outcomes in long-term follow-up.

Laparoscopic vascular relocation: alternative treatment for renovascular hydronephrosis in children

AIMS

The standard treatment for pelviureteric junction obstruction (PUJO) has been dismembered pyeloplasty. The open surgical, Hellström procedure in which crossing polar vessels are relocated, has been an option in adult urological practice. We present our experience with laparoscopic vascular relocation in children.

METHODS

Data were retrospectively gathered on all patients who underwent laparoscopic relocation of lower pole vessels (LRLPV) at our institution between July 2004 and March 2008. Follow-up ultrasounds and MAG3 were obtained.

RESULTS

LRLPV was performed in 10 boys and 9 girls. Patients were between 5.8 and 15.25 years (median 9.9 years). They presented with recurrent abdominal pain (n = 17), urinary tract infections (n = 7) and haematuria (n = 3). On ultrasound, MAG3 and retrograde studies they had hydronephrosis, obstructed drainage and a normal calibre ureter with a sharp cut-off. They were further assessed at laparoscopy and were found to have aberrant lower pole crossing vessels. All underwent laparoscopic mobilization of the lower pole vessels from the region of the PUJ thereby freeing the junction and relocating them superiorly onto the anterior wall of the pelvis. The median operating time was 120 min (range 60-240 min). The median hospital stay was 2 days (range 1-3 days). They were followed up for a median period of 12 months (range 6-36 months). All patients have remained asymptomatic. Ultrasound done at 6 months showed decreased hydronephrosis. MAG3 study showed improved drainage in 17, while 1 had poor drainage. This patient remains symptom free and is under regular follow up.

CONCLUSION

Laparoscopic vascular relocation is an unconventional technique in carefully selected patients with PUJO. It obviates disrupting an intrinsically normal PU junction and treats the cause rather than the effect. Our intermediate-term results are encouraging and further long-term assessment is needed.

Laparoscopic management of ureteropelvic junction obstruction in pediatric patients: a new approach to crossing vessels, crossing vein division, and upward transposition of the crossing artery

OBJECTIVE

To demonstrate the role of the laparoscopic approach for management of primary ureteropelvic junction obstruction (UPJO) using two different techniques in the pediatric age group.

MATERIAL AND METHODS

From April 2005 to October 2008, 63 pediatric patients underwent treatment of primary UPJO via a laparoscopic approach. Dismembered pyeloplasty was elected in 56 renal units while nine patients were managed by upward transposition of accessory renal artery after division of accessory renal vein. No JJ stent was required in these nine patients.

RESULTS

Mean age of patients was 61 (2-180) months. Mean operative time was significantly lower in those managed by transposition of aberrant vessels compared with dismembered pyeloplasty. The mean hospital stay was 6.4 (2-14) days for the dismembered technique and 2.1 (1-4) days for the vascular transposition approach. Significant improvement of obstruction was achieved in all of the patients who underwent the modified Hellstrom technique and in 92.81% of the renal units undergoing dismembered pyeloplasty.

CONCLUSION

The technique of laparoscopic transposition of crossing renal artery without violating collecting system may have a role in minimally invasive management of UPJO in selected pediatric patients. Further research with larger samples and a longer follow-up period is required.