Pyeloplasty in children: is there a difference in patients with or without crossing lower pole vessel?

Transposition and fixation of lower pole crossing vessel in children with ureteropelvic junction obstruction: A STROBE-compliant study

Chapman and Hellstrom techniques are typically employed to transpose renal lower pole crossing vessels (LPCVs). Both procedures have certain limitations. We investigated the midterm outcomes in pediatric patients in whom LPCV-induced ureteropelvic junction obstruction was treated with either dismembered Anderson-Hynes pyeloplasty or upward transposition coupled with a new technique to fix the LPCV.We retrospectively compared Anderson-Hynes pyeloplasty to the new technique in terms of outcome. LPCV transposition was considered feasible in patients in whom the diuretic loading test revealed a decrease in the pelvic volume after correction of vascular compression as well as absence of structural changes in the ureteropelvic junction (UPJ) and hemodynamic compromise of the lower renal pole. The fascial flap was passed below the LPCV to form a "hammock". The free edge of the flap was sutured to its base.Group 1 consisted of 102 (69.9%) patients (median age: 7.9 years) undergoing dismembered Anderson-Hynes pyeloplasty, while group 2 included 44 (30.1%) patients (median age: 8.4 years) treated with upward transposition and the new technique to fix the LPCV. No intra-operative complications or conversions occurred in either group. Redo-pyeloplasty was performed in 3 (2.9%) children of group 1 and 1 (2.3%) child of group 2. Renal ultrasonography conducted 12 months after surgery revealed similar anteroposterior diameters of the renal pelvis in groups 1 (7.9 ± 8.1 mm) and 2 (6.0 ± 2.9 mm). Patients in both groups showed a non-significant median increase in differential renal function at follow-up after at least 1 year after surgery (group 1: 36% [33.3; 40.5] vs 36.5% [35.3; 41.0]; group 2: 41% [37.5; 46.0] vs 43% [39; 46]).In our patients, the new technique for laparoscopic or open fixation of the obstructing vessel after transposition was effective, reproducible, and devoid of limitations typical for the Chapman and Hellstrom techniques. We recommend Anderson-Hynes pyeloplasty in children with a history of hydronephrosis diagnosed antenatally, recurrent abdominal pain, intra-operative absence of peristalsis across the UPJ, high location of the UPJ at the renal pelvis, or intra-operative absence of volume reduction of the renal pelvis upon furosemide testing.

Hydronephrosis in Children Caused by Lower Pole Crossing Vessels-How to Choose the Proper Method of Treatment?

Objectives: Assessment of the efficacy of intraoperative diagnosis between extrinsic and intrinsic UPJO in children. Assessment of the efficacy of laparoscopic vascular-hitch procedure in UPJO caused by lower pole crossing vessels (CV). Materials and Methods: Between 2008 and 2017, 47 laparoscopic procedures were performed with the CV discovered intraoperatively. CV were translocated cephalad, and the UPJ was carefully inspected. The Chapman's vascular hitch procedure was accomplished in the case of decreasing sizes of the pelvis and clear, visible peristalsis of the UPJ (31 patients). In the other cases, Anderson-Hynes (A-H) pyeloplasty with posterior translocation of the CV was performed (16 patients). Results: The median age at operation was 6 years (range 1-16) in VH and 6 years (range 2-17) in A-H (p = 0.4635). Prenatal dilatation of kidney was diagnosed in 18.7% of VH and 10% of A-H cases (p = 0.5474). Success was achieved in 16 (100%) patients in the A-H and in 29 (93.54%) in the VH groups. Two patients (6.5%) in VH required repeated surgery because of a misdiagnosed intrinsic obstruction. Median operation time in VH was 80 min (range 40-105) and was 105 (range 70-225) in A-H (p < 0.05). Conclusions: The intraoperative selection based on intraoperative pelvis and UPJ appearance after vessel transposition is sufficient in majority of cases. Laparoscopic vascular hitch seems to be effective and safe procedure, but can only be performed on carefully selected patients. In case of misdiagnosis, reoperation is possible with the same laparoscopic access.

Imaging in children with unilateral ureteropelvic junction obstruction: time to reduce investigations?

The objective of the study was the development of an abridged risk-stratified imaging algorithm for the management of children with unilateral ureteropelvic junction obstruction (UPJO). Data on timing, frequency and duration of diagnostic imaging in children with unilateral UPJO was extracted retrospectively. Based on these findings, an abridged imaging algorithm was developed without changing the intended management by the clinicians and the outcome of the individual patient. The potential reduction of imaging studies was analysed and stratified by risk and management groups. The reduction in imaging studies, seen for ultrasound (US) and functional imaging (FI), was 45% each. On average, this is equivalent to 3 US and 1 FI studies less for every patient within the study period. The change was more pronounced in the low-risk groups. Progression of UPJO never occurred after 2 years of age and all secondary surgeries were carried out until the age of 3.

CONCLUSIONS

Although our findings need to be validated by further prospective research, the developed imaging algorithm represents a risk-stratified approach towards less imaging studies in children with unilateral UPJO, and a follow-up beyond 3 years of age should be considered only in selected cases at the discretion of the clinician. What is Known: • ultrasound and functional imaging represent an integral part of therapeutic decision-making in children with unilateral ureteropelvic junction obstruction • imaging studies cannot accurately assess which patients are in need of surgical intervention, therefore close, serial imaging is preferred What is New: • a new, risk-stratified imaging algorithm was developed for the first 3 years of life • applying this algorithm could lead to a considerable reduction of imaging studies, and also the associated risks and health-care costs.

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.

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.

Unilateral Hydronephrosis and Renal Damage after Acute Leukemia

A 14-year-old boy presented with asymptomatic right hydronephrosis detected on routine yearly ultrasound examination. Previously, he had at least two normal renal ultrasonograms, 4 years after remission of acute myeloblastic leukemia, treated by AML-BFM-93 protocol. A function of the right kidney and no damage on the left was confirmed by a DMSA scan. Right retroperitoneoscopic nephrectomy revealed 3 renal arteries with the lower pole artery lying on the pelviureteric junction. Histologically chronic tubulointerstitial nephritis was detected. In the pathogenesis of this severe unilateral renal damage, we suspect the exacerbation of deleterious effects of cytostatic therapy on kidneys with intermittent hydronephrosis.