Impact of Renal Pelvic Denervation on Systemic Hemodynamics and Neurohumoral Changes in a Porcine Model.

INTRODUCTION: The blood pressure (BP) response to arterial renal denervation (RDN) is variable. METHODS: This study examined the effectiveness of renal pelvic denervation (RPD) on BP, heart rate (HR), norepinephrine (NE), and histopathology in 42 swine. NE levels were measured immediately, 7, 14, 30, and 90 days after RPD. Intra-arterial BP and HR were measured throughout RPD and after 14 days in 5 swine. RESULTS: During the procedure, RPD immediately reduced systolic BP (-20.6 ± 18.3 mm Hg), diastolic BP (-6.0 ± 8.3 mm Hg), and HR (-5.4 ± 5.6 bpm), which remained decreased at follow-up. The porcine kidneys had a mean NE reduction of 76% directly post procedure and 60% after 7 days, 64% after 14 days, 57% after 30 days, and 65% after 90 days. Histopathological examination confirmed nerve ablation. CONCLUSIONS: These preliminary findings suggest that the renal pelvis nerve ablation is an encouraging target for RDN. Clinical trials are required to test the feasibility of RPD in human hypertension.

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.

[Uretero-pelvic junction obstruction due to crossing pole vessel: contra vascular hitch]. / Subpelvine Stenose/Kreuzendes Gefäß ­ kontra vascular hitch.

Hydronephrosis in infants and children is most commonly due to a congenital, intrinsic obstruction of the uretero-pelvic junction. The Gold standard of care is defined as a dismembered pyeloplasty, nowadays mostly performed in a minimally-invasive procedure, either through a laparoscopic (also robotic-assisted) or retroperitoneoscopic approach. Less common is an extrinsic obstruction of the ureter or the uretero-pelvic junction caused by an aberrant crossing pole vessel, a condition more likely to affect children beyond infancy. This entity most often becomes apparent when it causes intermittent abdominal or flank pain. For this entity, Hellström described a surgical procedure avoiding dismembered pyeloplasty by hitching the crossing vessel in a tunnel at the pyelon. This has been increasingly advocated as a valuable therapeutic alternative to dismembered pyeloplasty. The discussion on whether dismembered pyeloplasty or a vascular hitch procedure is preferable to resolve the obstruction is controversial and ongoing. There is evidence in the literature that in the case of a crossing pole vessel an intrinsic stenosis of the ureter may additionally be present in up to 57 % of cases. However, this finding can only be proven histologically. The intraoperative aspect of a crossing pole vessel and the uretero-pelvic junction does not serve to discriminate between intrinsic and extrinsic stenosis. Therefore, a vascular hitch procedure bears the risk that a remaining intrinsic obstruction will be disregarded, which, in turn, may lead to urodynamic obstruction and consecutive loss of differential renal function. In addition, there is a general risk of compromising the perfusion of the affected kidney while hitching an aberrant vessel providing significant blood supply. Dismembered pyeloplasty can avoid a false selection of patients. In addition, there is sufficient evidence showing that dismembered pyeloplasty is a procedure with a low complication rate ranging from 2 to 3 %, providing very good results in functional outcome in terms of improving drainage and preserving differential renal function. Therefore, we prefer dismembered pyeloplasty as the method of choice for both the treatment of intrinsic as well as extrinsic uretero-pelvic junction obstruction.

Detection rate of crossing vessels in pediatric hydronephrosis: Transperitoneal laparoscopy versus open lumbotomy.

BACKGROUND: A bundle of crossing vessels (CV) supplying the lower pole of the kidney and causing mechanical obstruction of the ureteropelvic junction (UPJ) has been the subject of many discussions. During pyeloplasty, it is possible to overlook the CV. This may result in recurrent dilatation of the kidney and the need for re-surgery. OBJECTIVES: To compare the detection rate of CV in UPJ obstruction (UPJO) depending on the operational access applied (transperitoneal laparoscopy (LAP) vs open lumbotomy (OPEN)). Assessment of features that could indicate the presence of CV. MATERIAL AND METHODS: Two hundred and forty-six pediatric pyeloplasties were performed between January 2006 and July 2017 in the Department of Pediatric Surgery and Urology at the Wroclaw Medical University, Poland - 111 out of them by LAP and 135 by OPEN, on 98 girls and 148 boys. A retrospective analysis of the patient records for the detection of CV and characteristics of the CV before surgery was performed. RESULTS: Intraoperative CV causing obstruction of the UPJ in the LAP group were recognized in 34.2% (n = 38) of the patients, and within the OPEN group in 12.5% (n = 17) (p < 0.0001); 90% (n = 27) of patients with the diagnosed CV did not show congenital hydronephrosis. In 68% (n = 21) of the patients there were cases of recurrent renal colic. The presence of CV was suspected in 7.2% of kidney ultrasounds and in 12.5% in computed tomography (CT) urograms. CONCLUSIONS: The detection rate of CV in UPJO is statistically higher in LAP access than in open retroperitoneal lumbotomy. The distinguishing features of patients with CV are the lack of prenatal diagnosis for hydronephrosis and the presence of pain in the lumbar region.

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.

Feasibility of superb microvascular imaging to detect high-grade vesicoureteral reflux in children with urinary tract infection.

OBJECTIVE: To evaluate superb microvascular imaging (SMI) for the detection of high-grade vesicoureteral reflux (VUR). METHODS: We reviewed the patients with urinary tract infection who underwent renal US with SMI and VCUG. The subjects were divided into a VUR group, which included 17 patients (20 kidney units, KU) with high-grade reflux (grade 4 or 5) on VCUG, and a group without VUR including the same numbers of subjects. The direction of urine movement at the distal ureter and the renal pelvis was reviewed on SMI. SMI and VCUG results were compared. RESULTS: Urinary flow "jets" into the bladder and direction of the flow were detectable on all SMI examinations in both groups. In the group with VUR, 20 KUs had grade 4 (n = 11) or grade 5 (n = 9) reflux (bilateral VUR in 3 patients). Among 20 KUs with VUR, 15 (75%) showed a reversed ureteral jet and/or renal pelvic swirl sign on SMI. None of the patients in the group without VUR showed those findings on SMI. CONCLUSION: SMI enables detection of the direction of urinary flow. The presence of a reversed ureteral jet and/or renal pelvic swirl sign correlates with high-grade VUR with 75% accuracy. KEY POINTS: • Superb microvascular imaging is feasible in children with urinary tract infection. • SMI enables detection of the direction of urinary flow. • Presence of reversed flow correlates with high-grade vesicoureteral reflux.

Histopathology in Ureteropelvic Junction Obstruction With and Without Crossing Vessels.

OBJECTIVE: To determine if the histopathology of the ureteropelvic junction differs between those with and without crossing vessels who present with a ureteropelvic junction obstruction (UPJO). MATERIALS AND METHODS: Our database was queried for patients undergoing pyeloplasty (Current procedural terminology 50400, 50405, and 50544) between June 1, 2002, and March 10, 2016. We excluded patients with other renal anatomic abnormalities and patients undergoing surgery for upper tract tumor. One genitourinary pathologist reviewed all slides for muscle hypertrophy, fibrosis, edema, and inflammation. Statistics were modeled in SAS 9.4 (SAS, Cary, NC) using logistic regression with maximum likelihood. RESULTS: A total of 178 patients met the inclusion criteria, and pathology slides were available for 136 patients. Thirty-three patients had crossing vessels in association with a UPJO. The degrees of muscle hypertrophy (P = .89) and fibrosis (P = .17) were not predictive of etiology. The odds of a crossing vessel increased by 4.3 times (95% confidence interval 1.8-9.9) when edema was present (P = .009) and by 4.4 (95% confidence interval 1.4-13.7) times when inflammation was present (P = .0103). CONCLUSION: In the largest pathology series to date, histopathology showed increased inflammation in the presence of a crossing vessel but a similar composition of muscle and fibrosis. These data suggest that UPJO with an associated lower-pole vessel may represent a chronic process, which would explain why patients with a crossing vessel present later in life.

High-pressure balloon assessment of pelviureteric junction prior to laparoscopic "vascular hitch".

AIM: To assess if calibration of the ureteropelvic junction (UPJ) using a high-pressure balloon inflated at the UPJ level in patients with suspected crossing vessels (CV) could differentiate between intrinsic and extrinsic stenosis prior to laparoscopic vascular hitch (VH). MATERIALS AND METHODS: We reviewed patients with UPJO diagnosed at childhood or adolescence without previous evidence of antenatal or infant hydronephrosis (10 patients). By cystoscopy, a high-pressure balloon is sited at the UPJ and the balloon inflated to 8-12 atm under radiological screening. We considered intrinsic PUJO to be presente where a 'waist' was observed at the PUJ on inflation of the balloon and a laparoscopic dismembered pyeloplasty is performed When no 'waist' is observed we considered this to represent extrinsic stenosis and a laparoscopic VH was performed. Patients with absence of intrinsic PUJ stenosis documented with this method are included for the study. RESULTS: Six patients presented pure extrinsic stenosis. The mean age at presentation was 10.8 years. Mean duration of surgery was 99 min and mean hospital stay was 24 hours in all cases. We found no intraoperative or postoperative complications. All children remain symptoms free at a mean follow up of 14 months. Ultrasound and renogram improved in all cases. CONCLUSION: When no 'waist' is observed we considered this to represent extrinsic stenosis and a laparoscopic VH was performed. In these patients, laparoscopic transposition of lower pole crossing vessels ('vascular hitch') may be a safe and reliable surgical technique.

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.

High-pressure balloon assessment of pelviureteric junction prior to laparoscopic "vascular hitch"

ABSTRACT Aim To assess if calibration of the ureteropelvic junction (UPJ) using a high-pressure balloon inflated at the UPJ level in patients with suspected crossing vessels (CV) could differentiate between intrinsic and extrinsic stenosis prior to laparoscopic vascular hitch (VH). Materials and Methods We reviewed patients with UPJO diagnosed at childhood or adolescence without previous evidence of antenatal or infant hydronephrosis (10 patients). By cystoscopy, a high-pressure balloon is sited at the UPJ and the balloon inflated to 8-12 atm under radiological screening. We considered intrinsic PUJO to be present where a ‘waist’ was observed at the PUJ on inflation of the balloon and a laparoscopic dismembered pyeloplasty is performed When no ‘waist’ is observed we considered this to represent extrinsic stenosis and a laparoscopic VH was performed. Patients with absence of intrinsic PUJ stenosis documented with this method are included for the study. Results Six patients presented pure extrinsic stenosis. The mean age at presentation was 10.8 years. Mean duration of surgery was 99 min and mean hospital stay was 24 hours in all cases. We found no intraoperative or postoperative complications. All children remain symptoms free at a mean follow up of 14 months. Ultrasound and renogram improved in all cases. Conclusion When no ‘waist’ is observed we considered this to represent extrinsic stenosis and a laparoscopic VH was performed. In these patients, laparoscopic transposition of lower pole crossing vessels (‘vascular hitch’) may be a safe and reliable surgical technique.

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.

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.

Efficacy of Magnetic Resonance urography in detecting crossing renal vessels in children with ureteropelvic junction obstruction.

INTRODUCTION: An aberrant or accessory crossing renal vessel (CV) leading to the lower pole of the kidney is the most common extrinsic cause of uretero pelvic obstruction(UPJ) obstruction in a child and young adolescent.There is still controversy regarding there functional significance in obstruction Preoperative identification of such vessels may influence surgical management. OBJECTIVE: First aim is to determine the value of magnetic resonance (MR) urography in detecting crossing vessels in children with UPJ obstruction,comparing the data with postoperative findings and the second one is to evaluate morphologic and functional parameters in these hydronephrotic kidneys. MATERIALS AND METHODS: Between June 2009 and December 2012 we retrospectively reviewed MR urography records of one hundred and nine children with unilateral hydronephrosis at the University Children's Hospital. 68 (62.4%) were male and 41 (37.6%) were female,median age was 6.5 ± 5.7. Of the total number of patients, 30 (27%) underwent pyeloplasty, while 79 (72.5%) did not. The age at surgery ranged from 0.3 to 18 years (median 6.6 years). The indication for surgery was based on standard criteria (obstructed renal transit time with or without altered renal function of vDRF < 40%), and did not depend on the presence or absence of a crossing vessel.Consensus reviewes of the MR urography studies were compared with surgical findings. RESULTS: A crossing vessel (CV) was found upon surgery in 9 (33%) of 30 kidneys.On MRU, there was no crossing vessel in 21 kidneys, confirmed at surgery in 18. A crossing vessel was detected with MRU in 9 kidneys and confirmed at surgery in 6. Thus, the sensitivity of MRU was 66.7%, the specificity was 85.7%, the positive predictive value was 66.7%, the negative predictive value was 85.7% and the accuracy was 80%. There was no statistically significant difference in the detection of crossing vessels between MR urography and surgery (p = 0.004 and p < 0.01 respectively). Overall, MRU and surgery showed good agreement (κ = 0.524). CONCLUSION: Based on our results we suggest that MR urography is a reliable and safe diagnostic tool to determine crossing vessels in selected children with UPJ obstruction. Thus, MRU can substitute for other imaging modalities and provide detailed information about the morphology and function of the affected kidney KEY WORDS: Children, Crossing renal vessels, Hydronephrosis, Ureteropelvic function obstruction.

Ureteropelvic Junction Obstruction by a Long Intraluminal Polyp and a Concurrent Crossing Vein in a Symptomatic 8-Year-old Child.

Ureteropelvic junction obstruction due to intrinsic causes is often diagnosed antenatally during routine ultrasonography. Cases of extrinsic obstruction often present later and symptomatically, during childhood. We describe the rare case of an 8-year-old boy with a 2-day history of severe left flank pain, no fevers, and Society of Fetal Urology grade 3 hydronephrosis on ultrasonography. Laparoscopic dismembered pyeloplasty revealed a left ureteropelvic junction obstruction secondary to a large fibroepithelial polyp in the proximal ureter with a concomitant anterior crossing vein. We also provide a focused review of the pertinent published literature.

Detection of crossing vessels in pediatric ureteropelvic junction obstruction: Clinical patterns and imaging findings.

BACKGROUND: Pediatric ureteropelvic junction obstruction (UPJO) is caused by congenital intrinsic narrowing and/or a lower pole-crossing renal artery. When a crossing renal vessel (CRV) is missed at the time of pyeloplasty, a redo-pyeloplasty is often required. OBJECTIVES: The aims were to analyze clinical predictors for the presence of a CRV in UPJO and the utility of functional magnetic resonance urography (fMRU) in preoperative identification of a crossing vessel. METHODS: Using an Institutional Review Board approved registry database, we identified 166 patients from July of 2007 until January of 2014 who had undergone open, laparoscopic, or robotic assisted laparoscopic pyeloplasty at our institution. We abstracted data including age at surgery, preoperative symptoms, preoperative imaging findings, and whether or not a CRV was identified intraoperatively. Statistical analysis was performed on SPSS using the Mann-Whitney U test. RESULTS: Of the 166 patients identified, 78 were found to have a CRV at the time of surgery and 88 did not. The surgical approach was distributed as 104 robotic assisted laparoscopic, 51 open, and 11 pure laparoscopic. On univariate analysis, older age at presentation and pain at presentation predicted the presence of a CRV; antenatal hydronephrosis was a negative predictor, though 20 of 68 (25.6%) infants diagnosed with UPJO antenatally did have a CRV. Subgroup analysis of patients undergoing preoperative MRU showed a sensitivity of 88.2% and specificity of 91.7% for the detection of CRVs. DISCUSSION: This study confirmed the importance of looking for a crossing vessel in all cases, with the knowledge that increased age and pain at presentation were more likely to be associated with a crossing vessel. In addition, fMRU is a valuable source of information in the preoperative identification of the presence of a crossing vessel. The study has limitations including being retrospective in nature, and that the sensitivity of fMRU to identify CRVs was based on the read of an experienced uroradiologist who specializes in MRU, so may not correlate with the standard clinical read of an fMRU. CONCLUSION: This study confirms the need to maintain a high index of suspicion for the presence of a CRV when intervening in a clinically symptomatic older child, although 25% of infants with antenatally detected UPJO did have one too. Our subset analysis demonstrated that MRU is a reliable method of detecting crossing vessels.

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.

[Diagnosis and treatment of ureteropelvic junction obstruction caused by renal crossing vessels:an analysis of 24 cases].

OBJECTIVE: To investigate the diagnosis, treatment and surgical outcomes of ureteropelvic junction obstruction (UPJO) caused by renal crossing vessels. METHODS: The case records of 24 patients discharged from Peking University Third Hospital between June 2001 and September 2011 with the diagnosis of UPJO caused by renal crossing vessels were reviewed .Of the 24 patients, 17 were male and 7 were female patients. The mean age was 28 years (range, 2-63 years). The mean disease duration was 22.3 months (range, 7 days to 180 months). Of which, 4 patients underwent open surgery, and the other 20 patients were treated with laparoscopic surgery. Surgical approach was decided by operative conditions: adhesion release technique, dismembered pyeloplasty or Y-V anastomosisor, with or without cut off the crossing vessels. The kind of crossing vessels was recorded, and the effect of surgery was evaluated by follow-up. RESULTS: Fifteen cases were caused by oppressed renal crossing artery, 8 cases by renal crossing vein, and 1 case by 2 renal crossing arteries and 1 renal crossing vein. Among them, 11 cases were followed up successfully. Average follow-up time was 48.2 months (range, 13-120 months). Eight cases (8/11) were relieved, and 1 case (1/11) had no obvious improvement, another 2 cases (2/11) were aggravating. Among those 6 cases underwent adhesion release technique, 3 cases were relieved, 1 case had no obvious improvement, and 2 cases were aggravating. Five cases who underwent dismembered pyeloplasty was relieved significantly. CONCLUSIONS: Renal crossing artery is one of the main causes of UPJO, the crossing artery should be retained as far as possible. Crossing vessel oppression is not the only pathological cause of UPJO, so the treatment of UPJ constriction is also very important. Dismembered pyeloplasty seems to be the most efficacies treatment procedure for UPJO caused by repressed vessels, and the remission rate of adhesion release technique seems limited.

Retroperitonoscopic pyelopexy for pelviureteral junction obstruction with crossing vessel in adolescents: Hellstrom principle revisited.

OBJECTIVE: To present our new approach using a minimally invasive technique for the management of pelviureteral junction (PUJ) obstruction with a crossing vessel. MATERIALS AND METHODS: In December 2009 to December 2011, out of 23 cases of retroperitoneoscopic laparoscopic pyeloplasty, four adolescents presenting with PUJ obstruction due to an aberrant crossing vessel, with intermittent attacks of renal colic and mild dilatation of the renal pelvis and calyces, were operated by retroperitoneoscopic pyelopexy. A retroperitoneoscopic approach was used in all patients using three trocars. After dissection of the PUJ from the anterior crossing vessel, and ensuring good funneling of the PUJ that proved to show mild dilatation, an interrupted 3/0 polyglycolic suture was used to fix the renal pelvis to the psoas muscle away from the crossing vessel (pyelopexy). A retrograde DJ stent was placed at the end of the procedure. RESULTS: The four patients had a mean age of 18.25 years (16-20): 2 males and 2 females, two right sided and two left sided. Average operative time was 46 min (40-55). All patients were discharged on the same day. No intraoperative complications were encountered. The DJ stent was removed 6 weeks postoperatively. After a mean follow up of 2.125 years (6 months-3 years) no recurrences were observed. CONCLUSION: Retroperitoneoscopic pyelopexy is shown to be a reliable, effective, safe and minimally invasive technique for the management of PUJ obstruction with a crossing vessel in selected cases. Long-term follow up is needed to assess any recurrence or development of complications.

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.