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.

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.

[Modified laparoscopic scissors: a new instrument for performing endopyelotomy]. / Tijera laparoscópica modificada: un nuevo instrumento para realizar endopielotomía.

OBJECTIVE: The safety and success of antegrade endopyelotomy in the treatment of ureteropelvic junction (UPJ) stenosis have been documented in numerous literature reports over the last decade. We show a new available alternative to the way incision is performed. METHODS: Endopyelotomy with modified laparoscopic scissors was performed in 18 patients; 12 presented with primary obstruction and 6 with secondary obstruction. 3 mm laparoscopic scissors with one end sharpened and adapted for this technique are introduced through a nephroscope. A small puncture through the renal pelvis wall is made in the posterolateral position using the scissors' end. After that, scissors are opened under permanent endoscopic control as far as to visualization of the peripyelic space, continuing then with the internal edge of the scissors down to the UPJ. Visual control allowed us to coagulate any vessel and to avoid the bigger calibre ones. At the end of the procedure an endopyelotomy stent was placed over the safety guide wire. RESULTS: Results were good in 17 patients (94%); symptomatic relief and adequate pass of contrast to proximal ureter were observed in the remaining case, although pyelocalicilar dilation was not improved. Three vessels adjacent to the UPJ (16.6%) were discovered through the performed pyelotomy incision. Operative times were lower than 2 hours. Blood losses were minimal and patient recovery uneventful allowing hospital discharges within 48 hours. CONCLUSIONS: To use 3 mm laparoscopic scissors allows to perform endopyelotomy without changing endoscopes, precisely cutting due to retroperitoneum visualisation, and offers the chance to coagulate small calibre vascular elements and to avoid those of bigger size.

Vascular anatomy at the ureteropelvic junction.

In 65% of the cases regarding the ventral surface of the UPJ, there was a prominent artery, vein, or both in close relation to the ventral surface of the UPJ. In only 6.8% there was an inferior polar artery crossing anteriorly to the UPJ. Therefore, many of the vessels visualized close to the UPJ and described as anomalous and etiologic in obstruction are normal segmental arteries that do not cause UPJ obstruction. In 26.7% of cases regarding the dorsal surface of the UPJ, there was a vessel crossing at or lower than 1.5 cm above the posterior surface of the UPJ. On the basis of our anatomic findings, we advise that in endopyelotomy, the incision along the stenotic UPJ be created only at its lateral aspect.

The dilemma of the crossing vessel at the ureteropelvic junction: precise anatomic study.

To maximize the success rate of endopyelotomy with minimal risk of complications, some debate still persists on the technique of incising the ureteropelvic junction (UPJ), patient selection, and prognostic factors. Also, some controversy exists concerning the vascular complications associated with the procedure. In order to give anatomic background to better clarifying the issue of a crossing vessel at the UPJ, we analyzed its vascular anatomic relations in 546 kidneys divided as following: 82 three-dimensional polyester resin corrosion endocasts of the collecting system together with the intrarenal arteries, 52 endocasts of the collecting system together with the intrarenal veins, 146 endocasts of the collecting system together with the intrarenal arteries and veins simultaneously, and 266 in situ dissected kidneys. In 65% of the endocasts, we found a prominent artery, vein, or both in close relation to the ventral surface of the UPJ. Among these cases, in 45%, the relation was with the inferior segmental artery. With respect to the presence of multiple renal arteries, in only 6.8% of the cases did an inferior polar artery cross anteriorly to the UPJ. In 6.2% of the endocasts, there was a direct relation between a large vessel and the dorsal surface of the UPJ. In additional 20.5% of the cases, there was a vessel crossing lower than 1.5 cm above the posterior surface of the UPJ. Considering these anatomic findings, it is conceivable that many of the vessels seen during angiography in a close relation to the UPJ and described as anomalous and etiologic in obstruction would be normal segmental arteries that do not cause UPJ obstruction. Also, on the basis of the anatomic findings, we advise that in endopyelotomy, the incision along the stenotic UPJ wall be created only at its lateral aspect.

Ureteropelvic junction stenosis: vascular anatomical background for endopyelotomy.

To help endourologists perform endopyelotomy safely and efficiently with a reduced risk of vascular complications, we analyzed the vascular relationships to the ureteropelvic junction in 146, 3-dimensional endocasts of the kidney collecting system together with the intrarenal arteries and veins. There was a close relationship between a prominent vessel (artery and/or vein) and the anterior surface of the ureteropelvic junction in 65.1% of the cases, including the inferior segmental artery with a tributary of the renal vein in 45.2% and an artery or vein in 19.9%. In the remaining 34.9% of the cases the anterior surface of the ureteropelvic junction was free of vessels. There was a direct relationship between a prominent vessel (artery and/or vein) and the posterior surface of the ureteropelvic junction in 6.2% of the cases, including an artery and vein in 2.1%, and just an artery in 1.4%. In all cases (3.5%) of an artery crossing at the posterior surface of the ureteropelvic junction, this vessel was the posterior segmental artery (retropelvic artery). In 2.7% of the cases the relationship of the prominent vessel was just with a posterior tributary of the renal vein, and in 20.5% a vessel crossed lower than 1.5 cm. above the posterior surface of the ureteropelvic junction. Among these latter cases the vessel was an artery (posterior segmental artery) in 6.8%. In the remaining 73.3% of the cases the posterior surface was free of vessels up to 1.5 cm. above the ureteropelvic junction. Due to the anatomical findings, we advise that posterior and posterolateral incisions at the ureteropelvic junction be avoided, and that deep incision alongside the ureteropelvic junction stenotic wall be done only laterally.

Anatomical relationship between the renal venous arrangement and the kidney collecting system.

The anatomical relationships between the renal venous arrangement and the pelviocaliceal system were studied in 52, 3-dimensional polyester resin corrosion endocasts. In 53.8% of the cases, there were 3 large venous trunks and in 28.8% there were 2 venous trunks joining to form the main renal vein. Intrarenal veins demonstrated free anastomoses that were disposed in 3 systems of longitudinal arcades (stellate, arcuate and interlobar veins). There were large venous collars around caliceal necks and also horizontal arches crossing over calices to link anterior and posterior veins. In 84.6% of the cases the upper caliceal group was encircled anteriorly and posteriorly by venous plexuses, which coursed parallel to the infundibulum. In 50.0% of the cases the lower caliceal group also was enriched by 2 venous plexuses. A close relationship existed between a large inferior tributary of the renal vein and the anterior aspect of the ureteropelvic junction in 40.4% of the cases. In 69.2% of the cases there was a posterior (retropelvic) vein: in 48.1% this vein had a close relationship to the junction of the pelvis with the upper calix and in 21.1% it crossed the middle posterior surface of the renal pelvis.