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Transmesenteric Laparoscopic Pyeloplasty in Trendelenburg Position for Horseshoe Kidney with Hydronephrosis
Published on: July 8, 2025
Laparoscopically Guided External Transanastomotic Stenting in Dismembered Pyeloplasty: A Safe Technique
Florian Obermayr1, Tobias Luithle1, Jörg Fuchs1
1Department of Pediatric Surgery and Pediatric Urology, University Children's Hospital, Tübingen, Germany.
Objective:
To describe a technique for insertion of external transanastomotic stents during laparoscopic dismembered pyeloplasty in children of all age-groups. To analyze stent-associated complications and changes in differential renal function (DRF).
Patients And Methods:
A retrospective study was performed of all patients up to 18 years of age undergoing laparoscopic pyeloplasty at our institution between March 2004 and December 2013. We analyzed patients in whom an external transanastomotic stent was placed using a specially constructed semicircular spear. Medical records were reviewed for stent-associated complications such as bleeding, stent dislocation, stent obstruction, and urinary tract infection. Additionally required secondary surgical procedures and changes in DRF were assessed.
Results:
A total of 150 patients (155 renal units [RU]) were included in the study, with a median patient age of 22 months (range, 1-214). Stents were removed after a median time of 7 days (range, 3-21). Stent-associated complications were observed in a total of 11 patients (12 RU), consisting of stent dislocations (6 RU), stent obstructions (3 RU), and persistent percutaneous leakage along the stent (1 RU) or after stent removal (2 RU). Stent-associated complications required a secondary surgical procedure in 4 RU. Neither significant blood loss nor urinary tract infection was associated with external transanastomotic stent placement. DRF did not change significantly after the procedure.
Conclusion:
External transanastomotic stenting during laparoscopic dismembered pyeloplasty using a specially constructed semicircular spear is a safe technique associated with a low complication rate and only rarely requires secondary surgical procedures for stent-related complications. This technique makes an additional anesthesia for stent removal unnecessary, as it is required for internal urinary diversion.

