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Updated: Feb 8, 2026

An Immature Murine Model of Reversible Unilateral Ureteral Obstruction
Published on: April 4, 2025
Ureteropelvic junction obstruction: endourologic relocation of laterally inserting ureters
Christopher S Ng1, Stevan B Streem
1Glickman Urological Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA. chris.ng@cshs.org
Purpose:
To describe a technique of endourologic management for ureteropelvic junction (UPJ) obstruction associated with lateral insertion of the ureter.
Patients And Methods:
Among 57 patients with primary UPJ obstruction selected to undergo retrograde endopyelotomy, 2 patients (3.5%) demonstrated a nondilated ureter inserting laterally along a hydronephrotic renal pelvis on retrograde pyelography. Using the hot-wire balloon catheter in one and a holmium laser inserted ureteroscopically in one, retrograde endopyelotomy was performed with the incision directed medially in order to marsupialize the ureter into the renal pelvis and to relocate the UPJ to the dependent portion of the medial aspect of the renal pelvis.
Results:
The hospital stay for both patients was 1 night, and there were no complications. The stent was removed 4 or 6 weeks postoperatively. Intravenous urography 6 weeks thereafter demonstrated relocation of the UPJ to a medial and dependent position, associated with prompt drainage of contrast medium and decreased pelvocaliectasis compared with preoperative studies. Both patients are asymptomatic.
Conclusions:
In cases of primary UPJ obstruction associated with lateral insertion of the ureter, the UPJ can be relocated to the medial and dependent portion of the renal pelvis using minimally invasive endourologic techniques. The dictum of performing a endopyelotomy incision laterally does not hold true in all patients and may compromise functional outcomes in cases where the ureteral insertion is nondependent and laterally positioned.
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