Objectives: To develop a new experimental model of partial ureteral obstruction that is simple, reliable, variable, and reversible.
Methods: A 6 F ureteral catheter was inserted into the left ureteral orifice and was cut 2 cm distal to the orifice. The most distal part of the ureter was ligated around the catheter. The catheter lumen was partially obstructed by insertion of stylets of three different diameters. The catheter and the stylet were fixed inside the bladder. The model was tested in 12 dogs, which were stratified into three groups according to the diameter of the obstructing stylet. All the dogs were subjected to intravenous urography (IVU) and technetium-99m-mercaptoacetyltriglycine (99mTc-MAG3) renal scan at 2 and 4 weeks following induction of partial ureteral obstruction.
Results: Three different grades of hydroureteronephrosis were obtained according to the diameter of the obstructing stylet. The IVU and 99mTc-MAG3 renal scan studies were repeated at 2 and 4 weeks following removal of the ureteral catheter and ureteroneocystostomy and showed marked improvement in the configuration and function of the corresponding renoureteral units.
Conclusions: Our experimental model fulfills the requirements for a useful model of partial ureteral obstruction, namely, simplicity, reliability, variability, and reversibility.