Objective. To create a ureteral obstruction experimental model that can be proved through -DTPA renal scintigraphy and histopathological studies, without causing total renal function loss. Materials and Methods. Ten New Zealand white rabbits were submitted to a surgical experiment to create a model of unilateral obstruction to urinary flow. Surgery procedure provided unilateral ureteral obstruction (left kidney) to urinary flow and posteriorly was evaluated by -DTPA renal scintigraphy and histopathological study. -DTPA renal study was performed to detect and quantify signs of obstruction and to evaluate renal function. Statistical analysis was performed through the Student -test with a significance level of . Results. Nine of the ten rabbits presented left renal unit obstruction and one nonobstructive on the -DTPA and histopathological studies. All the right renal units, which were not submitted to surgical procedure, were nonobstructed by the studies. There was a general agreement between scintigraphy and histopathological results in both groups. Conclusion. The experimental model promoted the creation of ureteral obstruction in rabbits, confirmed by nuclear medicine scintigraphy and histopathology, and could be used in further studies to better understand urinary obstruction. 1. Introduction Pelvi-ureteric junction (PUJ) obstruction is one of the most frequent congenital anomalies of the urinary tract system. It is associated with pain, hydronephrosis, urinary tract infections, and eventually loss of renal function [1, 2]. It affects around 40% to 60% of all newborns with hydronephrosis [3], two times more common in males, and may be bilateral in 5% to 15% of cases [1, 4]. PUJ obstruction may be caused by intrinsic factors, like aperistaltic ureteral segment, obstructive fold mucosa, ureteral polyp, or ureteral stenosis [5]. Among extrinsic factors stands inferior renal polar vessel crossing anteriorly the PUJ [6]. Treatment varies from clinical observation to surgery. There are some surgical modalities available to correct the PUJ obstruction, differing from the open pyeloplasty to the latest in technology such as robotic assisted surgeries and endourological procedures [7–9]. Currently scientific literature is short in ureteral obstruction models that accurately reproduce the clinical and microscopic features of this infirmity [10–12]. The creation of a standardized experimental model that would be able to cause obstructive disturbance without leading to renal function loss would provide information capable of enhancing not only the diagnosis but
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