Abstract
Ureteropelvic junction obstruction (UPJO) is the most common form of antenatal hydronephrosis, occurring in 1:500 to 1:1250 newborns. It is defined as a process of restriction to the flow of urine into the renal pelvis and ureter, as the degree of obstruction may develop with progressive deterioration of renal function. Previous studies have been developed to define the pathophysiologica…