RECENT MODALITIES IN MANAGEMENT OF URETEROPELVIC JUNCTION OBSTRUCTION

Abstract

The management of ureteropelvic junction obstruction I (UPJO) in infants is difficult because the diagnosis of a significant obstruction cannot always be established with certainty m asymptomatic infants with unilateral hydronephrosis and normal renal function. This article reviews I the currently used methods of diagnosis and treatment.

The cause of congenital UPJO has been the subject of much speculation. Classically, obstructions are classified as intrinsic and extrinsic. Intrinsic obstructions are attributed to alterations in the amount and orientation of the muscle layers of the UPJ, increased collagen content, and alterations of peristalsis. Extrinsic obstructions are attributed to "crossing vessels". The role of such vessels is debatable. They tend to be normal variants of renal vascular anatomy and are in a normal location. It is likely that, as the pelvis dilates as the result of an intrinsic obstruction, it gets draped over a branch of the renal artery supplying the lower pole of the kidney, giving the appearance that the vessel is the cause of the obstruction. Division of vessels never solves the obstruction. When patients are selected properly for surgery and evaluated by ante-grade or retrograde pyelography, the common finding is a narrow segment of the upper ureter (ureteral hypoplasia) accompanied by a variable amount of tortuosity and periureteral fibrosis. Ureteral valves and fibroepithelial polyps are rare causes of obstruction.