Pyeloplasty in hydronephrosis: examination of surgical results from a morphologic point of view.

[BACKGROUND] Dilatation of the upper urinary tract is the most common congenital urogenital anomaly. Pyeloplasty is the therapy of choice in those patients with significant obstruction of the ureteropelvic junction. There are not many reports concerning the operative long-term results from a morphologic point of view. Furthermore, little information is available about children with giant hydronephrosis treated without resection of the dilated renal pelvis.

[METHODS] Between 1973 and 1993, 231 children with 262 renal units (kidney, renal pelvis, ureter) were treated at our institution. Giant hydronephrosis was observed in 52 renal units. The clinical and follow-up data were obtained from the patients' records. The dilatation of the upper urinary tract, confirmed by means of intravenous pyelogram, was divided into 5 grades.

[RESULTS] In 215 renal units, reconstructive surgery was performed without reduction of the renal pelvis. Revision of the pyeloplasty was necessary in 5 of the 215 renal units. The dilatation of the upper urinary tract improved or remained stable in 99.4% of the renal units during the follow-up period of 4.8 years (range, 1 month to 21 years).

[CONCLUSION] Surgical reconstruction of the ureteropelvic junction obstruction is a safe and successful procedure. The excision of the dilated pelvis does not seem to be necessary, even in patients with giant hydronephrosis.