Technical modifications of double-J stenting for retroperitoneal laparoscopic dismembered pyeloplasty in children under 5 years old

Both antegrade stenting and retrograde stenting for retroperitoneal laparoscopic dismembered pyeloplasty in children have many disadvantages. In this work, we tried using an alternative technique of modified antegrade (MAG) double-J stenting for retroperitoneal laparoscopic dismembered pyeloplasty in children under 5 years old, analyzed our results using the conventional antegrade (CAG) and the MAG techniques of stent insertion for this procedure, and reported our experience with these techniques. Between December 2002 and July 2010, 77 children under 5 years old with ureteropelvic junction obstruction underwent retroperitoneal laparoscopic dismembered pyeloplasty. CAG and MAG double-J stenting were attempted, in the first 36 cases (mean age 27.1 months) and the following 41 cases (mean age 25.4 months), respectively. The stents were removed 4-6 weeks later via cystoscopy. Follow-up studies were performed with ultrasonography and intravenous urography at 3 and 12 months postoperatively. The results showed that successful stent placement without malpositioning was achieved in 31 of 36 (86%) and all 41 (100%) cases, in the CAG and MAG groups, respectively. The common factor of unsuccessful stent was the inability to across the ureterovesical junction. The mean stent insertion time was 10 min 54 s and 12 min 46 s in the CAG and MAG groups, respectively. The mean operating time was 176 min and 185 min in the CAG and MAG groups, respectively. No stent malpositioning occurred in the MAG group; in the CAG group, two children had a malpositioned stent in the distal ureter and one child presented with a severe hematuria. Twelve months follow-up showed no new onset of hydroureteronephrosis and hydronephrosis. Thus we concluded that the MAG double-J stenting seems more reliable than CAG stenting for retroperitoneal laparoscopic dismembered pyeloplasty in children under 5 years old, with greater success and lower complication rates.