Retroperitoneoscopic Simple Nondismembered Pyeloplasty with Da Vinci Si Assistance to Prevent Alignment Shift.

Aims: Retroperitoneoscopic simple nondismembered pyeloplasty (SNDP) with da Vinci Si assistance was developed because of a possible risk for alignment shift after retroperitoneoscopic diamond-shaped bypass pyeloplasty (Diamond-Bypass; DP). Outcomes of SNDP and DP were compared. Materials and Methods: For SNDP, a small longitudinal incision is made on the border of the dilated pelvis and narrowed ureter at the ureteropelvic junction (UPJ). Extending this incision toward the pelvis allows identification of mucosa while maintaining the integrity of surrounding tissues that are so thin and fragile that they will not influence lumen alignment. Data for DP were obtained from a previously published article. Results: For SNDP ( n  = 3), mean age at surgery was 2.67 years (range: 1-4), mean operative time was 176 minutes. Mean postoperative Society of Fetal Urology (SFU) grades for hydronephrosis were 1.2, 0.7, and 0.6, 1, 2, and 3 months after stent removal, respectively. Postoperative diethylenetriaminepentaacetic acid (DTPA) was normal ( n  = 3). For DP ( n  = 5) mean age at surgery was 4.3 years (range: 1-14), mean operative time was 189 minutes. Mean postoperative SFU grades were 2.8, 2.2, and 1.6, respectively. Postoperative DTPA was normal ( n  = 4) and delayed ( n  = 1). All SNDP and DP were asymptomatic by 3 months after stent removal. Conclusion: Both SNDP and DP have favorable outcomes. If the UPJ is located at the lowest end of the renal pelvis, SNDP may improve hydronephrosis more quickly.