Laparoscopic Pyeloplasty in the Animal Model

PURPOSE: Laparoscopic pyeloplasty has been associated with long operative times. This study proposed to evaluate the feasibility of two different laparoscopic techniques for the performance of pyeloplasty repair of secondary ureteropelvic junction (UPJ) obstruction. MATERIALS AND METHODS: Sixteen female Yucatan mini-pigs underwent general anesthesia for cystoscopy, retrograde pyelography, urine culture and a baseline renal scan. Unilateral UPJ obstruction was created by ligating the UPJ over a 5F catheter. Six weeks later a laparoscopic pyeloplasty was performed utilizing an intracorporeal suturing technique and the Lapra-Ty suture clip or the Endostitch device with intracorporeal knot tying. Four control animals underwent only cystoscopy and in/out ureteral catheterization. In the study animals the ureteral stent was maintained for six weeks and at six weeks, three months and six months post-pyeloplasty the animals underwent the previously mentioned studies. At six months post-pyeloplasty the animals were euthanized and the UPJ was calibrated. Histopathology was obtained on the ureter below the anastomosis, at the anastomosis, above the anastomosis and on a renal biopsy. RESULTS: All planned laparoscopic pyeloplasties were completed. However, the stricture model was too severe in that most animals developed 40-45% decrease in renal function in the kidney following ipsilateral UPJ ligation. There was no significant difference between the two pyeloplasty techniques with respect to operative time to perform the pyeloplasty (mean of 40 minutes), post-pyeloplasty ureteral caliber (7.5-8.0 F), serum creatinine or healing scores at, above or below the anastomosis. CONCLUSION: Laparoscopic pyeloplasty can be performed equally successfully with the Endostitch device and intracorporeal knot tying or with the intracorporeal suturing technique and Lapra-Ty clips. The resultant pyeloplasty is also equivalent for the two techniques.