Performance of total ureteral replacement in pigs by using transversely retubularised bowel segment (Monti technique) [Domuzlarda Transvers Retübülarize Baǧirsak Segmenṫ i (Monṫi Tekṅiǧ̇ i) ̇ ile Total Üreter Replasmani Uygulamasi]

Abstract

Introduction: The aim of our study was to evaluate the results of a new technique named as transversely retubularised bowel segment (TRBS) for total ureteral replacement in pigs. Materials and Methods: We have performed left total ureteral replacement with 2 tubes which were formed by TRBS technique via flank incision in 6 pigs with a mean age of 6 months (5-7) and a mean weight of 25 kg (20-30). Pigs underwent the operations under general anesthesia. TRBS, prepared using two ileum segments each 2-2,5 cm in length, were anastomosed end to end to get a 10-12 cm long tube. After ureterectomy, total ureteral replacement was performed in the left ureter and right ureter was used as the control group. Between the days of 30 and 40, double J catheters were taken out by a second operation via suprapubic transvers incision. Pigs were evaluated by excretory urography approximately 2.5 months after surgery and then sacrified thereafter, harvesting the kidneys, ureters and the bladders en bloc for macroscopic and histologic examination by light and electron microscopes. Results: The mean operation time was 240 min. (210-300) and four pigs could end up in the study. One pig died due to the bleeding from one of the mesenteric arteries in postoperative first day and 1 pig died during the operation due to respiratory arrest. The double J catheters of 2 pigs couldn't be taken out because of catheter migration. Postoperative excretory urograms revealed that the excretion of the contrast material were delayed and there were grade 3-4 hydroureteronephrosis in the upper half of the ureter in three pigs. In the other pig, in which double J catheter couldn't be taken out, the catheter was out of the ureter. Catheterization displayed that the lumen were patent, however stenosis was detected only at the anastomosis region between the 2 ileal tubes. In the histologic evaluation, at the anastomosis sites between the two ileal tubes and in the surrounding connective tissue, moderate to marked fibrosis was seen consistent with stenosis. Conclusion: Although segmental ureteral replacement using TRIS technique was a choice in ureter injury, it was unsuccessful in total ureteral replacement according to the results in the current study. Marked fibrosis at the anastomosis sites between the tubes was accussed. In order to clarify this topic, further animal studies should be performed.