Histerocystoplasty: a novel surgical procedure in the rat.

BACKGROUND: Enterocystoplasties are associated to complications. To avoid them, different types of tissue templates have been used to augment the bladder and induce native bladder regeneration. MATERIALS AND METHODS: A novel surgical technique for bladder reconstruction using autologous uterine tissue was evaluated in a rat model. Forty-two female Wistar rats were randomly allocated into three groups: sham-operation hysterocystorrhaphy (n = 12), hysterocystoplasty (n = 18), and control (n = 12). Two weeks after surgery, ultrasound examination of the bladder was performed. At 2, 4, or 6 mo after surgery, the rats were anesthetized and blood and urine samples were taken. They were then euthanized and post-mortem and histologic examination were performed. Ultrasound examination, analytical parameters and weight control, as well as gross and histologic examination were performed in all the operated animals. The statistical analysis was performed using Kruskal-Wallis and the extension of Fisher's exact tests. Significance was set at 5% (P < 0.05). RESULTS: Serum chemistry, blood count and peripheral blood smears, electrolytes, and urinary parameters were all within the normal range for the rat. Histologic sections of the surgically augmented zone between the bladder and uterine horn demonstrated urothelial epithelization, providing adequate coverage of the transition area in 72.22% of the rats that underwent hysterocystoplasty. CONCLUSIONS: The hysterocystoplasty was technically viable in all the cases and proved to be an easy and safe surgical model for bladder reconstruction. All animals were healthy after surgery and all systemic parameters analyzed were within normal physiologic range for the rat.

Bladder autoaugmentation with protective autologous uterine flap. Experimental study in the rat.

INTRODUCTION: Enterocystoplasties are associated to complications. We developed a surgical technique for bladder autoaugmentation using autologous uterine flap in the rat, to try and improve the post-surgical evolution. METHODS: 36 female Wistar rats were randomly allocated into following groups: Group 1: Control (n = 12) for analytical parameters, Group 2: Sham-operation hysterocystorrhaphy (n = 12) and Group 3: Bladder autoaugmentation with autologous uterine flap (n = 12). Two weeks after surgery ultrasound examination of the bladder was performed. At 8 weeks and 24 weeks, blood and urine samples were taken. Post-mortem evaluation was performed and urogenital apparatus removed for gross and microscopic examination. The statistical analysis was done using the Kruskall-Wallis and the extension of the Fisher's exact test. Significance was set at 5% (p < 0.05). RESULTS: Serum chemistry, blood count and peripheral blood smears, electrolytes and urinary parameters were all within the normal range for the rat. No abnormal findings were observed during ultrasound examination. There was no mortality or other surgical complications. Post-mortem evaluation revealed no dilation of bladder, uterus or upper urinary tract. Uroliths were not observed. Histology of the augmented area demonstrated an excellent union between the bladder and the protective uterine flap. A normal urothelial layer was maintained. CONCLUSIONS: The use of autologous uterine flap to perform bladder autoaugmentation in the rat proved a safe and suitable surgical technique to augment the bladder. The major advantage is the avoidance of the complications observed in other surgical techniques for bladder augmentation, like enterocystoplasties, where gastrointestinal tract epithelium is incorporated into the urinary tract.