CREATION OF A MODEL OF BLADDER EXSTROPHY IN THE FETAL LAMB

Purpose: To our knowledge we describe the first reproducible large ani mal model to mimic the congenital birth defect of classic bladder exst rophy. Materials and Methods: Eight male and 15 female fetal sheep und erwent in utero surgical creation of classic bladder exstrophy. The fe tus was then replaced within the amniotic sac and allowed to come to t erm. A sham procedure was performed on 16 male fetuses. Results: After the creation of bladder exstrophy 53% of the female and 62% of the ma le fetuses survived to full term and through delivery. Of the male fet uses that underwent sham surgery 62% also survived through delivery. L ambs with exstrophy were born with the bladder wall in continuity with the abdominal wall and exposed to the environment. The sham operated male lambs had a well healed abdominal scar. Conclusions: To our knowl edge we have devised the first reproducible large animal model of blad der exstrophy. This model will be useful in studying bladder developme nt and composition in the patient with exstrophy. It may also serve as a useful tool in developing innovative forms of surgical treatment fo r such patients.