RECONSTRUCTIVE SURGERY OF THE URETHRA - A PILOT-STUDY IN THE RABBIT ON THE USE OF HYALURONAN BENZYL ESTER (HYAFF-11) BIODEGRADABLE GRAFTS

We investigated the outcome of reconstructive surgery of the urethra t hrough guides composed of a novel biodegradable and highly biocompatib le polymer, Hyaff-11. A tract of about 1.5 cm of the rabbit pendulous urethra was totally resected and replaced by a Hyaff-11 tubular graft. Eleven animals were analysed at each of the time points ranging from 7 days to 4 weeks following surgery. Histological and radiological eva luation showed a satisfactory remodelling of the neo-urethra around th e implant. The regenerated connective tissue connected both urethral s tumps within the first 7 days. On postoperative week 3, the Hyaff-11 g uide had disappeared. At the 4-week time point the retrograde urethrog ram showed a good distensibility of the neourethra. The regenerated st roma consisted of fibroblastic cells, and collagenous and elastic fibr es. The neo-epithelium was pluristratified and exhibited cells of the cuboidal type.