A Novel Approach to Penile Augmentation Urethroplasty Using Buccal Mucosa and Amniotic Membrane: A Pilot Study in a Rabbit Model

Abstract

To evaluate and compare the success of amniotic membrane (AM) and buccal mucosa (BM) grafts and simultaneous use of both in penile augmentation urethroplasty in rabbits. A total of 12 New Zealand rabbits were divided into 3 groups by grafting style: Group 1 (AM), Group 2 (BM), and Group 3 (simultaneous use of BM and AM). In all animals, a standardized urethral defect was created. BM and AM were obtained from the rabbits. Solely AM grafts were affixed to the defects in Group 1, solely BM grafts were affixed to the urethral defects in Group 2, and simultaneous AM + BM grafts were affixed in Group 3. At 4 and 8 weeks, the penises were subject to histological assessment of subepithelial fibrosis, epithelial transformation, and inflammatory reaction. Stenosis was detected in none of the groups. A dehiscence was developed in one rabbit in Group 1 and a fistula was developed in one rabbit in Group 2. After 4 weeks, minimal subepithelial fibrosis and inflammatory reaction were observed in Group 2, while subepithelial fibrosis was not in Groups 3. After 8 weeks, subepithelial connective tissue proliferation was moderate in Group 2, at both 4th and 8th weeks in Group 2. After 8 weeks, the best epithelial transformations were observed in Group 3. In an animal model, the simultaneous use of AM and BM grafts following acute urethral injury may be feasible for penile augmentation urethroplasty. Further study is needed.