European Urology

Abstract

Objective:

To determine the most suitable type of graft-free penile skin grafts or mucosal grafts from bladder or buccal regions - for urethral reconstruction in an animal model, as evaluated on the basis of angiogenic activity.

Methods:

Twenty-two male White New Zealand rabbits were randomly divided into four groups. In the control group (group O, n = 4) a simple urethrotomy and closure was performed, whereas a ventral urethral defect was created in groups A, B, and C and then bridged using the following onlay patches: free penile skin (group A, n = 6), buccal mucosal graft (group B, n = 6), and bladder mucosal graft (group C, n = 6). On the 21st postoperative day, the animals were sacrificed and the retrieved implants were subjected to macroscopic and microscopic analysis. The angiogenic activity was assessed with immunohistochemistry, using the anti-CD31 MoAb and the phosphatase antialkaline phosphatase procedure. The native vascularity of penile skin as well as buccal and bladder mucosa was assessed in rabbits from group O (n = 3). Statistical analysis was performed using the one-way ANOVA.

Results:

The angiogenesis in a magnification of ×200 in groups O, A, B, and C was 34.1 ± 4.1 (mean ± SD), 61.7 ± 6.4, 94.3 ± 6.4, and 91.5 ± 7.2 vessels per optical field, respectively. There were, statistically significant differences (p < 0.001) between groups A and B and between groups A and C, but not (p > 0.05) between groups B and C. The native vascularity of penile skin, buccal mucosa and bladder mucosa was 23.3 ± 3.0, 24.6 ± 3.7 and 17.0 ± 2.6 vessels per optical field, respectively.

Conclusion:

The viability of mucosal grafts from bladder or buccal regions is better than that of a free penile graft because of higher angiogenic activity. Although the mucosal grafts showed the same angiogenic activity, the buccal mucosa graft is preferable because of its easier harvesting.