The histopathological effect of tissue adhesive on urethra wound healing process: An experimental animal study

Introduction and objective: The present study aimed to determine the histopathological effect of Tisseel tissue adhesive on the urethral wound healing process after urethroplasty in a rat model.

Study design: A total of 24 animals were randomly allocated into three groups: Group 1; control group (n = 6); Group 2; suture-closure group (n = 9); and Group 3; suture + adhesive group (n = 9). In group 2, an incision 4 mm long was made on the ventral skin of the penis along the midline from the glans penis, to open the dartos muscle, corpus spongiosum, and urethra. Next, initially, the urethra alone, and then the layers up to the skin were covered in layers with 8/0 vicryl interrupted sutures. Group 3 underwent the same procedures as group 2, but after the urethra was repaired 0.1 cc of Tisseel tissue adhesive was applied over the urethra. Penile tissue samples were obtained 21 days later, and tissue samples were sent for histopathological analysis.

Results: Urethral epithelial thickness and connective tissue thickness in group 3 were higher than in group 1 and group 2. Fibrosis in group 3 was higher than in group 2. The difference in inflammation between group 3 and group 2 was not significant. There was no significant difference in microvessel density between group 2 and group 3.

Discussion: Both increased fibrosis and connective tissue thickness were noted in group 3 compared to group 2 and group 1. These increases may have been caused by the hemostatic effect of the Tisseel adhesive and its triggering of fibroblast growth factors. The epithelial thickness increased significantly in group 3 and group 2 compared to group 1. This increase in tissue thickness without an increased number of epithelial cells can be explained by the development of oedema.

Conclusion: The present study suggests that while Tisseel tissue adhesive increases connective tissue thickness and fibrosis, it does not demonstrate a prolonged inflammation or increased neovascularization in the urethral wound at 3 weeks after surgery. The data obtained in our study does not support the use of Tisseel in urethroplasty surgery. The results obtained in this study demonstrate a significantly higher formation of fibrosis (scar tissue), which underlines the importance of new studies to identify new treatments for urethral wound healing after urethra trauma or surgery.