Dorsal tunica vaginalis graft plus onlay preputial island flap urethroplasty: Experimental study in rabbits

Leslie, Bruno; Barboza, Luiz L.; Souza, Petrus O.; Silva, Paulo S.; Delcelo, Rosana; Ortiz, Valdemar; Macedo, Antonio

doi:10.1016/j.jpurol.2008.09.003

« Previous Next »Journal of Pediatric Urology
Volume 5, Issue 2 , Pages 93-99, April 2009

Dorsal tunica vaginalis graft plus onlay preputial island flap urethroplasty: Experimental study in rabbits

Bruno Leslie
- Federal University of São Paulo, Rua Napoleao de Barros, 715 2 Andar, São Paulo, SP 04024-002, Brazil
Luiz L. Barboza
- Federal University of São Paulo, Rua Napoleao de Barros, 715 2 Andar, São Paulo, SP 04024-002, Brazil
Petrus O. Souza
- Federal University of São Paulo, Rua Napoleao de Barros, 715 2 Andar, São Paulo, SP 04024-002, Brazil
Paulo S. Silva
- Federal University of São Paulo, Rua Napoleao de Barros, 740 Ed. Cirurgia Experimental, São Paulo, SP 04024-002, Brazil
Rosana Delcelo
- Federal University of São Paulo, Rua Napoleao de Barros, 740 1 Andar, São Paulo, SP 04024-002, Brazil
Valdemar Ortiz
- Federal University of São Paulo, Rua Napoleao de Barros, 715 2 Andar, São Paulo, SP 04024-002, Brazil
Antonio Macedo Jr.
- Federal University of São Paulo, Rua Napoleao de Barros, 715 2 Andar, São Paulo, SP 04024-002, Brazil
- Corresponding author. Tel.: +55 11 3287 0639; fax: +55 11 3287 3954.

Received 30 July 2008; accepted 15 September 2008. published online 17 November 2008.

Abstract

Objective

To assess the use of tunica vaginalis graft plus onlay preputial island flap in urethral reconstructive surgery in rabbits through histopathology.

Material and methods

We developed an experimental model of urethroplasty that resembles one-stage complex hypospadias surgery with divided urethral plate. The tunica vaginalis graft is dorsally placed to recreate the urethral plate and the internal preputial island flap is placed onlay to complete the urethroplasty. Sixteen animals were divided into four equal groups and sacrificed at 2, 4, 8 and 12 weeks after surgery, the penis being sent for histopathological evaluation.

Results

There were no deaths related to the procedure or wound breakdown; all rabbits voided spontaneously after surgery. Two urethrocutaneous fistulae were found. Microscopically, good tissue integration was observed, the tunica vaginalis mesothelium was gradually replaced by a more stratified epithelial lining, similar to the urothelial lining of the native urethra. The stratified squamous non-keratinized lining of the internal preputial island flap also changed into a thinner epithelial lining with only 4–5 cell layers. Two urethral diverticula were found.

Conclusion

A tunica vaginalis graft placed dorsally plus an onlay internal preputial island flap was shown to be a successful technique for urethroplasty in an animal model.

Keywords: Urethra, Rabbits, Tunica vaginalis, Surgical flaps