Comparative Study Between Porcine Small Intestinal Submucosa and Buccal Mucosa in a Partial Urethra Substitution in Rabbits

Purpose: Several urethral conditions may require tissue substitution. One collagen-base biomaterial that recently emerged as an option is small intestinal submucosa (SIS). The aim of this study was to compare the results of SIS and buccal mucosa for urethral substitution in rabbits.Materials and Methods: Thirty-six North Folk male rabbits were randomized into three groups. In all animals, a 10 x 5 mm urethral segment was excised, and the urethral defect was repaired using a one-layer SIS patch (group I [GI]); four-layer SIS (group II [GII]); or buccal mucosa (group III [GIII]). Urethrography was performed preoperatively and after 12 weeks. After sacrifice, graft retraction was objectively measured using Scion Image (R) computer analysis and by calculation of ellipse area. The grade of fibrosis, inflammatory reaction, vascular/epithelial regeneration, and collagen III/I ratio were analyzed by hematoxylin/eosin and Picrosirius red staining.Results: Urethrography confirmed a wide urethral caliber without any signs of strictures after surgery. Urethral fistulae was diagnosed in 8.3% of cases (1 animal each group). Average graft shrinkage was 55.2% in GI; 44.2% in GII; and 57.2% in GIII (p < 0.05). The intensity of chronic inflammation, fibrosis, epithelium regeneration, and neovascularization was similar in all groups (p > 0.05). Collagen III/I ratio was higher in GII (GI: 119.6; GII: 257.2 and GIII: 115.0); p < 0.01.Conclusions: The four-layer SIS is more advantageous than the one-layer SIS and buccal mucosa for urethral substitution in rabbits.

Long-term outcome of penile fracture treatment

Objectives: Penile fracture is a rare injury, usually resulting from direct trauma to the erect penis during sexual intercourse. Our goal was to evaluate the best diagnostic methods and the late complications following surgical treatment of penile fracture. Material and Methods: We studied retrospectively 11 patients with penile fracture in a period of 10 years (1985-1995). Results: In 55% of the cases, the injury occurred during sexual intercourse. All patients presented with a very suggestive clinical picture (pain, detumescence and hematoma) and only 2 were submitted to further investigation (ultrasonography) to confirm the diagnosis. Only one patient had urethral bleeding and therefore was submitted to retrograde urethrogram, which confirmed urethral injury. All patients were treated by immediate surgery, through a circular subcoronal incision and degloving of the penis to allow a thorough exploration. All patients had a tunica albuginea tear that was promptly repaired, and 2 patients (18%) had associated urethral injury (one had no symptoms) that was also repaired. All patients did very well after surgery and only one had a mild curvature, which did not hinder intercourse during follow-up (18 months). Conclusions: Penile fracture has very typical clinical signs and, therefore, further investigation is usually unnecessary. Early surgical treatment is associated with a low incidence of late complications.

Colágeno acelular e mucosa oral na substituição parcial da uretra: estudo comparativo em coelhos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)