A new material to prevent urethral damage after implantation of artificial devices: an experimental study

ABSTRACT Objective To validate the application of the bacterial cellulose (BC) membrane as a protecting barrier to the urethra. Materials and Methods Forty female Wistar rats (four groups of 10): Group 1 (sham), the urethra was dissected as in previous groups and nothing applied around; Group 2, received a 0.7cm strip of the BC applied around the urethra just below the bladder neck; Group 3, received a silicon strip with the same dimensions as in group 2; Group 4, had a combination of 2 and 3 groups being the silicon strip applied over the cellulosic material. Half of the animals in each group were killed at 4 and 8 months. Bladder and urethra were fixed in formalin for histological analysis. Results Inflammatory infiltrates were more intense at 4 months at lymphonodes (80% Grade 2), statistically different in the group 2 compared with groups 1 (p=0.0044) and 3 (p=0.0154). At 8 months, all samples were classified as grade 1 indicating a less intense inflammatory reaction in all groups. In group 2, at 8 months, there was a reduction in epithelial thickness (30±1μm) when com-pared to groups 1 (p=0.0001) and 3 (p<0.0001). Angiogenesis was present in groups 2 and 4 and absent in group 3. In BC implant, at 4 and 8 months, it was significant when comparing groups 4 with 1 (p=0.0159). Conclusion BC membrane was well integrated to the urethral wall promoting tissue remodeling and strengthening based on morphometric and histological results and may be a future option to prevent urethral damage.

Dartos flap coverage of the neourethra following repair for primary hypospadias, reoperative hypospadias and urethrocutaneous fistulas: it is a safe approach / Emprego de um retalho pediculado do músculo dartos para cobertura da neouretra na cirurgia primária de hipospádias, reoperações de hipospádias e correção de fístulas uretrocutâneas

Purpose: Urethrocutaneous fistula and neourethral dehiscence are frequently seen complications of hypospadias surgery requiring reoperation. In this study we report the experience of one surgeon with dartos flap coverage in primary hypospadias, reoperative hypospadias and urethrocutaneous fistulas repair. Methods: A total of 23 patients underwent hypospadias and urethrocutaneous fistulas repair from January 2006 to May 2009. Fourteen patients were operated on for primary hypospadias repair at our institution and 9 patients were admitted for hypospadias complications such as failed hypospadias repair and urethrocutaneous fistula. In all the patients, the dartos flap was dissected and transposed to cover the neourethra. Operative results were recorded. Results: The primary surgical procedure was a one-stage repair in 61 percent (n = 14); tubularised incised plate (TIP) urethroplasty in 43 percent (n = 6) and a Mathieu procedure in 57 percent (n = 8). Urethrocutaneous fistulas complicating the previous initial hypospadias repair were anterior in 33 percent (n = 2), middle in 33 percent (n = 2) and proximal in 33 percent (n = 2). Repair of the fistula was successful on the first attempt in all patients. The reason for redo surgery in 3 patients was complete dehiscence and the patients had distal shaft hypospadias. COconclusion: Dartos flap coverage of the neourethra seems to be an effective method of reducing the fistulous complication rate following primary and secondary hypospadias repair.

Objetivo: Fístulas uretrocutâneas e deiscências são complicações frequentes na cirurgia das hipospádias necessitando reoperações. Este estudo é baseado na experiência pessoal de um cirurgião utilizando um retalho pediculado do músculo dartos para cobertura da neouretra na correção primária de hipospádias, reoperações de hipospádias e correção de fístulas uretrocutâneas. Métodos: Vinte e três pacientes foram operados sendo 14 submetidos a cirurgia primária de hipospádia e 9 a reoperações por insucesso da correção primária ou por fístulas uretrocutâneas. Em todos os pacientes, um retalho pediculado do músculo dartos foi mobilizado e utilizado para recobrir a neouretra. Resultados: Para a cirurgia primária da hipospádia foi utilizada técnica de correção em um só tempo (n=14): uretroplastia tubularizada com incisão da placa (TIP) em 43 por cento (n=6) e técnica de Mathieu em 57 por cento (n=8). As fístulas uretrocutâneas resultantes de correções primárias anteriores eram de localização anterior em 33 por cento (n=2), média em 33 por cento (n=2) e proximal em 33 por cento (n=2). A correção das fístulas uretrocutâneas resultou em sucesso em todos os pacientes. Três pacientes necessitaram de reoperação por deiscência completa e em todos a hipospádia era distal. Conclusões: O emprego do retalho pediculado do músculo dartos para recobrir a neouretra é um método eficaz que reduz a incidência de fístulas em cirurgias primárias e nas reoperações de hipospádias.