An experimental study of colonic mucosal graft for urethral reconstruction

结肠粘膜重建尿道的实验研究(英文)

OBJECTIVE: To investigate the possibility of urethral reconstruction with a free colonic mucosal graft. METHODS: Ten female dogs underwent a procedure in which the urethral mucosa was totally removed and replaced with a free graft of colic mucosa. A urodynamic study was performed before the operation and sacrifice. The dogs were sacrificed 8 to 16 weeks after the operation for histological examination of the urethra. RESULTS: Urethral stricture developed in 1 dog. The results of urody namic studies showed that the difference in maximum urethral pressure between pre-operation and pre-sacrifice in the remaining 9 dogs was not of significance (P > 0.05). Histological examination revealed that the colonic free mucosa survived inside the urethral lumen of the 9 dogs. Plicae surface and unilaminar cylindric epithelium of the colonic mucosa was observed in dogs sacrificed 8 weeks after the operation. Plicae surface and unilaminar cylindric epithelium of the colonic mucosa was not observed and metaplastic transitional epithelium covered a large proportion of the urethral mucosa in dogs sacrificed 12 weeks after the operation. CONCLUSIONS: Urethral mucosa can be replaced by colonic mucosa without damaging the continence mechanism in female dogs. This technique is useful when local or preputial skin and buccal or bladder mucosa are not available.

目的 探索结肠粘膜重建尿道的可行性。方法 10条雌性狗在全麻下行游离结肠粘膜替代尿道粘膜的手术。在手术及处死前分别进行尿动力学检查。术后 8～ 16周将狗处死 ,其尿道作病理检查。结果 1条狗发生尿道狭窄 ,余 9条狗的尿动力学检查提示 :手术前与处死前的最大尿道压之间差异无显著意义(P >0 0 5 )。 10条狗的尿道病理组织学检查提示 :移植于尿道的结肠粘膜全部成活 ,术后 8周处死的狗显示结肠粘膜表面皱襞存在 ,被覆单层低拄状的吸收上皮和杯状细胞 ;术后 12周后处死的狗显示结肠粘膜表面皱襞 ,被覆的单层吸收上皮和杯状细胞消失 ,尿道粘膜大部分已被化生为假多层的移行上皮复盖。结论 结肠粘膜能替代尿道粘膜 ,尿道纵行切开对雌性狗的括约功能影响不大。