Theodorescu D, Balcom A, Smith C R, McLorie G A, Churchill B M, Khoury A E
Department of Surgery, The Hospital for Sick Children, University of Toronto, Ontario, Canada.
J Urol. 1998 May;159(5):1708-11. doi: 10.1097/00005392-199805000-00098.
Residual urethral defects after failed hypospadias surgery present difficulties in reconstruction. In these situations, repair using vascularized tissue flaps remains ideal, yet challenging. In order to offer more surgical alternatives in these cases, the use of vascularized tunica vaginalis flaps as urethral replacements has recently been established in an animal model. We undertook the following studies to further define the role of tunica vaginalis in urethral reconstruction.
A vascularized flap of tunica vaginalis was used to replace an experimentally created 25-30 mm. gap in the anterior urethra of 26 rabbits, either as an onlay or tube flap. A control group consisting of 7 animals underwent only a segmental anterior urethral resection and primary re-anastomosis.
Satisfactory urethral healing occurred in all control animals that survived the procedure. All 8 animals which had tunica vaginalis tube flap reconstruction underwent contracture of the neourethra probably secondary to the presence of striated cremasteric muscle elements brought with the tunica during mobilization. All 16 animals available for long term study in the onlay flap group had excellent flap viability and 100% urethral patency rates. The mesothelial lining of the tunica was seen to be replaced by a stratified epithelial lining similar to the urothelial lining of the native urethra.
The tunica vaginalis is a viable alternative to other tissues presently used for urethral replacement and can be used successfully as a vascularized onlay flap.
尿道下裂手术失败后残留的尿道缺损给重建带来困难。在这些情况下，使用带血管蒂组织瓣进行修复仍然是理想的选择，但具有挑战性。为了在这些病例中提供更多的手术选择，最近在动物模型中确立了使用带血管蒂的睾丸鞘膜瓣替代尿道。我们进行了以下研究以进一步明确睾丸鞘膜在尿道重建中的作用。
使用带血管蒂的睾丸鞘膜瓣替代26只兔子实验性造成的25 - 30毫米前尿道缺损，采用覆盖法或管状瓣法。对照组由7只动物组成，仅接受节段性前尿道切除及一期重新吻合术。
所有在手术中存活下来的对照动物尿道愈合良好。所有8只接受睾丸鞘膜管状瓣重建的动物新尿道均发生挛缩，可能是由于在游离过程中睾丸鞘膜携带的横纹状提睾肌成分所致。覆盖法瓣组所有16只可供长期研究的动物瓣存活良好，尿道通畅率达100%。可见睾丸鞘膜的间皮衬里被类似于天然尿道尿路上皮衬里的复层上皮衬里所取代。
睾丸鞘膜是目前用于尿道替代的其他组织的可行替代物，可成功用作带血管蒂的覆盖法瓣。
