A polymeric mini-stent designed to facilitate the vasectomy reversal operation. A rabbit model study

Vasectomy has become popular since it is the safest surgical method for contraception. It is known that approximately 6% of the men that undergo vasectomy will seek reversal (vasovasostomy). This operation is, however, technically demanding and relatively time-consuming. This study was based on the hypothesis that a polymeric mini-stent can facilitate and accelerate vasovasostomies. A mini-stent was manufactured out of a crosslinked hydrogel biomaterial, which was synthesized from N-vinyl-pyrrolidinone (NVP), n-butylmethacrylate, and (triethyleneglycol) dimethacrylate. The device was tested with 28 rabbits, which were divided over two equal groups. In one group, the vasa deferentia were dissected and reanastomosed via microsurgical one-layer technique (end-to-end group). In the other group, the vasa deferentia were dissected and reattached through implantation of the mini-stent. Sperm counts revealed 100% patency in both groups, i.e. all vasovasostomies were successful. It was experienced that the operation was easier and faster in the case of the mini-stent, probably since the mini-stent keeps the lumens of both vas ends exactly in line during suturing. This study demonstrates the feasibility of the mini-stent. Further work is necessary to evaluate the utility of this approach for clinical vasovasostomies.