Influence of mesh materials on the integrity of the vas deferens following Lichtenstein hernioplasty: an experimental model.

BACKGROUND

The utilization of mesh reinforcement of the inguinal area with polypropylene mesh has increased drastically over the last decade. Infertility due to obstructive azoospermia is a rare but serious complication following inguinal hernia repair, especially in young patients. The aim of this study was to evaluate the effect of different mesh structures on integrity of the vas deferens.

MATERIALS AND

METHODS

Twenty male Chinchilla rabbits were used. The spermatic cord was dissected free and a Lichtenstein repair was performed with a low-weight polypropylene mesh (UltraPro) and a heavy-weight polypropylene mesh (Prolene) on the contralateral side. A vasography was performed after six months in order to investigate obstructions of the vas deferens. Light microscopy of the mesh host tissue interface was also performed and the foreign body reaction analyzed. Spermatogenesis was evaluated using the Johnsen score.

RESULTS

Vasography revealed relevant obstructions (>75% of lumen diameter) located at the mesh margins (50% of Prolene and 22.2% of UltraPro mesh samples). Microscopic investigation of the mesh-host tissue interface showed typical formation of foreign body granulomas. The diameters of the foreign body granulomas were significantly reduced in the UltraPro mesh group (41.7 +/- 5.5 microm) compared to the Prolene mesh group (48.7 +/- 7.7 microm). Upon investigating the percentages of apoptotic (TUNEL) and proliferating (Ki67) cells, no significant differences were found. Following Prolene mesh implantation, a mean Johnsen score of 9.1 +/- 1.2 was estimated, which was not significantly different from the UltraPro mesh samples (8.9 +/- 1.4, P > 0.05).

CONCLUSIONS

If a mesh material is needed for inguinal hernia repair in young patients, the use of modern low-weight large porous and elastic samples appears to have a beneficial effect on integrity of the vas deferens.