Influence of interstitial fibrosis on spermatogenesis after vasectomy and vasovasostomy

This study focused on the testicular interstitial fibrosis after vasectomy and the intraseminiferous status [i.e., Johnsen's score, proliferative cell nuclear antigen (PCNA) expression] following vasectomy reversal. Testicular biopsy specimens from 21 consecutive men were obtained at vasovasostomy. Percent of interstitial fibrosis was determined quantitatively by NIH-image after Masson Trichrome staining. PCNA-labeling index (LI) was calculated on each testis. The associations between the obstructive interval and each parameter were examined. These parameters were also analyzed on whether patency or pregnancy was achieved or not. Significant decrease in PCNA-LI and increase in interstitial fibrosis were observed along with the obstructive interval (p <0.0001, p = 0.0005, respectively). Interstitial fibrosis of the patients without patency/fertility was significantly greater than that of the patients with patency/fertility (47.5%/39.0% versus 33.4%/32.3%, p = 0.02/0.04, respectively). PCNA-LI and Johnsen's score did not predict the treatment outcome. Interstistial fibrosis, but not the extent of germ cell differentiation or DNA synthesis, reflects the treatment outcome after vasectomy reversal. Interstistial fibrosis contributes to the irreversible damage of vasectomized testes.