Varicocele is associated with an increase of connective tissue of the pampiniform plexus vein wall

Abstract

Objective: The purpose of this study is to describe the normal structure of spermatic vein wall and the morphological alterations in patients with grades 1-3 varicocele.

Methods: We dissected and analyzed a 2-3 cm tract of a pampiniform plexus vein of 30 patients undergoing antegrade scrotal sclerotherapy for left varicocele and of 13 consecutive patients undergoing radical orchidectomy for left testis cancer. The histological and morphological examination was performed with hematoxylin-eosin and Azan-Mallory staining through a computer image analysis approach. Vasa vasorum number was evaluated through the anti-CD31 monoclonal antibody.

Results: In normal veins, the tunica media had a circular smooth muscle layer, the tunica adventitia a longitudinal one; oblique fibers connected the longitudinal with the circular layer. In grade 1 varicocele, we found an increase in the connective tissue of the adventitia (39 vs. 1%, P < 0.001) and of the tunica media (13 vs. 0.5%, P = 0.001) and a decrease of oblique fibers. In grade 2 varicocele, the adventitia and media showed greater connective tissue (40 and 15%, P < 0.001). In grade 3 varicocele, adventitia and media showed a further increase in connective tissue (52 and 28%, respectively, <0.001). No oblique fibers were found in these veins. Vasa vasorum were decreased in number in patients with grades I and II varicocele, and were absent in patients with grade III varicocele.

Conclusion: The wall of pampiniform plexus veins is a complex structure. Varicocele induces a decrease of vasa vasorum number, a fibrotic degeneration of the adventitia and media, and a decrease of the oblique running fibers.