Histologic evaluation of spermatic veins in patients with varicocele

Background: Information concerning varicocele is limited in spite of its clinical importance. This study intends to clarify anatomical features of varicocele. Methods: Spermatic veins were obtained from varicocele patients at surgery. Areas of two distinct portions (extracellular matrix and smooth muscle) were measured by a micro computer imaging device image analysis system on histologic slides with Masson trichrome stain. In addition, we evaluated the shape and arrangement of the smooth muscle fibers by a scanning electron microscope (SEM). Results: Masson trichrome stain revealed that grade of varicocele partly correlated with thickness of the wall and with amount of the smooth muscle fibers. In the patients with grade 3 varicocele, SEM examination showed marked hypertrophy of longitudinal smooth muscle fibers, which were discriminated clearly from the inner circular fibers. Conclusions: This study indicated that morphological changes occurred in the muscle layers of varicoceles in the worst grade of varicocele. These structural changes which result from abnormal venous blood circulation may cause development of varicocele, resulting in male infertility.