Varicocele

A varicocele is a dilation of the pampiniform venous plexus within the spermatic cord, analogous to varicose veins in the legs. Varicoceles occur in 15% of the general male population and in 35-40% of men evaluated for infertility, making it the most common correctable cause of male infertility. The left side is affected in approximately 85-90% of cases because the left gonadal vein drains into the left renal vein at a right angle (versus the right gonadal vein draining directly into the IVC at an acute angle), creating higher hydrostatic pressure. The dilated veins create a countercurrent heat exchange defect, raising intrascrotal temperature by 1-2°C above the optimal 34°C for spermatogenesis. Additional mechanisms of fertility impairment include reflux of adrenal metabolites, oxidative stress, and Leydig cell dysfunction. On examination, varicoceles classically feel like a 'bag of worms' above the testis and are more prominent when standing and performing Valsalva maneuver.