A varicocele is a usually painless swelling of the scrotum involving dilated spermatic veins (pampiniform plexus) that form a soft scrotal mass, most often on the left side. Thought to be the result of venous pressure, varicoceles are typically asymptomatic but may present with scrotal discomfort and heaviness. Classically, varicoceles are described as a "bag of worms" on palpation.

Rarely occurring in children, onset is typically at puberty and may even be diagnosed incidentally during evaluation for infertility. Varicoceles are common and occur in approximately 15% of adolescent males. When fertility is of concern, or in recurrent varicoceles, treatment may involve surgical ligation, embolization, or transfemoral catheterization and ablation of the spermatic vein.