Varicocele
A varicocele is when veins become enlarged inside your scrotum (the pouch of skin that holds your testicles). These veins are called the pampiniform plexus. It is like getting a varicose vein in your leg. Most of the time, varicoceles cause no problems and are harmless.
What are the causes of Varicocele?
Many causes of varicoceles have been offered. The valves in the veins may not work well (or may be missing). If blood flow is sluggish, blood may pool in the veins. If blood flows backwards or pools in the veins, that can cause them to swell. Rarely, swollen lymph nodes or other masses behind the belly block blood flow. This can lead to sudden swelling of the scrotal veins. This is often painful.