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What is Varicocele and explain in detail?
A varicocele is an abnormal enlargement of the pampiniform venous plexus in the scrotum. This plexus of veins drains blood from the testicles back to the heart. The vessels originate in the abdomen and course down through the inguinal canal as part of the spermatic cord on their way to the testis. Varicoceles occur in around 15% to 20% of all men. The incidence of varicocele increase with age.

Signs and symptoms
Varicocele might be noticed as soft lumps, usually above the testicle and mostly on the left side of the scrotum. Right-sided and bilateral varicocele does also occur. Men with varicocele can feel symptoms of pain or heaviness in their scrotum. Large varicoceles present as plexus of veins and may be described as "bag of worms". Varicocele is sometimes discovered when investigating the cause of male infertility.

Cause
There are three main theories as to the anatomical cause; the first has to do with the geometry of the veins, wherein the vein on the left side connects to the larger outflowing vein at a right angle, which tends to fail; the second is that valves that are supposed to prevent backflow fail (venous insufficiency); the third is due to excessive pressure in upstream arteries, created by nutcracker syndrome.

Pathophysiology
Often the greatest concern with respect to varicocele is its effect on male fertility. The relationship between varicocele and infertility is unclear. Some men with the condition are fertile, some have sperm that are normal in shape and move normally but are compromised in function, and some have sperm with abnormal shapes or that do not move well