



If I have it right (yes, my memory) this is the beginning of a condition known as Varicocele. Here is some brief detail on that:
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The scrotum is a skin-covered sac that holds your testicles. It also contains the arteries and veins that deliver blood to the reproductive glands. A vein abnormality in the scrotum may result in a varicocele.A varicocele is an enlargement of the veins within the scrotum.
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There is another possibility for this - but you would be best to get a medical professional, such as a Urologist to check this for you