Varicose veins are a manifestation of superficial venous insufficiency (link on CVI is already there)
Varicose veins are abnormally dilated superficial veins that could be seen just beneath the skin. They might be bluish or purplish in color and have a twisted, tortuous or even knotty appearance.
Varicose veins are a relativel common condition. It is estimated that approximately 30% of people will develop it in their lifetime. Incidence increases with an advancing age , and women are more likely to suffer. Statisticaldata suggest that after the age of fifty about 70% of women have some degree of venous insufficiency in general and varicose veins in particular.
There are several factors that contribute to developing varicose veins, heredity being the main one. Others are:

• pregnancy (odds increasing with each consecutive one),
• occupation requiring prolonged sitting or standing,
• obesity

When the pressure inside the veins abnormally increases, it causes the venous wall to distend and bulge out, thus causing visible varicosities to appear. (This could be postponed/prevented, but) Unfortunately, once there, the process is irreversible and damage to the vein wall is permanent. Vein simply ceases to actively participate in circulation .Along with purely cosmetic issues other problems might arise, such as

• pain
• itching
• feeling of heaviness
• ankle swelling
• skin changes (from dryness and excessive pigmentation to ulcers)
• restless leg syndrome

Thrombosis of the varicose vein is rare, but possible complication.