What Are Varicose Veins and their Causes?

When vein valves fail, reflux or reversal of flow occurs. This condition leads to increased internal pressure on the vein wall and pooling of blood below the valve, resulting in dilation or bulging that is visible through the skin. Varicose veins range in size from large, protuberant veins to smaller blue veins called reticular veins and finally to tiny web-like veins called spider veins. The typical distribution of spider veins occurs in the ankles, lower inner thighs and the front and sides of the thighs.

Reticular veins are most often noted in the outer thighs, extending into the backs of the thighs and knees. Varicose veins can usually be traced from the upper inside of the thigh, sometimes branching extensively into the calves, ankles and even into the foot. Varicose veins are often regarded as a cosmetic nuisance, but in reality, they also present potentially serious health problems that can be corrected with proper therapy. The larger varicosities put the patient at risk for phlebitis (painful inflammation), brownish discoloration of the skin, dermatitis and, in advanced cases, clot formation with ulceration and permanent scarring. Reticular veins may or may not develop into severe health hazards, but they are often accompanied by significant symptoms of local tenderness or burning and itching.

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