What are varicose veins primarily characterized by?

Varicose veins are primarily characterized by dilated, tortuous superficial veins. This condition arises when the valves within the veins become weakened or damaged, leading to improper blood flow and pooling of blood. As a result, the veins become enlarged and twisted in appearance. These changes often occur in the superficial venous system of the legs, where the increased venous pressure leads to the characteristic distention observable in varicose veins.

The appearance of varicose veins can be visually distinct, often presenting as swollen, dark-blue or purple veins that can be easily seen just under the skin. This condition is typically associated with discomfort, such as aching, heaviness, or fatigue in the legs, particularly after prolonged standing or sitting.

Given this understanding, the other options do not accurately represent the defining features of varicose veins. For instance, constricted, straight veins refer to a normal or healthy state of veins, while the presence of clots pertains to deep vein thrombosis rather than the structural abnormalities seen in varicose veins. Similarly, inflamed veins might suggest conditions like superficial thrombophlebitis but do not encapsulate the characteristic features of varicosity.