The body’s venous system is divided into two parts: the deep venous system, which transports blood through vital organs, and the superficial venous system. The latter consists of thin vessels that tend to dilate, especially when the deep veins do not efficiently circulate blood. These dilated veins become visible and take on a bluish, red, or purple hue. They typically measure between 0.1 mm and 3 mm in diameter.
Smaller and more superficial than varicose veins, spider veins usually appear on the legs and are associated with discomfort. They can weaken the skin, causing itching and, in severe cases, ulcers. Aesthetically, spider veins are highly visible and can be a source of concern for many individuals.