Deep Veins are are located deep in the leg between muscle and fascia (tough fibrous tissue). They are responsible for returning 90-95% of the venous blood back to the heart.
Perforating Veins link the deep and superficial veins together.
Superficial Veins are usually affected by varicosities because they have little external support like the deep veins. These veins are visible from the skin when varicose. They drain the blood from the skin and are also responsible for blood storage. When these veins become varicose they can appear engorged and distended. This group also includes reticular veins and spider veins. Reticular veins are small blue veins often seen through the skin. These are often the cause of spider veins, which are the tiniest blue purple veins seen in the skin.