Spider veins themselves are just the tip of the iceberg. Two even bigger culprits lurk beneath the skin’s surface. One of these villians goes by the name of “incompetent reticular vein.”
That’s the standard medical term for a larger vein that lies just below the surface of the skin. Many doctors refer to them as feeding green veins. That’s because in fair-skinned patients they’re greenish-blue in color and they “feed” blood at excessive pressures into clusters of spider veins. Other physicians refer to them as blue-green veins or root veins.(every villain must have an alias)
The other culprit is the incompetent perforator vein. Perforator veins are short connecting blood vessels that carry blood from your superficial vein system inward to your deep vein system. Your deep veins then transport the blood briskly up your legs and back into your heart and lungs for replenishment with oxygen.
A valve with each perforator vein allows blood to flow in only one direction: from the superficial veins to the deep veins. But if this valve becomes defective and leaks (i.e. the perforator vein becomes incompetent), blood begins to flow backwards from the deep veins to the superficial veins.