Julie Fallon, of Ardgowan School, asks :-

Why do some people have bulging varicose veins?

John Morton, a vascular surgeon at Christchurch Hospital, responds. :-

Varicose veins in the legs are very common. In carrying blood from the lower limbs back towards the heart, gravity has to be overcome. Normally this is achieved by the muscles in the limbs providing a pumping action, and valves in the veins preventing blood refluxing back down the veins when the muscles relax.

Varicose veins sometimes run in families. These families do not seem to have enough valves in their veins. Later in life the valves can be destroyed by clotting in the veins. When the valves are absent, or fail for whatever reason, the vein wall is subjected to high pressure which causes it to dilate and become elongated - "bulging varicose veins".