What are perforator veins?
Perforating veins, commonly called perforators, are veins that take blood from the superficial veins just under the skin, through the muscle, and into the deep veins. Once in the deep veins, blood can be pumped to the heart by the muscle pump.
The reason they are called 'perforators' (or 'perforating veins') is that they "perforate" across the connective tissue that surrounds the muscle - called "fascia".
There are approximately 150 perforating veins (or 'perforators') in each leg. In normal function, blood always flows from the outside of the leg to the inside of the leg and then up to the heart.
If the perforating vein becomes "incompetent" (due to the valves in the vein failing), blood will flow the opposite way during muscle contraction. This can then cause clinical problems. In this situation, the veins are correctly called 'incompetent perforating veins' or "IPVs" for short. However as normal perforators are very small, and are not often seen even on ultrasound scans, we tend to only see perforating veins when they become incompetent. Therefore when doctors and nurses talk about "perforators" they often mean incompetent perforating veins (IPVs).