A venous duplex scan is a painless test that uses ultrasound waves to examine how veins are returning blood to the heart, states MemorialCare Health System. The test takes images of the inside of the veins to search for blood clots or abnormalities in the veins.
A venous duplex ultrasound is most often used to examine the legs for blood clots or deep vein thrombosis, according to RadiologyInfo.org. Blood clots are particularly important because if a blood clot breaks off and travels into the lungs, it can cause a serious condition called a pulmonary embolism. The test is helpful because if a clot from the leg is found early enough, the right treatment may stop it before it has an opportunity to travel to the lungs.
Other uses for a venous duplex scan are to establish the cause for long-term leg swelling and to help a doctor determine the best way to treat varicose veins, indicates RadiologyInfo.org. It may also be used by medical professionals as a visual aide to help accurately insert a catheter or needle into a vein, or when a doctor intends to use part of a healthy vein to surgically bypass another that is damaged or blocked.