Duplex ultrasounds are a type of medical test that vein doctors use to evaluate the health of veins and the flow of blood through those veins. Vascular surgeons often use duplex ultrasounds to understand the underlying cause of varicose veins and to determine whether varicose vein treatment is appropriate. If you have varicose veins, your doctor may recommend a duplex ultrasound before you decide which type of vein treatment is right for you.

How Duplex Ultrasound Works

  • Doctors perform ultrasounds by applying special ultrasound gel on the skin then placing an ultrasound probe over the affected area. The probe emits high-frequency sound waves through the gel and into the body; these sound waves bounce back after hitting certain feature in the body. A transducer in the probe collects the sounds waves that bounce back then sends them to a computer, which uses the sound waves to create an image.
  • There are several types of ultrasound and each uses sound waves to detect anatomical structures. Standard ultrasounds produce images that are gray-scale, which means the images look like a black and white photograph. Standard gray-scale ultrasound is helpful for discerning features, such as veins and arteries. Standard ultrasounds do not help the doctor assess motion, however, like blood flowing through the veins.
  • Doppler ultrasound can assess motion by bouncing the sound waves off the red blood cells flowing through veins. The computer interprets information and presents a color flow display or picture.
  • Doppler technology helps doctors assess the health of blood vessels and evaluate blood flow to a limb or organ. This technology can help doctors determine if a blood clot or other problem is obstructing the flow of blood.
  • Duplex ultrasound machines overlays the images produced by Doppler ultrasound on top of the images produced by gray-scale ultrasound on a single screen. This helps give doctors a complete view of the health of your veins and the blood flow within it.
  • Doppler ultrasound is just as safe as gray-scale ultrasound. Neither procedure exposes the patient to dangerous ionizing radiation, as used in x-rays.
  • If you have varicose veins and wonder if you should undergo duplex ultrasound, make an appointment with your local vein clinic.