Medical Imaging

Ultrasound > Exams & Procedures > Lower Leg Venous

This ultrasound examination looks at the veins of the lower leg, from the groin to the back of the knee, that runs on the inside of the thighs. Veins run from your feet to your heart. Therefore, if a clot or blockage were present in the calf, this would prevent any blood flowing up to the thigh. This is the reason for examining the leg above the calf. A Doppler study is used to examine these veins. Any areas of blockage or clot will be detected in this examination. Colour Doppler displays colour to show the direction of flow. Pulsed Doppler allows you to listen for the characteristic sounds that differentiate arteries and veins make. It can also produce a graph displaying the speed and direction of blood flow.

  • The procedure takes about 20 minutes to one hour depending on whether one leg or both legs being examined.
  • No preparation is required.
  • You will be asked to lie down on a table with your abdomen uncovered. An odourless and water-soluble gel will be put on your skin by the ultrasound technologist. This helps to transmit the sound waves and allows easy movement of the probe or transducer over the skin.
  • The technologist will move the probe along the skin, taking pictures of the vein at different levels.
  • Three tests are done to exclude any blood clots:
    1. The technologist will begin by pressing down on the vein along the whole length of the thigh. If the vein collapses when compressed, it indicates that there is no blockage preventing the vein from collapsing.
    2. The technologist will then listen and watch for the blood flow within the vein.
    3. While watching the graphic display of blood flowing, the technologist will give you a gentle squeeze on the calf to force a gush of blood up the vein.
  • The combination of these three tests gives a 10% exclusion rate of any clot. The technologist will then leave the room once all the pictures are taken in order to develop the images and show them to the radiologist before letting you leave.

Does it hurt?

No.

When will I get my results?

If you are seeing your doctor immediately after your ultrasound appointment, a hand written report preliminary will be given to you. If you are not seeing your doctor following the ultrasound test, a final report will be mailed to your doctor within seven days.