Exams and Treatments



Lower Extremity CT Scan with contrast agent


A lower extremity CT scan uses a series of X-rays to diagnose vascular pathologies in the legs and abdomen. This exam may also be used to detect some bone pathologies in this region. In this case, a contrast agent is injected intravenously to highlight the area being examined.


30 to 45 minutes

  • A blood test to evaluate the kidneys' effectiveness at eliminating the contrast agent is required for this exam.
  • You should plan to arrive 2 hours before the appointment time.
  • During the appointment, you should advise staff whether you have allergies or are diabetic, as you will receive additional instructions.
  • For women of childbearing age, it is important to advise the technologist if you might be pregnant, as X-rays are harmful to the fetus.
  • Breastfeeding women must stop breastfeeding for a period of 48 hours.
  • You must be in a fasting state for at least 3 hours before the exam.
  • Remove earrings, hearing aids, eyebrow piercings, hair clips and wigs.

A medical imaging technologist will position you on your back. An IV catheter is inserted into a vein so that the contrast agent can be injected. Your arms will then be positioned above your head. The injection of the contrast agent can cause a sensation of warmth, a false need to urinate, or a metallic taste in your mouth. These effects only last a few seconds and then immediately disappear. Shields are then placed over the genitals and breasts (for women) to prevent these areas from being exposed unnecessarily to radiation. You will be given instructions about when to hold your breath as the images are acquired.

Follow-up and side effects 
  • A radiologist will analyze the exam and send the report to your treating physician. An allergic reaction may occur, but the team is prepared to quickly react to this possibility.
  • You will have to drink a lot of water to eliminate the contrast agent.
  • For diabetics, a second blood test may be required 48 hours after the exam. These patients will receive additional instructions about restarting their medication.
Medical Imaging Department