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Head CT Angiography

A head CT Angiography is a specialized Neuro CT scan which involves fast CT imaging while simultaneously injecting IV contrast into a vein in your arm. This allows for visualization of specific vascular anatomy of the organs in your body. It may be used to evaluate vessels or for surgical planning.

Preparation for Your Exam

Please do not eat solid foods for at least three hours before your test. You may; however, drink clear liquids during this time as well as take your usual medications.

For your exam you will be required to receive IV contrast (dye). IV contrast is an iodine based solution that is injected into your veins and appears very bright (white) on a CT image. This contrast allows for enhanced visualization of the blood vessels in your head. IV contrast is filtered from your blood by your kidneys and will be passed, unnoticed, from your body in your urine.

It is important that you inform the technologist before your exam if:

  • You have had IV contrast before
  • You have asthma
  • You are allergic to any foods or medications
  • You may be pregnant or breastfeeding
  • You are diabetic and taking Glucophage (metformin)

During The Exam

When you are taken into the CT room you will be asked to lye on a CT table. Like all CT exams it is very important that you hold very still for the duration of the study. This table will move in and out of the CT scanner (a large donut-shaped machine that is open on both ends) while acquiring images.

How long will it take?

This is different for everyone; however, on average, it should take 10-20 minutes from the time you enter the room.

After The Exam

You may resume your normal daily routine after your exam. Because you will receive IV contrast for your exam, it will be important that you increase your fluid intake to help clear the material from your system.

Getting Your Results

The CT examination will first be viewed by a radiologist who will send a report to your doctor. Your doctor should have access to your exam results within 24 hours.