CT Angiography

CT angiography is a new technique that allows imaging of arteries and veins, replacing older, catheter based techniques of imaging these same structures. Previously, in order to image an artery (in the heart, or brain, for instance), a catheter had to be guided through the body, usually via a catheterization site in the groin, until its tip was in the artery of interest. Then, contrast was injected, and x-rays were taken, resulting in an “angiogram”. This technique was invasive, and not without risk.

With modern CT machines (multi-detector CT scanners, like we have at MRA), we can achieve detailed evaluation of arteries non-invasively. Briefly, contrast is injected into a vein in your arm (this is the same contrast and site of injection for any routine CT scan). We then time the exam to start when the contrast has circulated through your body, and is in the artery of interest (ie, heart, renal arteries, arteries of the brain). With thin section imaging, and 3D processing now available on high tech computers, an angiogram is obtained.

This technique has gained acceptance in the medical community, and offers excellent, non-invasive images of arteries. Although any artery in the body can be visualized, the most common types of exams are CT angiograms of:

• Renal arteries (in hypertensive patients)

• Aorta

• Cerebral arteries (frequently looking for a cerebral aneurysm)

• Heart (evaluating coronary artery disease)

• Legs (in patients with symptoms relating to atherosclerotic narrowing in the arteries of the legs)

The exam is very brief, lasting no more than a routine CT scan (usually 20 seconds, with a total table time of about 30 minutes). It is non-invasive, and only requires an IV injection of contrast material. Therefore, the same restrictions apply to CT angiography as apply to any injection of iodinated contrast material (see above section on CT IV Contrast Material).

If you have any questions regarding CT Angiography, please contact one of our radiologists who would be happy to be of help.