(November 26, 2008 - Insidermedicine) While exploring the coronary arteries using computed tomography (CT) is almost as good as exploring them directly with a catheter, it is not accurate enough to replace the more invasive technique, according to research published in the New England Journal of Medicine.

Here is some information on CT angiography:

•    A CT scanner takes numerous X-rays and combines them to produce an image of the arteries.

•    Typically, the test involves being injected with a chemical that will help make the images sharper and lying on a table while the scanning equipment moves around you.

•    CT angiography is a quick and painless procedure.

In an international study, researchers from Johns Hopkins University assessed nearly 300 patients with mild-to-moderate calcium buildup in their coronary arteries using multidetector CT angiography, followed by conventional angiography, in which the arteries are explored directly with a camera-tipped catheter.

Overall, 56% of patients had obstructive coronary artery disease. Both methods were highly accurate at determining the presence and severity of this condition. The CT method, however, was slightly less able than angiography to definitively indicate the presence of the disease when it was there or to rule out the presence of the disease when it was not there.

We had a chance to speak with Dr. João Lima, the principal investigator of this study, who offered some further insight.

Today’s research indicates that using CT to study the coronary arteries is an accurate method of evaluating obstructive coronary artery disease, but it is not quite accurate enough to replace the more invasive angiography.

For Insidermedicine in Depth, I'm Dr. Susan Sharma.