Computerized tomographic angiography, also called CT angiography or CTA, is a test that combines the technology of a conventional CT scan with that of traditional angiography to create detailed images of the blood vessels in the body.
In a CT scan, x rays and computers create images that show cross-sections, or slices, of your body. Angiography involves the injection of contrast dye into a large blood vessel, usually in your leg, to help visualize the blood vessels and the blood flow within them. When the contrast dye is used to visualize your veins, the study is called a venogram, and when it is used to visualize your arteries, it is known as an arteriogram.
CT angiography is similar to a CT scan, but the contrast dye is injected into one of your veins shortly before the x ray image is performed. Because the dye is injected into a vein rather than into an artery, as in traditional angiography, CT angiography could be considered less invasive.
Your physician may order CT angiography to help diagnose a narrowing or obstruction of the arteries, an aneurysm, deep vein thrombosis, pulmonary embolism, or another vascular condition.
CT exams are generally painless, fast and easy. With multidetector CT, the amount of time that the patient needs to lie still is reduced.
Though the scanning itself causes no pain, there may be some discomfort from having to remain still for several minutes and with placement of an IV. If you have a hard time staying still, are very nervous or anxious or have chronic pain, you may find a CT exam to be stressful. The technologist or nurse, under the direction of a physician, may offer you some medication to help you tolerate the CT scanning procedure.
For exams (excluding head and neck) your head will remain outside the hole in the center of the scanner. The scanner is approximately 24 inches wide, therefore, your entire body will be “inside” the scanner at one time such as with MRI.
Angiography may eliminate the need for surgery. If surgery remains necessary, it can be performed more accurately. CT angiography is able to detect narrowing or obstruction of blood vessels allowing for potentially corrective therapy to be done. CT angiography may give more precise anatomical detail than magnetic resonance imaging (MRI), particularly in small blood vessels.