Computed Tomography (CT) is an imaging modality which has become the primary tool for diagnosis of many medical conditions. Patients lie on a table which moves through a the circular CT scanner which emits x-rays to create images of the body and its internal structures.  CT scans are often able to identify abnormalities within the body only a few millimeters in size.

Sometimes this is done during or after the use of contrast, which is an iodine-based material given through an IV and helps to better show blood vessels, organs, and other internal structures. Your doctor will decide whether to use IV contrast, sometimes with the guidance of the radiologist. Occasionally, after a scan without contrast has been performed, it may be necessary to repeat the scan with contrast to better evaluate a possible abnormality. Some scans are also performed with oral contrast, which is contrast material that you drink before the scans to better show the digestive tract and associated structures.

CT scans are noninvasive or minimally invasive (requiring only an IV). Scans are very fast and painless, though some people feel a warmth inside the body during contrast administration.

CT Angiography (CTA) is a specialized form of CT with contrast in which the scan is performed during or shortly after contrast administration. CTA is utilized to specifically evaluate blood vessels, which may be in the brain, neck, chest, abdomen, or extremities. It allows radiologists to carefully evaluate the blood vessels for blockages or damage to the blood vessels such aneurysms, or dissection (abnormal tearing of the blood vessel wall). It is also used to evaluate for active bleeding which may be life threatening.