Compared to regular x-rays, CT scanning uses a relatively low dose of radiation. Although non-invasive, the examination sometimes require a contrast material injected into a vein before scanning, in order to show fine details and highlight any abnormalities.
- Rapid procedure with an accurate evaluation.
- Non-invasive and painless.
- CT is less expensive, and more cost-effective, than MRI. In addition, it is less sensitive to patient movement. Unlike MRI, CT may be carried out in patients who have an implanted device of any kind.
- Exposure to radiation, with doses lower than those used in some general x-ray exams but higher than in others. Damaging effects of radiation may be more of a risk when multiple CT studies are carried out over a period of time.
- possible risk to the fetus: pregnant women should consult their physician first. Children should have a CT study only if it is essential for making a diagnosis. In general, the benefits of CT scanning outweigh the potential harm from radiation.
- Allergic reaction to iodine (contained in contrast material) such as itching, hives, nausea, or rapid breathing, which is easily treated. Severe reactions including difficulty breathing are quite rare but do occur. Kidney failure is another very rare occurrence; it is likeliest to develop in patients whose kidney function already is impaired.
- Nursing mothers should avoid breast-feeding their infants for 24 hours after receiving an injection of contrast medium.