Benefits and Risks – CT Colonography

Benefits

• This new minimally invasive test provides both 2-D and 3-D images that can depict many polyps and other lesions as clearly as when they are directly seen by conventional colonoscopy.
• CT colonography has a markedly lower risk of perforating the colon than conventional colonoscopy. Most people who undergo CT colonography do not have polyps, and can be spared having to undergo a full colonoscopy.
• CT colonography is an excellent alternative for patients who have clinical factors that increase the risk of complications from colonoscopy, such as treatment with a blood thinner or a severe breathing problem.
• Elderly patients, especially those who are frail or ill, will tolerate CT colonography better than conventional colonoscopy.
• CT colonography can be helpful when colonoscopy cannot be completed because the bowel is narrowed or obstructed for any reason, such as by a large tumor.
• If conventional colonoscopy cannot reach the full length of the colon—which occurs up to 10 percent of the time—CT colonography can be performed on the same day because the colon has already been cleansed.
• CT colonography provides clearer and more detailed images than a conventional barium enema x-ray examination.
• CT colonography can detect abnormalities outside of the colon, including early-stage malignancies and potentially dangerous conditions, such as abdominal aortic aneurysms.
• CT colonography is tolerated well. Sedation and pain relievers are not needed, so there is no recovery period.
• CT colonography is less costly than colonoscopy.
• No radiation remains in a patient's body after a CT examination.
• X-rays used in standard CT scans have no immediate side effects.

Risks

• There is a very small risk that inflating the colon with air could injure or perforate the bowel. This has been estimated to happen in fewer than one in 10,000 patients.
• There is always a slight chance of cancer from excessive exposure to radiation. However, the benefit of an accurate diagnosis will generally outweigh the risk.
• The effective radiation dose for this procedure varies.
• Women should always inform their physician and x-ray or CT SMIL Technologist if there is any possibility that they are pregnant.
• CT scanning is, in general, not recommended for pregnant women unless medically necessary because of potential risk to the baby.