Q. Is this test as accurate as colonoscopy?
A. A recent large study (SIGGAR study of over 5000 patients in the UK published in the Lancet 2013) has been performed, comparing this test to colonoscopy and barium enema. CTC was shown to be as accurate as colonoscopy for detection of cancer and large bowel polyps (the precursor of cancer) and superior to the existing radiological test, barium enema.
Q. Is this test similar to a barium enema?
A. No, this test is different, using a CT scanner, no liquid enema and requiring less patient movement. CTC is better tolerated than barium enema and more accurate.
Q. Is this test just for my bowel or will it show anything else?
A. CTC will provide information about organs outside the bowel within your abdomen and pelvis including detection of aortic aneurysm and review of liver, pancreas, spleen, pelvic organs and kidneys.
Q. I have already had a colonoscopy which was difficult; how is this test different?
A. During this test a small flexible tube (diameter of a pencil) is inserted into the rectum through which gas is passed. The gas will gradually fill the loops of bowel which is achieved more easily than trying to pass the scope around the bowel.
Q. Last time I had a test that involved laxatives I found it very difficult to manage, is there an alternative to standard 'full' laxatives?
A. Yes. The bowel can be prepared by using a liquid which mixes with the bowel contents so that they can be seen on the scan (and rapidly discriminated from polyps or cancer). This liquid may give you diarrhoea, but on average is easier to manage than taking standard bowel preparation (strong laxatives).
Q. I am diabetic, can I still take the bowel preparation?
A. Yes. 1. If your diabetes is controlled only by tablets or by diet and you are able to measure your own blood sugar then most people can continue with the diet as instructed. Taking laxatives can reduce your blood sugar so you may have to monitor your blood sugar level more frequently than usual. If you have difficulty managing to maintain a balanced sugar level, please see below. 2. If your diabetes in controlled by insulin or if you have difficulty in maintaining a balanced sugar level we can adjust your preparation accordingly – please phone us. Q. Why do I need to be on a restricted diet for one or two days before this test? A. Some foods make it more difficult to clean the bowel. The diet recommended for CTC is designed to help with the bowel preparation.