Virtual (Digital) Colonoscopy
Digital colonoscopy, a.k.a. a CT colonography is a method of receiving images using a computed tomography as in optical colonoscopy.
Preparation: cleaning the colon – by taking a medication (orally, and under a prescribed schedule of intake) as well as a diet excluding intake of food rich in cellulose.
During the examination a slim catheter is inserted in the anus and the colon is filled with gas – air or carbon dioxide. A CT scan is carried out and the information is being processed by the computer to show a digital image of the colon.
When carried out successfully, digital colonoscopy can find tumors or polyps even when they are “hidden” in the folds of the intestines and usually undetected by the classic colonoscopy. The examination lasts some 10 minutes, it isn’t painful and it doesn’t require anesthesia.
A disadvantage here is that the found polyps can’t be removed during the procedure because the removal requires an optical colonoscopy. Besides, as a method using radio beams, there is a considerate decrease in the level of irradiation but it yet remains a type of X-Ray examination.
Sometimes a contrast agent is needed in order to obtain a more detailed image of a certain change or modification in other organs in the abdomen.
How is it useful?
̶ Timely discovery of polyps of the colon and their removal is the surest way of prevention of colon cancer
̶ Monitoring of detected but unremoved polyps
̶ Monitoring of post-surgery patients who have intestinal cancer – in case of doubts of disease relapse
̶ Patients complaining of problems with the colon and who do not want to undergo a conventional optical colonoscopy or who aren’t in a condition to undergo such a procedure (elderly or patients after a heart surgery, etc.)
̶ When the colonoscopy can’t examine the entire colon due to stenosis caused by a tumor, adhesions or another reason.
The method is not applied neither in assessing treatment of colitis or diarrhea nor in treating colon bleeding.
