Colon imaging in radiology departments in 2008: goodbye to the routine double contrast barium enema.

We radiologists are free to choose DCBE or CTC when patients are referred to us for colonic examination. The studies reported during 2007 have confirmed that CTC is more accurate, preferred by patients, with a shorter room time, fewer complications, lower radiation exposure, and reveals therapeutically significant extracolonic lesions in 5% to 10% of cases, so that it is beginning to seem rather irresponsible to continue to offer routine DCBE examinations. In older patients the yield of extracolonic abnormalities is even greater, with 505 abnormalities found in 268 of 400 consecutive patients aged 70 years and older, including 23 extracolonic malignancies. More than 90 Canadian radiology departments have bought the necessary carbon dioxide insufflators, so there is clearly great interest. Many training workshops are available in Europe and the United States to help radiologists become familiar and skilled with CTC, and it will be helpful to have more local ones within Canada over the next few years. Some studies have shown that CTC can be done with poorer results than those I have quoted, and this is often in the early experience of departments. As large numbers of radiologists train, there is the potential for hundreds of errors while experience is being gained. We have the advantage over endoscopists, in that we can train on known data sets. Several institutions have put together sets of 50 complete CTC cases, mixed abnormal and normal, and these are an ideal training tool so that one can make one's mistakes in training rather than on live patients. One such data set is even available with one of the recent textbooks. Would it be useful for the CAR, or provincial radiology associations, to purchase several of these sets, and make them available for an appropriate fee to radiologists who are learning? CTC technologists will necessarily have a role on the workstations, including doing the primary read. Additional budgets will be needed for CTC with a diminution in fluoroscopy budgets as barium enemas are discontinued. Some larger hospitals may reserve a scanner purely for alimentary tract work- perhaps CTC and CT enterography. The essential administrative breakthrough will be to establish either a technical fee for CTC or an appropriate increase in the hospital global budget to allow high-volume CTC to flourish Nationally standards and guidelines will be needed, and if we are to play a major role in screening, where high standards have to be evaluated and maintained, we may need nationally organized individual audit feedback, much as we have with breast screening. Should the known data sets have a role in training for radiologists embarking on screening or in demonstrating continued competence? It is an exciting time once again for radiologists interested in colonic disease. We now know that CTC can be done very well. The challenges are going to be achieving consistency and deciding which of the 6 areas of opportunity described above are our priorities.