What is CT Colonography?

CT Colonography, or Virtual Colonoscopy, is a CT scan procedure used to visualise the large bowel (colon) using 2-dimensional and/or 3-dimensional images.

CT colonography is performed on an empty bowel and sedation is generally not required. The colon is distended by insufflation with carbon dioxide or air, via a small rectal tube. Distension is vital for effective polyp detection when performing CT Colonography.

In recent years the radiology community has embraced the potential offered by the fast developing world of CT colonography since it offers an accurate, rapid and minimally invasive means of imaging the large bowel. The CT colonography option is also embraced by patients. In a survey of over 2,000 patients who had received both CT colonography and optical colonoscopy, 46% expressed a preference for CT colonography vs 24.9% who preferred optical colonoscopy¹. In addition CT colonography has been shown to be cost effective and to improve colorectal cancer prevention rates².

1. B. Siewert et al. Patient acceptance and preference of CT colonography compared to optical colonoscopy for colon cancer screening. Poster presented at the American Society of Clinical Oncology May 31st 2009. J Clin Oncol 27:15s, 2009 (suppl; abstr 4034).
2. Regge D et al. Impact of computer-aided detection on the cost-effectiveness of CT colonography. Radiology. 2009 Feb; 250(2): 488-97.