Background Information

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Computed Tomography Colonography (CTC) also known as Virtual Colonography, is an emerging technique for the detection of polyps, which are small growths of tissue that can become cancerous, in the Colon.

Up to now, the Colonoscopy has been the best screening technique available.  While this technique is very accurate it is an invasive procedure which can cause both pain and embarrassment to the patient.

CTC examines the entire colon on a computer generated model.  It allows the radiologist to navigate through a virtual colon.

However, the radiologist still has to navigate through the entire colon and manually inspect the entire lining of the colon. This increases the overall examination time by comparison with conventional Colonoscopy.

The Vision Systems Group (VSG), School of Electronic Engineering at Dublin City University is researching an automated CTC.  The main objective of this is to remove the need for the radiologist to manually inspect the entire colon lumen, thereby allowing them to focus their efforts solely on the areas where there are polyps or other abnormalities.

The objective of the automated system is to flag these potential polyps and anomalies from the CTC data sets.  This increases the sensitivity of CTC as a colon cancer screening technique and decreases the time required to evaluate the screening results.

The problem associated with this approach is the number of 'false negatives' the automated system will produce.  'False negatives' are folds of tissue which are not polyps but which are detected as anomalies by the system. 

VSG is trying to maintain sensitivity while reducing the number of false negatives been flagged by the system.

See movie for a flythtu of the graphically rendered colon region. Can you find the polyps?

If the above movie is not supported by your computer system you may need to download the software at the following address: