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"How does a virtual colonoscopy CT scan detect tumors?"


I'm a 33 year old woman. I know colonoscopies can detect tumors, but can virtual colonoscopies also detec tumors?


Virtual colonoscopies have come into popularity in recent years because studies have suggested that they might be a reasonable alternative to traditional colonoscopies for the purposes of screening for colon cancer. Preparation for both the virtual and traditional colonoscopy is the same, which typically includes a combination of pill stool softeners and a large volume of liquid laxative on the day prior to the procedure. Patients undergoing the virtual colonoscopy will have a tube inserted into the rectum which will inflate it with air.

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A CT scan is then performed which focuses on the contours of the inside of the colon. The radiologist reading the scan should be able to identify abnormalities in the colon that could represent either cancer or polyps, which have the potential to transform into cancer. If any abnormalities are detected, then a traditional colonoscopy will need to be completed in order to better visualize the structure and obtain a tissue sample with biopsy. Some studies have suggested that virtual colonoscopies may not be as sensitive for picking up flatter lesions that could be dangerous. You should have a discussion with your physician about the pros/cons of each procedure prior to making a decision about which way to proceed.

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