What are CT colongraphy’s strengths and limitations?

CTC provides a time efficient procedure with minimal invasiveness. No sedation or recovery time is required, nor is a chaperone needed to provide transportation after the procedure. Time permitting, patients can return to work on the same day.

Several limitations of CTC exist. Since it is an “image-only” test, patients with polyps of significant size will require colonoscopy to remove the polyps. CTC also requires the same full bowel preparation and restricted diet as optical colonoscopy, which may decrease patient adherence. While same-day polyp removal can be offered without the need for additional preparation, this requires coordination between medical specialists (radiologists and endoscopists) and facilities (radiology departments and endoscopy suites). Reimbursement for CTC is limited, although 47 states now offer Medicare reimbursement for diagnostic CTC for certain clinical indications (typically limited to patients who have had an incomplete optical colonoscopy).

Potential harms from CTC are related to the procedural risks associated with bowel preparation, colonic distention, and radiation exposure due to CT scanning. The risks associated with bowel preparation are similar to those for optical colonoscopy. Because CTC is a minimally invasive test, the risk for colonic perforation due to distention is low. In addition to views of the colon, CTC also captures images of the abdomen and pelvis. Abnormalities outside the colon are commonly identified, and a significant proportion of these abnormalities require additional evaluation, with associated costs and risks to patients.