Before a virtual colonoscopy, you'll need to empty your colon. Any residue in your colon may obscure the images taken during the exam.
To empty your colon, follow your doctor's instructions carefully. You may be asked to:
June 09, 2014
- Follow a special diet the day before the exam. Typically, you won't be able to eat that day. Drinks may be limited to clear liquids. You may not be able to eat or drink anything after midnight the night before the exam.
- Take a laxative the night before the exam. You may also need to use a suppository to clear any remaining residue in your colon.
- Take medication to identify stool in your colon. The medication will help the doctor differentiate between colon abnormalities and stool residue.
- Adjust your usual medications. Remind your doctor of your medications at least a week before the exam. You may need to temporarily stop taking certain medications days or hours before the exam.
- AskMayoExpert. What is computed tomography (CT) colonography? Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2013.
- Kruskal JB, et al. Computed tomographic colonography. http://www.uptodate.com/home. Accessed Feb. 20, 2014.
- Yee J, et al. The time has arrived for national reimbursement of screening CT colonography. AJR. American Journal of Roentgenology. 2013;201:73.
- Pickhardt PJ, et al. Colorectal cancer: CT colonography and colonoscopy for detection — Systematic review and meta-analysis. Radiology. 2011;259:393.
- Sakamoto T, et al. Detection of flat colorectal polyps at CT screening colonography in comparison with conventional polypoid lesions. Acta Radiologica. 2012;53;714.
- Johnson CD, et al. The national CT colonography trial: Assessment of accuracy in participants 65 years of age and older. Radiology. 2012;263:421.
- Virtual colonoscopy. National Institute of Diabetes and Digestive and Kidney Diseases. http://digestive.niddk.6.gov/ddiseases/pubs/virtualcolonoscopy. Accessed Feb. 20, 2014.
- Pooler BD, et al. Screening CT colonography: Multicenter survey of patient experience, preference, and potential impact on adherence. AJR. American Journal of Roentgenology 2012;198:1361.