CT Virtual Colonoscopy

About  |  Patient Resources  |  Services

Each year, approximately 150,000 Americans are diagnosed with a very common and serious disease - colon cancer.


Colon cancer usually develops within benign growths called polyps, which arise from the colon wall. If polyps are detected early, removing them stops development of the cancer. The current standard technique for finding and removing polyps is endoscopy, a procedure in which a long, flexible tube is inserted into the colon, allowing a doctor to search for and remove polyps. Hartford Hospital offers virtual colonoscopy as an option when an incomplete colonoscopy has been performed or the patient cannot have a colonoscopy.

Virtual colonoscopy is much less invasive, requiring only a small rubber tip that is placed in the rectum to gently introduce air to inflate the colon. Most patients report that virtual colonoscopy is more comfortable than either barium enema or conventional colonoscopy. Hartford Hospital’s Department of Radiology has been offering 3-D Virtual Colonoscopy since 2002. Our highly-trained staff has extensive experience in performing 3-D virtual colonoscopy, ensuring the optimum in patient comfort and high quality results. Our radiologists have unsurpassed expertise in the interpretation of 3-D virtual colonoscopy.

A polyp can form at any time throughout life, but most commonly occurs in people over the age of 50. Most polyps grow slowly, and the risk that cancer will be found in a polyp is substantial only for polyps at least one half-inch (1 cm) in size. If your virtual colonoscopy shows no polyps, we will usually recommend that you wait five years before having another virtual colonoscopy or as recommended by your doctor.

Back to Top

Patient Resources

Patient Guide

CT Scan Patient Guide (English) Download
CT Scan Patient Guide (Español) Download

Before the Procedure

  • The night before your exam, proper bowel preparation is essential for a good exam. The colon needs to be prepared so that the radiologist can clearly see if any polyps are present. The special liquid that you drink passes through you and is not absorbed by your body. Because the liquid is not absorbed, it causes most people to have mild diarrhea on that evening only.
  • On the morning of the exam, you should strictly limit your diet to clear liquids, such as tea or apple juice.

What to Expect During a Virtual Colonoscopy

  • Virtual colonoscopy is designed to be easily tolerated by patients. The exam can be completed within twenty minutes, and most patients report that it causes little or no discomfort.
  • To begin, you will lie comfortably on the CT scanner table. A very small, flexible tube tip is inserted into the rectum and air is gently introduced into the colon. After the tube is inserted, your privacy will be maintained and you will be in control of the amount of air.
  • You may experience a sense of fullness, but nearly all patients report that the air insufflation is not painful.
    It takes about two minutes to perform the actual CT scan. The first series of pictures will be taken with you lying on your stomach, followed by another set lying on your back.
  • After the pictures are taken, the tube is removed and you will be free to go.
  • Because no sedation is required for the test, you can drive or return to work after the exam is completed.
  • Most people do not have polyps, but the smaller percentage of people who do should have them removed. If we detect a polyp on your virtual colonoscopy we will inform your doctor, and he or she will likely recommend a follow-up endoscopy to have the polyp removed.

Immediately following the exam, you may resume your regular diet.

Back to Top


  • Bone Densitometry

    Bone densitometry, also called dual-energy x-ray absorptiometry, DEXA or DXA, uses a very small dose of ionizing radiation to measure bone loss.

  • Coronary Calcium Score

    The coronary calcium score screening is a CT scan used to assess your risk of heart disease. In just five minutes, this non-contrast, non-invasive test allows doctors to take pictures of your heart and look for blockages in your arteries that can cause a heart attack.

  • CT Scans

    CT (computed tomography or CT scan) is an imaging technology that uses x-ray beams (radiation) and computers to create detailed, cross-sectional images of an area of the body.

  • CT Virtual Colonoscopy

    Each year, approximately 150,000 Americans are diagnosed with a very common and serious disease - colon cancer.

  • General Diagnostic Radiology

    General Diagnostic Radiology includes evaluation of the chest, spine, skull, extremities, hips, pelvis and abdomen. General diagnostic radiology is often used to evaluate suspected fracture or other indications of injury or abnormality.

  • Interventional Radiology

    The Department of Interventional Radiology and Neuroimaging’s staff physicians have all received specialized training and are all certified by the American Board of Radiology.

  • Mammography

    A mammogram is used to evaluate an abnormal clinical finding, such as a breast lump, that has been found by a woman or her physician.

  • MRI

    Magnetic resonance imaging (MRI) technology is unrivaled in its ability to produce high resolution images of soft tissue and structural anatomy.

  • Nuclear Medicine

    Nuclear medicine is a safe and painless imaging technology that uses small amounts of specially-formulated radioactive materials (tracers) to help diagnose and treat a variety of diseases.

  • PET Scan

    PET/CT combines the functional information from a positron emission tomography (PET) exam with the anatomical information from a computed tomography (CT) exam into one single exam.

  • Ultrasound

    In an ultrasound procedure, high-frequency sound waves (ultrasound) are transmitted to tissues or organs and make echoes.