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Virtual Colonoscopy


What you need to know about a virtual colonoscopy:

A virtual colonoscopy is a type of x-ray test to examine the inside of your colon (large intestine). Healthcare providers use a CT scan or MRI to take pictures of your colon from outside your body. This procedure may be used to check for polyps (growths) or cancer. The size of a polyp may also be monitored. You may need this procedure to check if colorectal cancer has come back after you had treatment. A virtual colonoscopy may be used if you are not able to have a regular colonoscopy.

What you need to do the week before your virtual colonoscopy:

  • Tell your healthcare provider if you know or think you are pregnant. CT scans are not used during pregnancy because of the risk to the unborn baby.
  • Contrast liquid is given to help polyps and other changes show up better in the x-ray pictures. Tell your healthcare provider if you have ever had an allergic reaction to contrast liquid.
  • Talk to your healthcare provider about all the medicines and supplements you take. You will need to stop taking medicines that contain aspirin or iron for 7 days before your colonoscopy. If you take a blood thinner, such as warfarin, ask when you should stop taking it.
  • Tell your healthcare provider if you have any metal in or on your body. If you are having an MRI colonoscopy do not enter the MRI room with anything metal. Metal can cause serious injury.

How to prepare for your virtual colonoscopy:

Your healthcare provider will have you prepare your bowels before your procedure. Your bowels will need to be empty before your procedure to allow him or her to see your colon clearly.

  • Drink clear liquids 1 to 2 days before your procedure. Clear liquids include plain gelatin, unsweetened fruit juices, clear soup, and broth. Do not drink any liquid that is blue, red, or purple.
  • Do not eat foods that are hard to digest. These include fruits, vegetables, cereal, nuts, peas, beans, popcorn, and tomatoes. Ask your healthcare provider for a list of foods to avoid. If you are having an MRI colonoscopy, you may also need to avoid any food that contains manganese (a metal), such as chocolate.
  • Follow your bowel prep as directed. Many different preparations can be given before a colonoscopy. With any bowel prep, stay close to the bathroom. This liquid will cause you to have bowel movements often.
  • An enema may be needed. Your healthcare provider may tell you to use an enema to help clean out your bowels.
  • Drink contrast liquid the night before your procedure. You will be given the liquid and instructions to follow. Drink the contrast liquid after you finish all of your bowel prep medicine.

What will happen during a virtual colonoscopy:

  • Your healthcare provider may give you medicine that will relax your colon. You will be asked to lie on your left side or on your stomach and raise one or both knees toward your chest. Your healthcare provider will examine your anus and use a gloved finger to check your rectum. Your healthcare provider will gently insert a thin, flexible tube into your rectum. If a CT colonoscopy will be done, air or carbon dioxide will be put into the tube. In an MRI colonoscopy, warm water or solutions with contrast liquid will be passed through the tube and into your colon. This expands your colon to help the doctor see it clearly.
  • During your procedure, the bed you are lying on will be moved inside the CT or MRI tube. Pictures will be taken as the bed or table moves and as you change positions. You may be asked to lie on your back or stomach. If the bowel is not expanded enough, more air or gas will be pumped into your rectum. You will have to hold your breath and stay still as each picture is taken.

What will happen after a virtual colonoscopy:

You may have some cramping or feel bloated after the procedure. You may need to lie on your left side with a heating pad on your abdomen. Eat small meals until the bloating improves.

Risks of a virtual colonoscopy:

A virtual colonoscopy may not find certain polyps or other problems in your intestines. Your healthcare provider will not be able to remove growths or take tissue samples to be tested. If contract liquid is used, it may cause you to have headaches, nausea, vomiting, flushing, or itchiness. You could also have an allergic reaction to the liquid. You may feel a little pain or discomfort as the small tube is placed inside your rectum. Your colon may get perforated (torn) due to increased pressure. If this happens, you will need to stay in the hospital and have surgery on your colon.

Seek care immediately if:

  • Your abdomen becomes tender and hard.
  • You have sudden trouble breathing.
  • You are dizzy or weak.
  • You have severe pain anywhere in your abdomen.
  • Your vomit has blood in it.
  • You develop a rash or hives.

Call your doctor if:

  • You feel full, bloated, or are not able to have a bowel movement.
  • Your bowel movements are black or have blood in them, or you are bleeding from your anus.
  • You have a fever within 24 hours of your procedure.
  • You have nausea or are vomiting.
  • You have problems having a bowel movement or urinating.
  • You have questions or concerns about your condition or care.

Relieve gas and discomfort from bloating

by lying on your left side with a heating pad on your abdomen. You may need to take short walks to help the gas move out. Eat small meals until the bloating improves.

Help prevent constipation:

  • Eat a variety of healthy foods. Healthy foods include fruit, vegetables, whole-grain breads, low-fat dairy products, beans, lean meat, and fish. Ask if you need to be on a special diet. Your healthcare provider may recommend that you eat high-fiber foods such as cooked beans. Fiber helps you have regular bowel movements.
  • Drink liquids as directed. Adults should drink between 9 and 13 eight-ounce cups of liquid every day. Ask what amount is best for you. For most people, good liquids to drink are water, juice, and milk.
  • Exercise as directed. Talk to your healthcare provider about the best exercise plan for you. Exercise can help prevent constipation, decrease your blood pressure and improve your health.

Follow up with your doctor as directed:

Write down your questions so you remember to ask them during your visits.

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The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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