How to Prepare for your CT Colonography
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CT colonography (CTC) is a minimally invasive CT exam that produces a 3D view of the colon. During the exam, a small tube is placed in the rectum and air is passed though the tube into your bowels. You must be able to hold your breath for 30 seconds and lie on your back and stomach or side. You may experience mild discomfort but should not feel any pain. Depending on the reason for the study, you may receive an intravenous injection of iodinated contrast material. You will be in the CT room for approximately 30 minutes.
This guide will help you prepare for your CT colonography by properly cleaning out your colon. To ensure the highest quality study, it is very important that you strictly follow these directions.
If you have a history of severe constipation or have had difficulty with bowel preparations previously, please speak with your physician before beginning this preparation.
The prep consists of 3 parts:
- A low fiber diet, beginning 3 days before your exam.
- A clear liquid diet, beginning 1 day before your exam.
- A prep kit containing MiraLAX, Tagitol suspension, and Gastrografin oral contrast agent.
If you have diabetes and take medication, contact your physician to determine if changes should be made in your medication regimen (insulin or pills).
If you have a history of severe constipation or have had difficulty with bowel preparations previously, please speak with your physician before beginning this preparation.
Prep Day 1: Three (3) Days Before your Exam
Follow the suggested low fiber menu below 3 days before your exam, starting with lunch. Review the items you can eat and drink and the items to avoid on the next page before choosing your meals.
12:00 Noon (Lunchtime)
- Soup
- Fish or white meat chicken
- White bread / crackers
- White rice
- Fruit or dessert
6:00 PM (Dinner)
- Soup
- Fish or white meat chicken
- White bread / crackers
- White rice, pasta, or potato (no skin)
- Fruit or dessert
You CAN eat
- Up to 2 cups of low-fat dairy products including milk and plain yogurt
- Plainly prepared fish, poultry, eggs
- White rice
- Spaghetti, noodles, macaroni
- Potatoes (no skin)
- White bread
- Bouillon or broth
- Soups, strained or made with allowed vegetables and/or meat
- Refined beans
- Saltine crackers
- Canned fruit (no seeds, skin, or membranes)
- Gelatin
- Jelly
- Popsicles or fruit ice
- Salt and pepper
- Sugar
- Honey
- Syrup
Please AVOID (Do NOT eat or drink):
- Any beverages not listed above
- Yogurt with fruit skins or seeds
- Strongly flavored cheeses
- Added fats, gravies, fried sauces
- Peanut butter
- Brown rice
- Whole grain breads and cereals
- Popcorn
- Raw fruits
- Raisins or dried fruits
- Prunes / Prune juice
- Coconut
- Nuts and seeds
- Hard candies
- Strong flavored spices including cloves, garlic, and seed spices
- Strong flavored sauces including chili sauce, barbeque sauce, and mustards
- Jam / Marmalade
Prep Day 2: Two (2) Days Before your Exam
Continue the low fiber diet, eating and drinking only those foods you can eat as outlined on the previous page of this guide.
Prep Day 3: One (1) Day Before your Exam
Take your regular medications unless otherwise instructed by your physician.
Begin a clear liquid diet. Please DO NOT consume any solid food or any milk or dairy products.
You may eat or drink any of the following clear liquids:
- Clear soup (any broth without solid materials)
- Strained fruit juices without any pulp
- Flavored or unflavored gelatins (do not add any extra ingredients)
- Black coffee or plain tea (no milk, cream, or creamers)
- Soft drinks
Prepare your MiraLAX mixture by mixing all 238 grams of the MiraLAX powder with 64 ounces of room temperature clear liquid until the powder dissolves. Once it is dissolved, you may chill the mixture – many people find the mixture tastes better when it’s chilled! DO NOT mix the MiraLAX earlier than the morning of the day before your procedure.
8:00 AM
- Have a clear liquid breakfast.
- Take 2 (5 milligram) bisacodyl tablets – DO NOT crush or chew them and DO NOT take them within an hour of antacids (such as Tums).
- Drink 1 bottle (20 mL) of Tagitol.
12:00 Noon (Lunchtime)
- Eat a clear liquid lunch and drink at least 8 fluid ounces of clear liquids.
- Drink 1 bottle (20 mL) of Tagitol.
1:00 PM
- Drink half of the MiraLAX mixture.
2:00 PM & 3:00 PM
- Drink at least 8 fluid ounces of clear liquids.
4:00 PM
- Drink the other half of the MiraLAX mixture.
5:00 PM
- Drink at least 8 fluid ounces of clear liquids.
6:00 PM
- Drink at least 8 fluid ounces of clear liquids.
- Drink 1 bottle (20 mL) of Tagitol.
7:00 PM
- Drink at least 8 fluid ounces of clear liquids.
10:00 PM
- Add one 30ml bottle of Gastrografin to 8 ounces of cold water (or other clear liquid). Stir gently and drink.
During the remainder of the evening, you may drink clear liquids if desired, but DO NOT eat solid food until after the procedure is completed the following day.
Prep Day 4: The Morning of Your Exam
Take your regular medications with water unless otherwise instructed by your physician.
If you have an afternoon procedure, you may have clear liquids until 10 AM.
Contact Information
For questions about your exam, please call the office directly.
- CMC Main, CT Department (704) 355-2267 or (704) 355-2268
- Carolinas Imaging Services:
- Ballantyne (704) 697-5000
- Rock Hill (803) 992-7220
- South Park (704) 333-3794
- Matthews (704) 844-9040
- Denver (704) 464-5704
- Huntersville (704) 895-3445
- Morehead Imaging Center (704) 446-5230
