CT scanning does involve x-rays, and so has the usual risks associated with ionising radiation.

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1 Information for Patients having a CT Virtual Colonoscopy Scan. The Radiology Department The Radiology Department, sometimes called the X-ray or Imaging Department, is the facility in the hospital that carries out radiological examination of patients. The Department uses a range of x-ray equipment, together with computed tomography (CT scan), ultrasound and magnetic resonance imaging (MRI). The Radiologists are doctors specially trained to interpret the images and carry out some of the more complex examinations. Radiographers, who are highly trained to carry out many of the x-ray and other imaging procedures, support them. What is a CT virtual colonoscopy scan? A CT (Computed Tomography) scanner is a special x-ray machine that produces an image of a cross-section, (or slice) of the body. The scanner consists of a doughnut shaped structure, or gantry, about two feet thick. You pass through this machine on a couch. A narrow fan-shaped beam of x-rays is produced from inside the gantry, and rotates in a complete circle around you. The x-rays pass through the body and are detected by electronic sensors on the other side of the gantry. The information passes to a computer, which then produces a picture of the internal structure of the body. The pictures are displayed on a TV screen, and can be examined by a Radiologist. A virtual colonoscopy is a test that involves using a CT scanner to produced two and three dimensional images of the whole of the large bowel (colon and rectum). During a virtual colonoscopy gas is used to inflate the bowel via a thin flexible rubber tube placed in your back passage. CT scans of your abdomen and pelvis are then performed with your first lying on your front and then on your back. In addition the scan will also look at other organs of your abdomen. Are there any risks? CT virtual colonoscopy is generally regarded as a very safe test. Problems can occur rarely, and if they do, they are similar to those which could happen with other methods of examining the large bowel. These include:- - Abdominal discomfort - Faint like reactions - Reaction to the injected contrast - There is a very small risk (less than 1 in 3000) of causing a hole in the bowel. However, this risk is lower than other invasive ways of looking at your bowel. CT scanning does involve x-rays, and so has the usual risks associated with ionising radiation. IMPORTANT For female patients between the ages of years this examination must be performed within the first 10 days after the start of a menstrual period. Please inform the department if your examination date falls after this time.

2 The amount of radiation is more than is used for an ordinary x-ray of the chest or body, and is equal to the natural radiation we all receive from the atmosphere over a period of approximately three years. This adds very slightly to the risk of for example, developing a cancer. However, as one in three of us will develop a cancer at some stage during our lives, the added risk is very small and also the risks from missing a serious disorder by not having a CT scan are considerable. The doctors in the Radiology Department are trained to deal with any complications and again the risk involved is very small. If you have had a reaction to a previous injection of contrast material given for a kidney x-ray (IVU.IVP) or a previous CT scan you should tell the Radiographer at the time of your examination. Despite these slight risks, your doctor believes it is advisable that you should have this examination and do bear in mid there are greater risks from missing a serious disorder by not having it. What preparation will I need? Laxatives In preparation for your CT virtual colonoscopy, it is important that your bowel is prepared and free from faeces, so it is extremely important that you follow the diet plan we give you. You will be given very strong laxatives which will make you empty your bowels. You will also need to stop eating for a period of time before your test. If you are an insulin dependent diabetic, could you please inform us before following the instructions below. The direct phone number is Preparation instructions The laxative we will give you is called Picolax. Each sachet needs to be dissolved in a cup of cold tap water (about 150mls). Please be prepared for frequent bowel movements within three hours of taking the first dose. 1. You should follow a low fibre residue diet (information below) for 4 days prior to the day of examination. 2. DO NOT TAKE iron tablets, bran or Osogel for 4 days prior to the day of the examination. 3. DO NOT EAT ANYTHING from 10pm 2 days before the examination. 4. You must continue to DRINK PLENTY OF FLUIDS which may include water, energy drinks, black tea or collect, fizzy drinks, squashes, clear soup or herbal teas. It is important you drink as much as possible during this time. You may also suck boiled sweets.

3 5. At 8am on the morning OF THE DAY BEFORE the examination, open one of sachets and mix the powder with three or four dessert spoons of water. Wait a few minutes then fill the glass with cold water. Drink the contents. 6. At 2pm on the afternoon OF THE DAY BEFORE the examination, repeat as above with the second sachet of Picolax. If you have any queries please call the CT coordinator on LOW RESIDUE DIET PLEASE START A LOW RESIDUE 4 DAYS BEFORE THE DAY OF THE EXAMINATION. ALLOWED Dairy Meat Potato Bread Limit to 2 cups per day use low fat products, semi or skimmed milk Plain yogurt Plainly prepared fish, poultry Eggs boiled or poached Boiled white rice, spaghetti, noodles, macaroni, potato with no skin Cereal, rice crispies or plain cornflakes white breads Chappattis made with white flour plain naan bread Fruit/ juices Clear fruit juice Beverages Soup Desserts Misc Coffee (limited), fruit flavoured drinks, tea, carbonated drinks, herbal / fruit drinks, energy drinks Broth, strained soups Clear jelly, fruit ice, popsicle Salt, pepper, jelly, sugar, honey

4 PLEASE AVOID Dairy Meat Potato Bread Yogurt with fruit or seeds Strongly favoured cheese Added fats, gravies, fried sauces Heavy seasoning, peanut butter Potato with skin, brown rice, No other fruit or vegetables or fruit No lentils, chick peas No fresh or tinned tomatoes Whole grain breads Corn, other cereals or popcorn No popodoms No gram flour Fruit / juices Raw fruit, raisins, dried fruit Prunes, skins, no tinned fruits Beverages Soup Desserts Misc All others All others Coconut Nuts Seeds, Hard sweets cloves, garlic, seed spices, chilli sauce, barbecue sauce, jam Can I bring a relative / friend? Yes, but for safety reasons, they cannot accompany you into the CT scanning room except in very special circumstances. When you arrive Once you have checked in, you will be shown to where you will be collected by the Radiographer, or other member of staff. You will be asked to drink a jug of flavoured water for 2 hours to show the inside of your bowel. Toilets are clearly sign posted, should you need to use then. When you go for your x-ray The Radiographer will explain the procedure for your examination, and show you to a private cubicle to undress and remove any watches and jewellery. You will be asked to put on the surgical gown and dressing gown provided, but you may prefer

5 to bring your own dressing down. You will be asked to place your clothes and any personal items either in a locker or a basket that you keep with you. Who will see you? A small team including a Radiologist and a Radiographer will care for you. The Radiographer will carry out the scan. It is the Radiologist who will look later at the recordings of the images before writing a report on his / her findings. What happens during the scan? - The Radiographer will explain the test and answer any questions. Please let him / her know if you have had any problems with your bowel preparation. - You may have a cannula (drip needle) inserted into one of the veins in your arm. - You will be asked to lie down on the scanner table on your left side. - The Radiographer will pass a short thin flexible tube into your back passage. - A muscle relaxant may be injected to avoid bowel spasm. - Gas (carbon dioxide) will be gently introduced into your bowel through the tube in your back passage. This is better and more comfortable than injecting room air. - This is done at a controlled rate by a machine specifically designed for this purpose. - Once the Radiographer is satisfied with the amount of gas in your large bowel, a CT scan will be taken with you lying on your front. - You will then be asked to turn onto your back for a second scan. - For the second scan you may be given a contrast injection via the cannula. This may make you feel warm or give a metallic taste in your mouth. - During the scan you may be asked to hold your breath for about seconds. How long will it take? The procedure will take about 20 minutes but please allow an hour for the appointment. Although we make every effort to adhere to our appointment times, delays may occur due to emergency patients from either the accident unit or the wards. Are there any side effects? You be able to go home straight after the test although we recommend that you stay with us after your scan for 15 minutes when we will offer you a drink of tea or coffee and a biscuit. Can I eat and drink afterwards? Yes, do so normally. You are advised to drink plenty of fluids afterwards. When will I get the results? The Radiologist will examine your CT scan shortly after your visit and prepare a report on the findings for your Consultant. Your doctor will then discuss the results with your at the follow up appointment in outpatients.

6 Additional sources of information This leaflet is based on one designed by the Clinical Radiology Patients liaison Group of the Royal College of Radiologists, but has been modified (with permission) by us to reflect local policies. The Royal College of Radiologists web site (http;// has further information on radiology. For further information on Heart of England Radiology Department visit