CT scanners take very good pictures of the inside of your body. These pictures help doctors to understand more about your health problem.
This page gives more information about CT scanning.
CT stands for computerised tomography. A CT scan uses x-rays to take detailed pictures of the inside of your body. It helps us find the cause of your problem and the best treatment options for you. A standard x-ray does not give the same level of detail as a CT scan.
CT scans use radiation, however the dose used is very small. The benefits of the scan are thought to outweigh any risks.
Sometimes we need to give you an injection of contrast dye before the scan, to help us see your internal organs better. This contains iodine, which some people are allergic to. Before your scan we will check whether you have had any previous allergies
The radiographer will ask you to lie on a motorised bed, which will move slowly through the scanning machine. Unlike some machines, the CT scanner is not enclosed.
You will need to lie very still while each picture is taken, to avoid blurring the images. You may also be asked to hold your breath for a moment.
You should not feel any pain during the scan. The most difficult part is keeping still. If you find it difficult or uncomfortable lying still, please tell the radiographer.
A scan usually takes 10 - 20 minutes, depending on the area of your body that is being scanned. If any preparation is needed, you may need to come to hospital 1 hour before your scan.
If you need an injection of contrast dye one of the CT staff will insert a small needle into a vein in the back of your hand. When it is injected, you might feel a hot flush and get a metallic taste in your mouth. Some patients can experience a sensation of passing urine but they don't actually do it. These sensations are normal and pass within minutes.
If we are scanning your abdomen, we may need to give you a drink which has contrast dye (or sometimes water). Try to avoid passing urine until your scan is over.
In most cases, you will be allowed to go straight home or back to the ward if you are an inpatient. You can eat, drink and go back to your normal activities straight away.
If you have had a contrast dye injection, you may need to wait 10 minutes before you can go.
The results will be sent to the doctor who referred you. If that doctor is a consultant at The Royal Liverpool and Broadgreen Hospitals, the results will normally arrive within 5 working days. If it was your GP or a consultant at another hospital, the results will normally arrive within 2 weeks.
If you are an inpatient, the results will be given to the doctors looking after you on the ward.