A CT (computerised tomography) scan is a more sophisticated type of x-ray, which builds up a three-dimensional picture of the inside of the body. The scan is painless, but takes longer than a simple x-ray (10-30 minutes). It may be used to identify the exact site of the tumour, or two check for any spread of the cancer. Most people who have a CT scan are given a drink or injection ot allow particular areas to be seen more clearly. Before having the injection or drink, it is important to tell the person doing this test if you are allergic to iodine or have asthma.
A MRI (magnetic resonance imaging) scan is similar to a CT scan, but uses magnetic fields instead of x-rays. During the scan you will be asked to lie very still on a couch inside a metal cylinder. You will usually be given an injection to allow the pictures to be seen more clearly.
The test can take about 30 minutes and is completely painless, although the machine is quite noisy. You will be given earplugs or headphones. If you don’t like enclosed spaces you may find the machine claustrophobic. A two-way intercom enables you to talk with the people controlling the scanner.
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