A CT scan, also known as ‘tomodensitometry’, is an examination which uses a computerised x-ray imaging procedure. A narrow beam of x-rays is aimed at a patient and quickly rotated around the body, producing signals that are processed by the machine’s computer to generate cross-sectional images (or “slices”) of the body. Pictures need to be interpretated by a specialist to obtain a diagnosis. Frequently an iodine product is used to enhance the quality of the images; which is injected by perfusion (using a drip).