Computed Tomography (CT) scan
What is it?
Computerised Tomography or CT scanning is a way of imaging the body using X-rays to produce a cross-sectional image. The patient lies on a couch which passes through a ring-shaped machine to generate the images of the organs being examined. Most scans are performed in under 2 minutes though the entire procedure can take up to 20 minutes.
Many studies examining the heart, abdomen or arteries require the use of intravenous contrast at the time of scan which will require the insertion of a cannula in the arm prior to the examination. If the examination is looking at the abdomen you may be asked to drink water prior to the study to outline the stomach and intestines.
The examinations can be performed at Frimley Park Hospital where there are two modern scanners which use the latest advancements in scanner technology to minimise the dose of radiation required to obtain the scan. CT scanners are also located at the Aldershot Centre for Health or Clare Park Hospital.
CT scans do involve exposure to x-ray radiation. However, this dose is small and the risk is therefore minimal. Nevertheless, this examination is not undertaken lightly and the radiologists and referring clinician would only perform this examination if it is felt that the benefit of an accurate diagnosis far outweighs any theoretical risk to the patient.
A useful dose calculator for a CT scan which also puts the small risks in perspective can be found at xrayrisk.com
CT Angiogram of the intracranial arteries
CT Angiogram of the cardiac arteries
CT virtual colonoscopy of the large bowel