Alliance Medical > Professionals & Clinicians > PET/CT Scan

PET stands for Positron Emission Tomography. It's an imaging technique that uses small quantities of a radioactive tracer called 18F-Fluorodeoxyglucose (similar to sugar), to produce images showing the chemical and physiological changes within the patient
CT (Computed Tomography) utilises X-rays to produce pictures showing the density of different organs in the body
By combining these two techniques in one scanner, we're able to produce images that illustrate active pathology and anatomical location in astonishing clarity
This technique is primarily used in the diagnosis and management of patients in oncology, however, it also has applications in cardiology and neurology
Unlike some other diagnostic procedures, PET/CT scanning typically needs important patient preparation, for example, a six hour fast prior to the procedure and, in some instances, bowel preparation
Click here to watch a quick overview video, aimed at patients
And click here to listen to PET/CT patient, Mark, tell his story

There is a small amount of radiation involved in the procedure, similar to other diagnostic scan procedures such as CT
The risk associated with this is very small and it's considered that the risk of missing a serious problem if you don't have a PET/CT scan is much higher
This imaging technique has been used safely since 1973, with many thousands of examinations being performed on patients around the world each day
The radioactive component of the PET/CT scan is called Fluorine–18. Fluorine is attached to glucose in the injection given to the patient
Radioactivity is often described in terms of its half-life. Half-life is defined as the time taken for radioactivity to fall to half its initial level
Fluorine has a half life of 110 minutes. This means that the level of radioactivity remaining in the body halves every 110 minutes
Therefore, it's safe to say that within 8 hours there will be an insignificant amount of radioactivity in the body
Patients who are pregnant will not receive a PET/CT scan so in this instance, a further consultation with the clinician should be arranged

Our patient area has comprehensive and easy to understand information on the procedure - you can access this here

We've put together a useful collection of straightforward, single-page diagrams illustrating typical diagnostic care pathways - please click to view and download:

Click to view

Referring your patient is an easy, two-step process:
- Step 1: select your preferred imaging centre
- Step 2: complete and return the relevant referral form
And, if you have any questions, just contact our dedicated Patient Management Centre on 0845 045 0600, we'd be glad to help