Description

It works in an entirely different way to other imaging techniques such as X-rays, CT scanning or MRI scanning.

PET scans display chemical and physiological activity in various parts of the body and therefore, provides information about how an organ is functioning. This is different to other scanning methods which look at structure and anatomy of organs.

However, the main area for PET scan use is for cancer studies, where scanning is used for diagnosing cancer and assessing its spread. It can be used to distinguish between benign and malignant disease, establishing the extent of spread, measuring response to therapy and locating primary (the original tumour) and secondary (tumours that have spread from the original) sites.

In heart disease, PET scanning is used for assessing blood flow rates at rest and during exercise, for checking the state and health of heart muscle before possible surgery and is very revealing in the assessment of coronary artery disease.

For neurological problems in the brain, PET scans are used in assessing epilepsy, dementia and Parkinsons patients as well as those with other conditions.

The process works by injecting a radio-marker into the blood stream which is taken up by tissues in the body with a high metabolic rate such as cancer cells. This marker can then be tracked by a computer to display the site, extent and functioning of those.