Edinburgh Imaging

What is a PET-CT scan?

A PET-CT scanner is a PET scanner combined with a CT scanner.

What is a PET scan & what is it used for?

A Positron Emission Tomography (PET) scanner produces detailed, three-dimensional images of how the cells are working inside the body.

PET scans can be used to help diagnose a range of different cancers & can show how far a cancer has spread or how well it is responding to treatment.

They can also be used to help diagnose a number of conditions that affect the normal workings of the brain (neurological conditions), such as dementia.


What is a CT scan & what is it used for?

A computerised tomography (CT) scaner uses X-rays & a computer to create detailed images of the inside of the body, including the internal organs, blood vessels & bones.


What is a PET-CT scan & what is it used for?

The scanner itself is a CT scanner joined together with a PET scanner, which together form quite a long tunnel in which the paient lies. The tunnel is quite wider & the table moves slowly through as the patient has his or her scan done.

The CT scanner component allows reconstruction & registration of the detailed PET images. This allows the PET information about cellular function, to be located quite precisely with its anatomical location, as determined by the CT scan.

Complex CT scans, such as coronary artery angiograms, can be combined with PET scans, so that the 2 types of image can be viewed overlaid over each other. This helps to localise where an area of disease may be, such as a tumour or a narrowing of the heart blood vessels.