Positron Emission Tomography (PET)

Positron Emission Tomography (PET) is a form of nuclear imaging which uses fluorodeoxyglucose (FDG) as the radiotracer. This allows a 3D image of metabolic activity to be generated using glucose uptake as a proxy marker. The images obtained are then combined with a conventional imaging technique such as CT to decide whether lesions are metabolically active.

Uses

• evaluating primary and possible metastatic disease
• assess response to treatment in certain cancers e.g. lymphoma post-chemotherapy
• assesses myocardial viability in ischaemic heart disease

Positron Emission Tomography using fluorodeoxyglucose (FDG) is considered a gold standard for assessing myocardial viability. Hibernating myocardium is characterised by reduced contractility and perfusion but preserved metabolic activity (glucose uptake). FDG-PET directly visualises this metabolic activity, making it highly effective at identifying viable tissue that is likely to recover function following revascularisation, thus predicting benefit from the procedure.