The FDG-PET / CT Scan, Normal Uptake, Artefacts, and Pitfalls - A Pictorial Essay

Dr. Vijaya Kumary Baskara Pandian, Dr. Bharath Veerabadhran Murugan, Dr. Venugopal G.

Abstract: A cancer radiologist needs to be well-versed in the normal patterns of uptake, artefacts, and pitfalls of Positron Emission Tomography - Computed Tomography (PET-CT) scan to lessen the incidence of false-positive findings. A normal PET scan will demonstrate fluorodeoxyglucose (18F- FDG) uptake in the brain, kidneys, bladder, and heart. In this pictorial essay, we will be highlighting the areas of normal FDG uptake, non-oncologic causes of FDG uptake ? including inflammatory and non-inflammatory causes - that can mimic pathological uptake. These examples are drawn from experience at a tertiary cancer care centre. This can help us to potentially avoid misinterpretation of uptake, unnecessary follow-up imaging, and invasive tests. This pictorial essay is based on retrospective and anonymised imaging data obtained from PET-CT images of the tertiary cancer care centre. No identifiable patient information is included. Ethical approval was not required in accordance with institutional guidelines, since it is an educational, image-based study with no patient data.

Keywords: Artefacts, FDG (Fluorodeoxyglucose), PET/ CT (Positron Emission Tomography/ Computed Tomography), Uptake, Benign, Malignant