Diagnostic utility of positron emission tomography-computed tomography and indications for 18F-Fluorodeoxyglucose and amyloid-tracers

Positron emission tomography-computed tomography (PET-CT) is a nuclear medicine imaging technique widely used in oncology, cardiology and neurology where it’is becoming of great interest especially because of its role in the diagnosis and differential diagnosis between several pathological conditions involving the nervous system. In neurodegenerative diseases, the most used PET-CT radiopharmaceuticals are ¹⁸Fluoro-Fluorodeoxyglucose (¹⁸FFDG), a glucose analogue that is able to identify abnormalities of cerebral glucose metabolism, and amyloid-tracers (11C-PiB, ¹⁸F-Florbetapir, ¹⁸F-Flutemetamol, ¹⁸F-Florbetaben) that are able to detect presence of amyloid plaques. Depending on the specific characteristic of tracers and patient’s disease, the examination has dedicated appropriate indications that are illustrated in this article. PET-CT, with its several tracers, is an accurate tool in evaluating neurodegenerative diseases. ¹⁸F-FDG is considered a hallmark of the stage of the disease. Glucose hypometabolism in specific cerebral areas allows distinguishing different degenerative diseases. Amyloid tracers are considered the hallmark of the state of the disease. The uptake of PET-amyloids tracers reflects the cortical regional density of amyloid plaques.