Hybrid imaging of aortitis through 18F-FDG PET/CT and computed tomography angiography: a pictorial review

Aortitis is a clinical condition characterized by inflammation of the aortic wall, which can lead to severe complications if untreated. The condition includes various diseases affecting the aorta and its branches, with several etiologies such as septic, non-septic, and those related to endovascular prostheses. Accurate diagnosis is crucial, yet challenging, due to variations in clinical presentation and diagnostic criteria. Recent advances in imaging modalities, such as Computed Tomography Angiography (CTA) and 18F-FDG PET/CT, have improved the ability to detect and manage aortitis. This study includes clinical cases focusing on septic and aseptic aortitis and prosthetic graft infections. The use of 18F-FDG PET/CT, often combined with CTA, is highlighted for its diagnostic value in identifying inflammation and infections early, even before anatomical changes are evident. Special attention is given to the preparation protocols and imaging techniques, emphasizing the importance of patient preparation including the effects of glucocorticoids on 18F-FDG uptake, and optimal imaging protocols to enhance diagnostic accuracy. The visual and quantitative interpretation of 18F-FDG PET/CT results, along with CTA, is decisive for accurate diagnosis and management. The combination of 18F-FDG PET/CT and CTA offers a comprehensive approach for diagnosing and managing aortitis, particularly in complex cases involving infections or prosthetic grafts. This multimodal imaging strategy improves diagnostic accuracy and guides targeted treatment, leading to better patient outcomes.