The issue of improved diagnosis of both rheumatic diseases of the elderly and aortic diseases does not lose its relevance. In terms of aortic aneurysms, dissection and ruptures and their attended pathogenesis, both inflammation and structural wall damages may be detected with imaging methods whose role is vital. A number of international guidelines deal with the management of polymyalgia rheumatica, giant cell arteritis, or aortic aneurysms. Aortitis is associated with up to 40 % of polymyalgia rheumatica’s cases. The clinical suspicion of aortitis is based on the detection of blood pressure and pulse asymmetry, aortic regurgitation murmur, vascular bruits, as well as persistent polymyalgia rheumatica or inflammatory dorsalgia, pelvis or leg pain. In 2020, the positron emission tomography/computed tomography’s use is approved by the Italian Society for Rheumatology for the diagnosis of vasculitis attended by polymyalgia rheumatica at the secondary healthcare level and by the European Headache Federation for the diagnosis of large vessel giant cell arteritis in the neurological practice. A review of the guideline by the European Association of Nuclear Medicine, the Society of Nuclear Medicine and Molecular Imaging, and the American Society of Nuclear Cardiology (2018) was performed in terms of positron emission tomography with fluorodesoxyglucose combined with computed tomography (angiography) imaging in large vessel vasculitis and polymyalgia rheumatica. It is further compared with the clinical guidelines, other guidelines by the societies of nuclear medicine and new scientific data. Both procedure and patient’s preparation for examination are decribed. The criteria for assessing vasculitis proposed for either clinical practice or clinical studies are considered, as well as the factors influencing the test results and their interpretation (such as atherosclerosis, diabetes, age, body mass index, glucemia’s and acute phase markers’ levels). The guideline substantiates the benefit of both positron emission tomography’s use and its combination with computed tomography to detect extracranial vasculitis, as well as the value of performing computed tomography-angiography at different stages of the disease. There is a need to strengthen evidence on both standard time of fluorodesoxyglucose exposure and the benefit of combining positron emission tomography with computed tomography-angiography, in particular for detection of vasculitis relapses. Finding a consensus for early test’s performing is needed, as well as its score standardization, ensuring reimbursement and implementation of new imaging techniques for the cranial vessels. In the future, the evidence-based approach to managing vasculitis will be supplemented by teranostics.