Imaging description

Takayasu's arteritis (TA) is clinically classified as a large-vessel vasculitis, as it largely affects the aorta and its major branches and the pulmonary arteries. TA is a disease of young patients, and is often imaged using MRI to avoid repeated radiation exposure. Typical imaging findings include arterial wall thickening early in the disease (Figure 51.1), followed by stenosis, occlusion, and aneurysmal dilatation in the late phase [1–3]. The most commonly involved vessels are the proximal subclavian and carotid arteries (Figure 51.2) [1]. The pulmonary arteries are affected in approximately 50–80% of cases and may demonstrate mural calcification late in the disease [2]. The lesions of TA are positive on FDG-PET (Figure 51.3), but the utility of PET in monitoring disease activity has yet to be conclusively proven [1].

Importance

Early TA causes nonspecific constitutional symptoms. Recognition of arterial wall thickening may aid early diagnosis. Late in the disease, symptoms are related to vascular occlusion and imaging is useful in evaluating vascular patency and in surgical planning.