Vascular imaging as an endpoint in clinical trials of giant cell arteritis

Giant cell arteritis (GCA) is a form of large vessel vasculitis that can affect the head and/or neck vessels as well as the aorta and its major branches. Vascular imaging techniques like 18Ffluorodeoxyglucose positron emission tomography (FDG-PET), magnetic resonance angiography (MRA), and ultrasound (US) are gaining significant attention as potential endpoints in clinical trials of GCA. Imaging is crucial not only for diagnostic purposes, but also for potential accurate and reliable assessment of disease activity, especially when evaluating treatment response to novel targeted therapies in GCA. Imaging scoring systems can assist with tracking changes in vascular inflammation and damage over time. Vascular imaging is also a valuable tool for detection of subclinical inflammation and/or vascular remodelling that is not possible with clinical assessment. Furthermore, vascular imaging might predict angiographic progression. In this article, we review the utility of vascular imaging as an endpoint in GCA clinical trials highlighting the challenges that are associated with its application.