French recommendations for the use of imaging in giant cell arteritis

We aimed at developing French recommendations for the use of imaging modalities in giant cell arteritis (GCA).

A systematic literature review was conducted to identify evidence regarding the use of Doppler ultrasound (DUS), magnetic resonance imaging (MRI), computed tomography (CT) angiography and [¹⁸F]-fluorodeoxyglucose positron emission tomography (FDG-PET/CT) for diagnosing, monitoring, and predicting the outcome of GCA. The task force, composed of 23 physicians, proposed the recommendations through an iterative process based on evidence and expert opinion, with consensus determined by anonymous voting.

The task force recommends an early imaging test for patients with suspected GCA. The recommendations propose DUS as the first-line imaging test for all patients with suspected GCA. FDG-PET, cranial MRI, aortic MRI and CT-scan can be used as alternative methods to assess the cranial and/or extracranial arteries, providing imaging evidence of vasculitis. Imaging of large vessels is also useful for determining prognosis and follow-up procedures. In patients with suspected visual GCA, ophtalmoscopic fundus examination, optical coherence tomography (OCT) and retinal angiography should be performed in emergency. Although imaging is not routinely recommended for follow-up, it may be used to assess a persistent vascular inflammatory process in patients suspected of relapse, especially when inflammatory biomarkers are unreliable. In this situation, vascular activity scores are recommended for follow-up. Imaging may be used to monitor long-term structural damage, particularly in areas where vascular inflammation has previously been detected.

The recommendations offer guidance on the use of imaging for diagnosing and evaluating patients with GCA.