Giant cell arteritis (GCA) is the most frequent vasculitis in patients above 50 years of age.
The disease has limited mortality, mostly due to the development of aortic aneurysms, leading
to dissection and rupture. The probability to develop this complication is 17 x higher at the
level of the thoracic aorta and 2,4 x at the level of the abdominal aorta in patients with
GCA when compared with a control group. Therefore, follow-up of the aortic diameter in
patients with GCA is part of good clinical practice. Previous retrospective research showed a
link between FDG-uptake at the level of the thoracic aorta, on positron-emission-tomography
(PET) at the time of diagnosis, and the increase of diameter and volume of the thoracic aorta
during follow-up (on computed tomography (CT)).
The purpose of this prospective study is to follow-up on the aortic diameter, and to
correlate these measures with FDG-PET uptake at diagnosis. Ideally, this would allow us to
define a group of patients at high risk to develop an aortic aneurysm, already at the time of