Giant cell arteriitis (GCA) with typical affection of the superficial temporary artery is within a standard European population the most commonest vasculitis. Thus biopsy is the so called "gold standard", assessment with high resolution contrast enhanced and fat saturated T1- MRI is possible and can also be used for monitoring within anti-inflammatory / immunsuppressive therapy. Especially MRI allows simultaneously assesment of all superficial artery segments.
A symmetrical and simultaneous vascular inflammation of superficial cranial arteries is the typical involvement pattern. MRI imaging sings may vanish after 5-7 days of systemic anti-inflammatory therapy with steroids.
For ranking of mural contrast enhancement, the following four-point scale proposed by Bley et. al. can be used:
-, no enhancement; +, slight mural enhancement; ++, prominent mural enhancement; and +++, strong mural enhancement, including perivascular tissue.
For the wall thickness the cuttoff between unaffected and inflamed arteries 0.6 to 0.7 mm.