Imaging for Diagnosis, Monitoring, and Outcome Prediction of Large Vessel Vasculitides

Abstract

Purpose of review: To discuss and summarize the latest evidence on imaging techniques in giant cell arteritis (GCA) and Takayasu arteritis (TAK). This is a report on the performance of ultrasound (US), magnetic resonance imaging (MRI), computed tomography (CT), 18F-fluorodeoxyglucose positron emission tomography (18-FDG-PET), and other emerging imaging techniques in diagnosis, outcome prediction, and monitoring of disease activity.

Recent findings: Imaging techniques have gained an important role for diagnosis of large vessel vasculitides (LVV). As signs of vasculitis, US, MRI, and CT show a homogeneous arterial wall thickening, which is mostly concentric. PET displays increased FDG uptake in inflamed artery walls. US is recommended as the initial imaging modality in GCA. MRI and PET/CT may also detect vasculitis of temporal arteries. For TAK, MRI is recommended as the first imaging modality as it provides a good overview without radiation. Extracranial LVV can be confirmed by all four modalities. In addition, MRI and PET/CT provide consistent examination of the aorta and its branches. New techniques such as contrast-enhanced ultrasound, PET/MRI, and auxiliary methods such as "computer-assisted quantitative analysis" have emerged and need to be further validated. Imaging has partly replaced histology for confirming LVV. Provided experience and adequate training, US, MRI, CT, or PET provide excellent diagnostic accuracy. Imaging results need to complement history and clinical examination. Ongoing studies are evaluating the role of imaging for monitoring and outcome measurement.

Keywords: 18F- fluorodeoxyglucose positron emission tomography; Computed tomography; Diagnosis; Giant cell arteritis; Imaging; Large vessel vasculitis; Magnetic resonance imaging; Outcome; Takayasu arteritis; Ultrasound.

Fig. 1

Halo sign of the common superficial temporal artery. Typical halo sign of the common superficial temporal artery, transverse scan, in a patient with newly diagnosed GCA

Fig. 2

Vasculitis of the axillary artery in giant cell arteritis (longitudinal view). Longitudinal view of the axillary artery in a patient with large vessel GCA, the intima-media complex is significantly thickened, 1.81 mm; normal < 1.0 mm

Fig. 3

Vasculitis of the common carotid artery in Takayasu arteritis. US of the common carotid artery in a patient with Takayasu arteritis. The intima-media thickness of the common carotid artery is relevantly increased (arrow). Further is the flow velocity increased, indicating a stenosis of about 50% or decreased elasticity of the wall

Fig. 4

Hybrid [11C]-PK11195 PET/CT in a patient with giant cell arteritis. Hybrid [11C]-PK11195 PET-CT and CT images. From left to right, fusion image, in the middle is PK11195 and on the right side CT images of the same giant cell arteritis patient in transverse and sagittal section. Courtesy of Professor Paolo G. Camici, Milano, Italy

Fig. 5

PET/MRI in a patient with giant cell arteritis. PET/MRI shows an inflammatory pattern with clear uptake (> liver uptake, grade 3) in vertebral arteries. a Maximum intensity projection and b fusion MR angiography/PET (arrows) associated with arterial wall thickening on: (c) MR axial T2-weighted image and (d) T2-weighted/PET fusion. Arrows indicate vertebral artery. Laurent C et al. Sci Rep. 2019 Aug 27;9(1):12388 [63] published under a CC BY 4.0 license

Fig. 6

PET / MRI in a patient with Takayasu arteritis. PET/MRI ((a) coronal PET, (b) T2-weighted image, (c) post-contrast T1-weighted image, (d) fusion MR angiography/PET, (e) fusion PET/T2-weighted image) shows an inflammatory pattern with clear uptake (grade 3) at the origin of supraaortic arteries associated with arterial wall thickening on T2-weighted image (a, arrows) and wall enhancement (b, arrows). Fusion images (c, d) show excellent co-registration of FDG uptake and MR findings. Laurent C et al. Sci Rep. 2019 Aug 27;9(1):12388 [63] published under a CC BY 4.0 license