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. Summary 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.

Imaging Tests in the Early Diagnosis of Giant Cell Arteritis

“…These criteria have been of great help in the identification of patients with the classic cranial symptoms of GCA and, therefore, temporal artery biopsy has been considered, for many years, as the gold standard in confirming the diagnosis of GCA [3]. However, ultrasound (US) of the temporal arteries has emerged as an alternative method to detect inflammatory changes in the vessel wall without the need for biopsy [7][8][9]. In this sense, this imaging technique has progressively gained the support of physicians for use in the early diagnosis of GCA.…”

“…Furthermore, the advent of other imaging techniques has made it possible to identify the presence of inflammatory vasculitic changes in the aorta and other extracranial vessels of patients with GCA [10][11][12][13][14]. Imaging techniques such as magnetic resonance imaging (MRI), computed tomography (CT), 18F-fluorodeoxyglucose (FDG), positron emission tomography (PET)/CT, and US have been shown to be essential for identifying a subset of patients who present with extracranial involvement without the classic pattern of cranial manifestations of GCA [8,9,15]. Extracranial LVV-GCA often presents with non-specific manifestations, such as refractory polymyalgia rheumatica (PMR) and constitutional symptoms [10,13].…”

Development and Proof of Concept of a Low-Cost Ultrasound Training Model for Diagnosis of Giant Cell Arteritis Using 3D Printing

“…It is patient-friendly, reproducible, and repeatable. It can be used in fast-track clinics offering appointments for patients within 24 h, to rapidly confirm or exclude the diagnosis of suspected GCA [ 23 ].…”

“…Designing a suitable vessel model and finding the perfect gelatine did take us a total of 12 months, as we struggled with different materials and 3D printers. However, we were finally able to 3D print a standardized artery model of the axillary and temporal artery, with either normal or pathological IMT changes fulfilling the OMERACT definitions [ 5 ] and displaying typical IMT changes [ 23 ]. When we tested the four models on two experienced sonographers in vascular ultrasound in GCA, the intra-class coefficient of normal and pathological temporal and axillary arteries in GCA were excellent for the diagnosis of GCA.…”

Role of temporal artery resection in Horton's arteritis (Review)

“…Brain magnetic resonance imaging (MRI) examination is mandatory to rule out a brain pathology that causes symptoms such as headache or sudden visual loss ( Fig. 6 ) ( 21 , 22 ).…”