In 1 study, the preferred scan time for optimal vessel wall inflammation was 2.5 hours with a target glucose level of <7.0 mmol/L (<126 mg/dL) [12]. In patients with coronary artery involvement/suspected coronary artery vasculitis, myocardial suppression should be achieved via diet, and ECG-gated images should be obtained [13]. Recently, there has been emerging literature describing FDG uptake in the head and neck arteries, particularly in the temporal and maxillary arteries, which could aid the simultaneous diagnosis of c-GCA and LV-GCA [14,15]. MRI and MRA In LVV, body MRI or MR angiography (MRA), including the chest, abdomen, and pelvis, can be performed to assess vasculitic changes [16]. MRI and MRA sequences are the following: T2-weighted fast spin-echo sequence or inversion recovery sequences, such as short-tau inversion recovery to display edema in the vessel wall; ECG- gated rapid 3-D T1-weighted spoiled gradient-echo pulse sequences can be used for MRA with gadolinium-based agents and maximum-intensity projection reformats; and postcontrast T1-weighted imaging with fat suppression (preferably using the Dixon technique) can be acquired throughout the body. Recently, new sequences have been introduced for LVV diagnosis, such as navigated T1-weighted 3-D black-blood fast turbo spin-echo sequence, which can acquire pre- and postcontrast isotropic 3-D images [17,18]. Last, the ECG-triggered balanced steady- state free-precession sequence provides additional information regarding the aortic root. Gadolinium injection through the veins can create susceptibility artifact along the axillary and subclavian arteries; therefore, maximum- intensity projection images should be examined carefully, and delayed images should be correlated [19]. There is a growing body of literature on high-resolution cranial MRI of the superficial cranial arteries for the diagnosis of c-GCA [20,21].
Noncerebral Vasculitis. In 1 study, the preferred scan time for optimal vessel wall inflammation was 2.5 hours with a target glucose level of <7.0 mmol/L (<126 mg/dL) [12]. In patients with coronary artery involvement/suspected coronary artery vasculitis, myocardial suppression should be achieved via diet, and ECG-gated images should be obtained [13]. Recently, there has been emerging literature describing FDG uptake in the head and neck arteries, particularly in the temporal and maxillary arteries, which could aid the simultaneous diagnosis of c-GCA and LV-GCA [14,15]. MRI and MRA In LVV, body MRI or MR angiography (MRA), including the chest, abdomen, and pelvis, can be performed to assess vasculitic changes [16]. MRI and MRA sequences are the following: T2-weighted fast spin-echo sequence or inversion recovery sequences, such as short-tau inversion recovery to display edema in the vessel wall; ECG- gated rapid 3-D T1-weighted spoiled gradient-echo pulse sequences can be used for MRA with gadolinium-based agents and maximum-intensity projection reformats; and postcontrast T1-weighted imaging with fat suppression (preferably using the Dixon technique) can be acquired throughout the body. Recently, new sequences have been introduced for LVV diagnosis, such as navigated T1-weighted 3-D black-blood fast turbo spin-echo sequence, which can acquire pre- and postcontrast isotropic 3-D images [17,18]. Last, the ECG-triggered balanced steady- state free-precession sequence provides additional information regarding the aortic root. Gadolinium injection through the veins can create susceptibility artifact along the axillary and subclavian arteries; therefore, maximum- intensity projection images should be examined carefully, and delayed images should be correlated [19]. There is a growing body of literature on high-resolution cranial MRI of the superficial cranial arteries for the diagnosis of c-GCA [20,21].