Gated thoracic magnetic resonance angiography at 3T: noncontrast versus blood pool contrast

Abstract

Both noncontrast and contrast-enhanced approaches to gated thoracic magnetic resonance angiography (MRA) for aortic root evaluation have been reported at 3T. We compare qualitative and quantitative image quality measures for the two approaches, and assess the reproducibility of standard aortic measurements. Respiratory and cardiac gated MRA of the chest was performed at 3T in 45 patients: 23 after administration of iron-based blood pool contrast, and 22 without contrast. Image quality was assessed with a 5-point Likert scale, vessel lumen-to-muscle contrast ratios, and vessel wall sharpness. Two reviewers measured the ascending aorta diameter and valve annulus area. Interrater agreement was assessed using Bland–Altman plots and coefficient of variation (CV). Qualitative image quality was better with blood pool contrast in all principal vessels of the chest (mean Likert of 4.20 ± 0.79 vs. 2.60 ± 0.77, p < 0.001). Quantitative assessment was also improved with higher contrast ratios in all vessels (5.26 ± 3.3 vs. 1.90 ± 0.53, p < 0.001), and greater sharpness of the aortic annulus and ascending aorta (0.70 ± 0.16 vs. 0.56 ± 0.14 mm−1, p < 0.001, and 0.87 ± 0.16 vs. 0.62 ± 0.16 mm−1, p = 0.008, respectively). Reproducibility of measurement was marginally better for the ascending aorta diameter (CV of 2.80 vs. 3.23%), but substantially increased for the aortic valve annulus area with blood pool contrast (CV of 4.93 vs. 7.32%). The use of a blood pool contrast agent for gated thoracic MRA improves image quality compared to a noncontrast technique, and provides more reproducible measurements of the aortic valve annulus area.

Ferumoxtran-10-enhanced 3-T Magnetic Resonance Angiography of Pelvic Arteries: Initial Experience

“…These findings are comparable to data for ferumoxytol, another USPIO agent with promising results for MRA [21][22][23]. Ferumoxytol has even higher relaxivity (r 1 = 15 mM À1 s À1 at 1.5 T) than ferumoxtran-10 (r 1 = 9.9 mM À1 s À1 at 1.5 T).…”

Contrast-enhanced MR Angiography without Gadolinium

“…The work by Stoumpos et al adds to the growing body of literature on the off-label use of ferumoxytol in vascular imaging. Their quality images and positive results are consistent with reports from other investigators for imaging aortic disease (3,4), central veins (5), pelvic veins (6), and complex anomalies.…”

Cardiovascular imaging 2018 in the International Journal of Cardiovascular Imaging

“…Diffusion-weighted CMR was found to be comparable to PET-CT in the follow-up of patients with chronic periaortitis [72]. The use of a blood pool contrast agent for gated thoracic MRA at 3 T was found to improve the image quality compared with a non-contrast technique and provided more reproducible measurements of the aortic annulus area [73].…”