Comparison of native high-resolution 3D and contrast-enhanced MR angiography for assessing the thoracic aorta. (7th January 2014)

• Record Type: Journal Article
• Authors: von Knobelsdorff-Brenkenhoff, Florian; Gruettner, Henriette; Trauzeddel, Ralf F.; Greiser, Andreas; Schulz-Menger, Jeanette
• Is Part Of: European heart journal. Volume 15:Number 6(2014:Jun.)
• Page Start: 651
• Page End: 658
• Publication Date: 2014-01-07
• Subjects: Aorta -- Magnetic resonance -- Angiography -- Native; Cardiovascular system -- Imaging -- Periodicals; Heart -- Imaging -- Periodicals; 616.10754
• DOI: 10.1093/ehjci/jet263
• Languages: English
• ISSNs: 2047-2404

Abstract

Abstract: Aims: To omit risks of contrast agent administration, native magnetic resonance angiography (MRA) is desired for assessing the thoracic aorta. The aim was to evaluate a native steady-state free precession (SSFP) three-dimensional (3D) MRA in comparison with contrast-enhanced MRA as the gold standard. Methods and results: Seventy-six prospective patients with known or suspicion of thoracic aortic disease underwent MRA at 1.5 T using (i) native 3D SSFP MRA with ECG and navigator gating and high isotropic spatial resolution (1.3 × 1.3 × 1.3 mm 3 ) and (ii) conventional contrast-enhanced ECG-gated gradient-echo 3D MRA (1.3 × 0.8 × 1.8 mm 3 ). Datasets were compared at nine aortic levels regarding image quality (score 0–3: 0 = poor, 3 = excellent) and aortic diameters, as well as observer dependency and final diagnosis. Statistical tests included paired t -test, correlation analysis, and Bland–Altman analysis. Native 3D MRA was acquired successfully in 70 of 76 subjects (mean acquisition time 8.6 ± 2.7 min), while irregular breathing excluded 6 of 76 subjects. Aortic diameters agreed close between both methods at all aortic levels ( r = 0.99; bias ± SD −0.12 ± 1.2 mm) with low intra- and inter-observer dependency (intraclass correlation coefficient 0.99). Native MRA studies resulted in the same final diagnosis as the contrast-enhanced MRA. The mean image quality score was superior with native compared with contrast-enhanced MRA (2.4 ± 0.6 vs. 1.6 ± 0.5; P < 0.001). Conclusion: Accuracy of aortic size measurements, certainty in defining the diagnosis and benefits in image quality at the aortic root, underscore the use of the tested high-resolution native 3D SSFP MRA as an appropriate alternative to contrast-enhanced MRA to assess the thoracic aorta.