Toward comparability of coronary magnetic resonance angiography: proposal for a standardized quantitative assessment.

A method is proposed for the quantitative assessment of coronary magnetic resonance angiography (MRA) acquisitions. The method is based on four parameters: signal-to-noise ratio (SNR); contrast-to-noise ratio (CNR); vessel length; and vessel-edge definition. A pig model (n=7) was used to illustrate the proposed quantitative analysis method. Three-dimensional gradient-echo coronary MRA was performed with and without exogenous contrast enhancement using a gadolinium-based blood-pool contrast agent (Vistarem, Guerbet, Aulnay-Sous-Bois, France). The acquired images could be well differentiated based on the four parameters. The SNR was calculated as 9.0+/-1.4 vs 10.4+/-2.1, the CNR as 6.2+/-0.8 vs 8.2+/-0.9, the vessel length as 48.2+/-11.6 vs 86.5+/-13.8 mm, and the vessel-edge definition as 4.9+/-1.5 vs 7.7+/-3.4. Different coronary MRA techniques can be evaluated objectively with the combined use of SNR, CNR, vessel length, and vessel-edge parameters.