This is demonstrated in Fig. 6 where a curved-plane reformat of a B2B-RMC image corrected for proximal coronary motion (as performed for the comparisons in Table 2) (a) and corrected for distal motion (b) are compared to the equivalent curved-plane reformat of the nav-bSSFP acquisition (c). For the

B2B-RMC images, it is apparent that the distal vessel is sharpest in (b) while the proximal vessel is sharpest in (a). In comparison, the nav-bSSFP image (c) is sharp over both proximal and distal regions, although at the expense of a 2.3-fold decrease in respiratory efficiency. This need for different respiratory motion corrections in the proximal and distal regions is emphasized in Fig. 7 which shows the beat-to-beat in-plane (x and y) and through-plane (z) respiratory translations relating to the corrected images shown in Fig. 6 (A) and (B) plotted against the corresponding selleck chemical diaphragm displacements, Proteases inhibitor as measured

with the following navigator. In this instance, the slope of the y in-plane correction vs. the superior–inferior diaphragm displacement was 0.23 in the proximal region and 0.60 in the distal region. Similarly, the corresponding slope for the in-plane x corrections was 0.039 in the proximal region and –0.31 in the distal region. An initial attempt to combine the B2B-RMC images corrected for both proximal and distal motion was performed by selectively replacing data in the vicinity of the distal artery in the proximally corrected data set with equivalent data from the distally corrected data set. Voxels in the border region between the two corrected data sets were linearly combined, resulting in a fading effect. The result of this is shown in Fig. 8 and demonstrates high clarity along the entire length of the vessel. The B2B-RMC technique can compensate for respiratory motion with near 100% respiratory efficiency using in vivo and phantom measures of vessel diameter and vessel sharpness in coronary artery imaging as quantitative

markers of performance. Data acquired in a respiratory motion phantom BCKDHA following respiratory traces obtained from healthy volunteers have demonstrated that the B2B-RMC technique can correct for a large range of translational motion. Vessel sharpness measurements are better than those obtained using conventional navigator gating with a 5-mm window, and the diameter measurements are very similar to those obtained from a stationary phantom. Even in the case of extreme respiratory motion (trace 6, Fig. 4E), the B2B-RMC technique performed well with 100% respiratory efficiency. In this instance, the respiratory efficiency using navigator gating was so low (13%) that the acquisition failed. The underestimation of the vessel diameter obtained in these experiments (2.60 mm in the stationary phantom compared to the 3.