Table 1.
Protocol parameters used for the acquisitions.
Fig 1.
Comparison of the image quality before and after the sequence modifications.
An axial in-vivo image of the upper mouse abdomen before (left side) and after sequence modifications (right side) is shown. Images a and c show the magnitude reconstruction of the acquisitions, b and d the corresponding flow images for one direction. One can see multiple ghosts (exemplarily shown with red arrows) in the phase encoding direction (top to bottom) in the images of the unmodified sequence (left side). These artifacts are removed when using dummy scans during respiration (right side).
Fig 2.
Mean flow over the cardiac cycle.
Flow over the cardiac cycle for four evaluation planes placed at specified locations is shown on the right. Flow is highest in the ascending aorta (AAo). The curves show the mean value of all subjects and their standard error of the mean as error bars. One can observe a trend towards lower flow velocities (plane 1 towards plane 4) as expected and longer time to peak flow durations.
Fig 3.
Mean axial wall shear stress over the cardiac cycle.
Mean axial wall shear stress over the cardiac cycle for four evaluation planes placed at specified locations is shown on the right. The highest wall shear stress can be observed in the third plane. The curves show the mean value of all subjects and their standard error of the mean as error bars. The lowest mean axial wall shear stress occurs in the ascending aorta.
Fig 4.
Streamline representation of the blood velocities during systole.
a) Streamline representation of the velocities of one mouse during peak systole. Streamlines are generated from four emitter planes placed perpendicular to the aorta as shown in (c). Streamlines are color coded with the magnitude of the velocity as displayed in the color bar. The isosurface in this image was calculated as speed-sum-of-squares isosurface from the velocity data. One can identify regions of high velocities and low velocities. The vessel lumen is equally filled. Streamlines continue even in the small branches of the aorta. Velocities are lower in the aortic branches than in the aortic root. Supplementary animation S2 Fig provides extended streamline visualization from multiple viewing angles. b) Streamline representation of the velocities of one mouse during peak systole from Bovenkamp et al [5] figure 6 (clipped). “Blood flow visualization with vector magnitude-encoded streamlines in the cardiovascular system of a mouse at 13.76 ms after R wave of the ECG”. c)Visualization of the used emitter planes for the streamlines in the aortic arch. d)Unmasked streamlines are shown that leave the isosurface. The isosurface is shown opaque in order to easily identify aberrant streamlines. e)Placement of the ROIs for SNR analysis.
Fig 5.
Pathline visualization of the blood flow in the aorta during systole.
a) Pathline visualization during systole generated in early systole from two emitter planes perpendicular to the vessel. The emitted pathlines continue into the brachiocephalic trunk, left common carotid artery and the left subclavian artery. The pathlines are masked by a speed-sum-of-squares isosurface. A pathline animation over the cardiac cycle is shown in the supplementary animation S3 Fig. b) Visualization of the used emitter planes for the pathlines in the aortic arch. c) Unmasked pathlines are shown that leave the isosurface. The isosurface is shown opaque to easily identify aberrant pathlines.