Figure 1

Flow jet angle estimation using 4D flow. Panel A shows the aorta segmentation obtained from 4D flow angiography. Aorta segmentation (gray) was used to compute volume centerline (blue line). Jet shear layer detection (JSLD) was computed from 4D flow data, 3D JSLD structure (red), corresponding to vena contracta region, was obtained by normalizing JSLD. White line: aortic valve location; Red lines: sections of 3D JSLD structure; Yellow arrow: centerline vector; Orange line: 3D JSLD center of mass vector. Panel B shows a view from the top of the aortic valve at vena contracta region, a lateral view of vena contracta region with schematic lines for aortic valve location, 3D JSLD structure, centerline vector and 3D JSLD center of mass vector. Panel C shows the workflow for computing transvalvular flow jet angle from 4D flow data. Panel D shows a comparison of patient's groups. †: significant difference with MAA<35 mm; ‡: significant difference with 35 mm<MAA<45 mm; MAA: Mid ascending aorta diameter.