One 20-week old swine was excluded from analysis due to poor image quality. For nine swine pulmonary vascular geometries were segmented from 3D rotational angiography (3DRA: voxel size 0.47mm), and for one the geometry was segmented from multi-slice computed tomography (MSCT: voxel size 0.7mm). For two 5-week old swine and one 10-week old swine geometries were segmented from phase-contrast magnetic resonance angiography (PC-MRA: voxel size 1.25mm) due to artifacts present in datasets from the higher spatial resolution imaging modalities. Geometries were segmented manually using a combination of the software packages Simvascular28 (link), Mimics (Materialize, Leuven), and 3-matic (Materialize, Leuven). All inlet and outlets were trimmed to ensure that these faces were perpendicular to the vessel centerlines. Representative geometries for 5-week, 10-week, and 20-week swine are shown in Figure 1 along with a PC-MRA segmentation to show the limited distal vascular that could be seen with PC-MRA.