Fig. 3: Setup and results for perfusion source mapping of individual superior veins.

a A sagittal image showing the placement of the axial imaging slice and saturation band. b From the dataset, different vessels that flow through the imaging slice can be identified by examining the perfusion source map energy of target image voxels and detecting peaks. The detected peaks are overlaid with white ROIs on the image. Four color-coded ROIs are selected out of these regions, each containing a different superior vein that drains into the slice. c The color-coded draining veins overlaid on a 3D Quantitative Susceptibility Mapping (QSM) venogram. Anatomical orientations for the QSM-venogram are labeled as follows: Anterior (A), Posterior (P), Superior (S), Inferior (I), Left (L), and Right (R). d 2D perfusion maps from each ROI, overlaid on the coronal sections of QSM-venograms, showing the ability to trace the sources of blood. Over short mixing times, blood remains in the large vein. For longer times, the diffused maps indicate blood coming from smaller veins and potentially from capillary beds and surrounding tissue. The coronal projection of the venous territory, obtained from the perfusion source maps, is shown with dashed contours for each vein. Source data are provided in ref. ⁵⁴.