Figure 1.

Example single-subject graph clustering masks overlaid on the respective subject's SWI. Red areas indicate voxels within the venous voxel mask gained from graph clustering, each row showing data from a different subject. Structures seen in the graph clustering maps tend to reflect veins seen in SWI. Note that the delineation of those veins in SWI and the voxels in the EPI influenced by the signal as identified from the BOLD EPI itself can deviate slightly. Slices were selected to contain larger veins running along the slice orientation in the SWI.