Biodistribution of labeled ASCs in a rat injected via left ventricle. Maximum intensity projection of whole-body PET image (a) from a rat injected with double-labeled ASCs via left ventricle (25 μg/ml SPIO and 1.34 MBq FDG). The image is reconstructed with MAP algorithm and attenuation corrected. The arrow heads point out to the lungs (solid) and the heart (dashed). The panel on the right (b) represents the image with the heart at the center of field of view. It is evident that a portion of the cells are retained in the myocardium, with some in the lungs.