Fig. 4.
A comparison between T2-wighted imaging (T2W), mean diffusivity (MD), restricted diffusion imaging (RDI), and histopathological quantification of cell density, macrophage, and red blood cell. A total of 6 animals, including one sham animal (#1), are presented, and each row corresponds to the same animal specimen. The high-value regions in T2W images indicate tissue edema, whereas the low-value regions are due to hemorrhagic necrosis. . The decreased values in MD may be due to the restricted diffusion caused by inflammation, but the contrast is not good enough to delineate the inflammatory regions because hemorrhagic necrosis also causes decreased values in the MD map. By contrast, RDI shows a pattern consistent with the cell density obtained from histopathological quantification. The high-value regions match well with the high cell density regions, and the low-value region matches well with hemorrhagic necrosis.