Evaluating tissue characteristics including identification of injured tissue is provided by obtaining a first image of tissue including a region of interest from a first acquisition, for example, after administration of a contrast agent, and obtaining a second image of the tissue including the region of interest during a second, subsequent acquisition, for example, after administration of a contrast agent. A global characteristic of the region of interest of the first image and of the second image is determined to allow a comparison of the global characteristic of the first image and the second image to determine a potential for a change in global tissue characteristics. Such a comparison may include comparison of mean, average characteristics, histogram shape, such as skew and kurtosis, or distribution of intensities within the histogram.
