{HEAD ~ The method} includes acquiring {TAIL ~ the gray tone images}, and plotting a histogram of the average pixel signal intensities for selected regions of interest in each image 
includes acquiring
{ HEAD ~ The method } includes acquiring { TAIL ~ the gray tone images } , and plotting a histogram of the average pixel signal intensities for selected regions of interest in each image
HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH