Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
The Grayscale Histogram of ROI. Horizontal axis denotes a grayscale (G), and vertical axis a number of voxels. G = 0 is the background color of black; G = 255 the color of white. From the grayscale distribution corresponding to the tissues in Figure 3, we can define the grayscale range for fat, parenchyma, and tumor tissues.
