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.
Examples of images with different image quality. Overall image quality was visually assessed using a 3-point scale (good, no artifact; moderate, minor artifacts but the image is diagnostic; poor, major artifacts with the image being non-diagnostic).
