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.
Image example of the four descriptive breast density categories for mammography defined by the fifth edition of the ACR BI-RADS atlas: ACR-A = the breasts are almost entirely fatty; ACR-B = there are scattered areas of fibroglandular density; ACR-C = the breasts are heterogeneously dense, which may obscure small masses; and ACR-D = the breasts are extremely dense, which lowers the sensitivity of mammography.
