Breast density and infl uencing factors

Abstract

Breast parenchyma consists of three types of tissue – skin, subcutaneous adipose tissue and functional glandular tissue. The breast itself is divided into approximately 15–18 lobes. Lobes consist of branching ductal systems which lead from the collecting ducts to the terminal ductal lobular units (TDLU). Most breast diseases – with the exception of papillomas in major ducts – arise in the TDLU. The TDLU normally regresses at menopause [1].