Mammography

Mammography is the process of using low-dose amplitude-X-rays (usually around 0.7 mSv) to examine the human breast and is used as a diagnostic and a screening tool. There are two projective viewpoints available of the breast in mammography. The craniocaudal view (CC), where the breast is compressed horizontally and an x-ray is taken in the direction from head to toe, and the medio-lateral (ML), where the breast is vertically compressed and x-ray is taken from the side. The images included are both carniocaudal views.

During the procedure, the tissue is compressed by parallel-plate of mammography unit. Parallel-plate compression evens out the thickness of breast tissue to increase image quality by reducing the thickness of tissue that x-rays must penetrate, decreasing the amount of scattered radiation (scatter degrades image quality), reducing the required radiation dose, and holding the breast still (preventing motion blur).

Mammographic density refers to the prevalence of fibroglandular tissue in the breast versus fatty tissues as it appears on a mammogram. In the following image, Raundahl illustrates three examples of mammograms with different density
(a) Low density; (b) Medium density; (c) High density