Breast tomosynthesis is a relatively new 3D (three-dimensional) imaging technique that represents the latest technological innovation in mammography and breast cancer screening. 3D mammography can detect many more breast cancers than conventional radiography and reduce the number of misdiagnoses!
How does it work?
Conventional mammography corresponds to breast radiography, a simple rectilinear projection of mammary tissue crossed by X-rays on a radiological plate. Thus, a mammogram makes it possible to obtain images and to identify possible anomalies of the mammary tissues. One of the disadvantages of conventional mammography is the superposition of breast tissue on the projected image. This phonomene is all the more important and inconvenient for the interpretation of the examination as the breasts have a denser radiological texture (densities C and D).
Like a 2-D mammogram, a 3-D mammogram is an X-ray. It is also an anatomic test, which means cancer is detected based on changes in how the breast anatomy looks. Rather than an image that is formed from pictures taken from top to bottom and side to side like a 2-D mammogram, a 3-D mammogram takes multiple pictures of the breast. With the 3-D mammogram, the breast tissue can be analyzed layer by layer.
This new technology allows to obtain much more detailed and highly targeted images of the breast. They are used to produce a series of cuts of a millimeter thick which then allow the 3D reconstruction of the breast tissue. Radiologists clearly identify the characteristics of breast structures and see areas that remain unclear with 2D mammography, which may indicate a tumor but also conceal one.
Compared to 2D mammography, 3D digital tomosynthesis mammography increases the detection rate of invasive mammary tumors by 41% and screening for all breast cancers by 29%.
Note that getting a 3-D mammogram feels the same as a standard mammogram. The breast is compressed and X-rays pass through the breast to make pictures of your breast tissue.
Breast tomosynthesis, like conventional mammography, uses X-rays, which are ionizing radiation. Radiation doses are cumulative and carry risks that can not be avoided. Mammograms are only performed when the benefit of the examination is superior to the potential risks. Mammograms are performed with relatively small doses of X-rays.
The moment when breast cancer is discovered determines the chances of survival of the patient, hence the importance for women from their 40’s to have an annual mammogram.