What is 3D mammography?
Also called breast tomosynthesis, 3D mammography produces very detailed images of the breast tissue, far more detailed than the images obtained during “traditional” two-dimensional mammography. While 2D mammography is used for identifying cancers and other abnormal growths in breast tissue, it cannot detect all cancers at all stages. Very small tumors or tumors “hidden” by dense breast tissue can be difficult to detect with traditional 2D mammography. 3D mammography developed as a way to improve the imaging capabilities of mammograms, helping radiologists and other doctors identify and assess cancers while they’re very small or located in areas of the breast that are otherwise difficult to view.
The technology used in 3D mammography received FDA approval in 2011, and since then, this proven technique has been used to identify tiny, hard-to-detect cancers in millions of women, helping them get the treatment they need as early as possible.
How 3D mammography works
Like 2D mammography, 3D mammography uses X-rays to visualize the tissues of your breast. X-rays are absorbed differently, depending on the density or thickness of the tissue. As the X-rays pass through your body, the energy that escapes is measured by the X-ray device. The energy measurements are “interpreted” by the X-ray machine to produce images of the breast, with denser breast tissue and abnormal growths appearing “whiter” or brighter than the surrounding tissue.
3D mammography is performed in place of 2D imaging, while your breast tissue is compressed. During the 3D exam, an additional series of images of breast tissue is created, with each image representing a “slice” of tissue. These slices can be viewed individually for greater detail of small growth or abnormalities, or they may be reconstructed into a three-dimensional image of the tissue inside your breast. At Windsor Radiology, 3D mammograms have a near identical low radiation dose compared to 2D.
What is a diagnostic mammogram?
A diagnostic mammogram is performed when a screening mammogram reveals an area of abnormal tissue, such as lumps or masses, or after a clinical breast exam finds a lump or other suspicious findings, such as dimpling or nipple discharge. Unlike screening mammography that examines the entire breast for signs of cancer, diagnostic mammography focuses on the specific area where the abnormal findings are located. Sometimes, a digital mammogram procedure is followed up with an ultrasound exam of breast tissue or a biopsy to obtain a small sample of tissue for examination under a microscope, especially if the lump has uneven edges or appears as a starburst. In some cases, abnormal findings may be due to harmless calcifications of tissue, and no further examination is needed.
What to expect during a 3D mammography exam
The mammography machine is a box-shaped device that contains the X-ray apparatus. During your exam, you’ll stand (or sometimes sit) in front of the box while the technician positions your breast on a flat, paddle-like surface. After the breast is properly positioned, a second flat paddle will descend over the breast, compressing the breast tissue so your breast is very flat. Because breast tissue is composed of different "layers," compression is necessary to enable the X-ray to produce detailed images of each of these layers. Compression also allows the machine to visualize smaller abnormalities that might be obscured by overlapping layers of tissue, and it enables these images to be made with less radiation exposure. Plus, it helps ensure the breast is held very still so the clearest images can be captured. Once the tissue is compressed, the machine emits X-rays to capture images of your breast in two dimensions, passing back and forth in an arc shape, creating a series of images of your breast tissue that provide views from different angles. As with 2D mammography, you’ll need to hold very still during the imaging exam to ensure the clearest images are captured. Most exams take a half hour or less. After your exam, the images will be sent to one of our board-certified radiologists for interpretation, then the final report will be sent to your doctor.