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2D digital mammography and Tomosynthesis or 3D digital mammography

By: Donna Cameron, RN, CBCN, Associate Director of Outpatient Women’s Services

Early detection is the key to aid in the prevention of more advanced breast cancers. When breast cancers are found early, the cancer is so small that it is not even felt, the breast cancer is more treatable the early it is found and results in better outcomes (Newton & Lee, 2020). Mammography is a method used for early detection. Since 1990 there has been a 30% decrease in breast cancer deaths largely due to the use of screening mammography (Lee, et al., 2010).

Mammography is considered the best available method to screen for breast cancer; using low dose x-ray which creates images of the breast. Mammography can find cancer in areas of the breast before it is felt by a healthcare provider during an annual exam, and usually one to two years before found during a breast self-exam. There are two types of mammography procedures: screening and diagnostic. A screening mammogram is generally done annually when there are no lumps felt by the patient and/or any other breast changes. A diagnostic mammogram is done when there are reported breast changes and/or if an area of abnormality is seen on the screening mammogram. Diagnostic mammography is more involved, meaning more images are taken of the breast (Newton & Lee, 2020). In Connecticut, screening mammograms are covered 100% by insurance. A co-pay is usually involved with a diagnostic mammogram and is applied to the insurance deductible.

There are also 2 different mammography machines used: 2D digital mammography machine and 3D digital mammography machine. What is the difference than between 2D and 3D mammography? Both 2D and 3D mammography uses the same technology of low doses of x-rays but result in different images taken. The difference can be compared to a circle and a ball. The 2D mammogram images resemble a flat circle on a paper. The 3D digital mammography takes multiple images from many angles of the breast which creates a 3-dimensional picture or ball. The breast is positioned in the same way as with 2D mammography. The machine does all the work by moving like an arc over the breast (“Digital Tomosynthesis,” 2016, Lee, et al., 2010).

3D digital mammography is new in the world of breast imaging. Studies have found that 3D digital mammography is beneficial for women with dense breast tissue and reduces call back examinations. 2D digital mammography will still detect a breast cancer early, the 3D digital mammography may just have found it a little sooner (Newton & Lee, 2020, Wojciechowski, 2019).

ECHN has recently acquired these 3D digital mammography machines at the Women’s Center for Wellness and Tolland Imaging Center. 2D digital mammography is still available at Manchester Memorial Hospital and Rockville General Hospital.

To support early detection, ECHN offers free mammograms, pap tests and heart disease screenings to women between the ages of 30 – 64 who have limited income, no health insurance or have a high insurance deductible ($1,000 or more). Click here to see if you qualify.


Digital Tomosynthesis. (2016, June 23). Retrieved from https://breastcancer.org/symptoms/testing/types/dig_tomosynth

Lee, C. H., Dershaw, D., Kopans, D., Evans, P., Monsees, B., Monticciolo, D., …Burhenne, L. W. (2010). Journal of American College of Radiology, 7, 18-27. doi:10.1016/j.jacr.2009.09.022

Newton, E., & Lee, M. C. (2020). Breast Cancer Screening: Practice Essentials, Guidelines, Self- examinations and Clinical Examinations, Mammography, Ultrasonography, Magnetic Resonance Imaging. Mescape. https://emedicine.medscape.com/article/1945498-print.

Wojciechowski, B. (2019, August 16). What my patients are asking: The difference between 2D and 3D mammograms [Audio podcast]. Retrieved from https://breastcancer.org/community/podcasts/3d-mammography20190809