A 3D mammogram, also known as breast tomosynthesis or digital breast tomosynthesis (DBT), is an advanced breast imaging technique. It combines multiple X-ray images to create a three-dimensional picture of the breast. This method aims to improve the detection of breast cancer and can also help identify the cause of breast concerns such as a mass, pain, or nipple discharge.
Preparing for Your 3D Mammogram
Before a 3D mammogram, patients can take several steps to help ensure a smooth and effective examination. It’s recommended to schedule the appointment during the week following a menstrual period, when breasts are less tender. Wear a comfortable two-piece outfit, as you’ll need to undress from the waist up and wear a gown.
Avoid applying deodorant, antiperspirant, powders, lotions, creams, or perfumes under the arms or on the breasts. These products can interfere with results by appearing as white spots on X-ray images. Inform the technologist about any recent breast changes, concerns, prior surgeries, hormone use, or a personal or family history of breast cancer. If you have previous mammograms from a different facility, bring them for comparison.
The 3D Mammogram Procedure
The 3D mammogram procedure is similar to a traditional 2D mammogram in many aspects. Upon entering the exam room, patients will remove clothing from the waist up and put on a gown. A technologist will position one breast on the X-ray machine’s platform.
The technologist adjusts the platform’s height and positions your head, arms, and torso for a clear view of the breast tissue. A clear plastic compression plate is then lowered to press the breast against the platform. This compression, while potentially uncomfortable, is necessary to spread out breast tissue, reduce motion blur, and capture the entire breast.
Once compressed, the X-ray arm moves in a slight arc over the breast. It captures multiple low-dose X-ray images from various angles over a few seconds. You may be asked to hold your breath briefly to minimize movement. These images are then digitally reconstructed by a computer to form a 3D volume of the breast tissue.
The process is then repeated for the other breast. The entire procedure, from check-in to completion, takes around 10 to 30 minutes, with actual compression and imaging for each breast lasting only a few seconds.
Interpreting the Images and Receiving Results
After 3D mammogram images are acquired, a computer processes them into a three-dimensional picture of the breast. A radiologist, a medical doctor specializing in interpreting imaging tests, then reviews these images. The 3D images provide multiple thin “slices” of breast tissue, allowing the radiologist to scroll through them layer by layer.
This layered view helps the radiologist examine breast tissue for abnormalities, such as masses, calcifications, or areas of irregular density. If anything concerning is identified, the radiologist may compare new images with past mammograms to look for changes over time. Following the review, the radiologist dictates the findings in a report, which is sent to the patient’s referring healthcare provider.
Patients typically receive their results within one to two weeks, though some facilities may provide them sooner. Results are commonly communicated via mail, phone, or an online patient portal. If an abnormality is found, the healthcare provider will usually contact the patient to discuss the findings and recommend follow-up tests, such as additional imaging (e.g., ultrasound or MRI) or a biopsy.
How 3D Mammography Differs from 2D
The fundamental distinction between 3D mammography (tomosynthesis) and traditional 2D mammography lies in their imaging approach and the resulting image detail. A conventional 2D mammogram captures two flat, two-dimensional X-ray images of each breast (top-to-bottom and angled side-to-side). This method, while effective, can lead to overlapping breast tissue, which may obscure abnormalities or create false concerns.
In contrast, 3D mammography involves the X-ray arm moving in an arc over the compressed breast, acquiring multiple low-dose images from various angles. These “slice” images, often around 300 per breast, are digitally reconstructed to create a 3D volume of the breast tissue.
This layered view allows radiologists to examine the breast tissue in thin, one-millimeter sections, effectively “peeling back” layers. This capability helps reduce tissue overlap, providing a clearer and more detailed view of breast structures. While the patient experience, including breast compression, is largely similar to a 2D mammogram, the technological difference in image acquisition and reconstruction significantly enhances the radiologist’s ability to distinguish between normal breast tissue and potential abnormalities.