A 3D mammogram, also known as breast tomosynthesis, is an advanced breast imaging method for early cancer detection. It provides a comprehensive view of breast tissue, enhancing diagnostic accuracy.
Understanding 3D Mammography
Breast tomosynthesis, or 3D mammography, differs from conventional 2D mammography in how it captures and presents breast tissue information. While a standard 2D mammogram produces a single, flat image, a 3D mammogram creates multiple “slices” or layers. This allows specialists to view breast tissue in greater detail, reducing overlapping tissues that can obscure potential abnormalities in 2D images.
The Science Behind the Scan
A 3D mammogram involves an X-ray arm that moves in an arc over the compressed breast. The machine acquires multiple low-dose images from various angles. These images are then digitally processed by a computer, which reconstructs them into a series of thin, high-resolution “slices,” often as thin as 1 millimeter. Radiologists can view these individual slices separately or compiled into a 3D volume, examining the breast tissue layer by layer.
Why 3D Mammography is Preferred
3D mammography offers several advantages over traditional 2D imaging, improving breast cancer detection rates. It is particularly beneficial for individuals with dense breast tissue, where both dense tissue and potential cancers appear white on a mammogram, making abnormalities harder to distinguish in a 2D image. By providing layered images, 3D mammography helps radiologists differentiate between overlapping normal tissue and actual abnormalities. Studies indicate that 3D mammography can detect a higher percentage of cancers, with some research showing improvements in detection by 25% to 40% compared to 2D mammograms.
This enhanced clarity also leads to a reduction in false positives, meaning fewer individuals are called back for additional imaging due to suspicious findings that turn out to be benign. Reducing these callbacks helps alleviate patient anxiety and avoids unnecessary further testing. Earlier detection of cancers can lead to more treatment options and improved outcomes.
What Happens During a 3D Mammogram
The patient experience during a 3D mammogram is similar to that of a traditional 2D mammogram. The breast is positioned and compressed between two plates to spread out the tissue, which is necessary for clear image acquisition and to minimize radiation exposure. During the imaging process, the X-ray machine’s arm moves in a slight arc over the breast, taking multiple images. The imaging time per view might be a few seconds longer than a 2D scan, but the overall procedure typically takes about 10 to 30 minutes.
Technologists ensure patient comfort, and some facilities offer features like comfort paddles or allow patients to control compression levels. Patients are advised to avoid wearing deodorant, antiperspirant, or lotion on the day of the exam, as these products can interfere with image results.
Addressing Common Concerns
A common concern regarding 3D mammography is radiation exposure. While a 3D mammogram typically involves a slightly higher radiation dose than a 2D mammogram, it remains within the safety limits established by regulatory bodies like the FDA. A 3D mammogram might expose an individual to 0.5–1 mSv of radiation, which is comparable to a few months of natural background radiation exposure. The benefits of improved cancer detection outweigh this minimal increase in radiation.
Patient comfort during the procedure is similar to 2D mammography, as both require breast compression. Advancements in technology aim to make compression more tolerable. Accessibility and insurance coverage for 3D mammograms have improved, with many insurance plans now covering the procedure.