One slice is great; more slices can be better.
Tomosynthesis, more commonly called 3D mammography, is a relatively new technology that helps physicians "see" breast cancers that were previously more difficult to detect.
Patricia Buchanan, MD, a radiologist with Blue Ridge Radiology at Augusta Health, has been reading 3D mammograms for about two years. "Digital mammography, what you might call 2D mammograms, is very good. If the breast tissue is not very dense, the mammogram can be relatively easy to read," explained Dr. Buchanan. "If the patient has dense breast tissue, though, it can be difficult to find a lesion because it may be covered up by normal tissue. Up to 50% of women have dense breast tissue. With 3D mammography, instead of one image added together, I get from 30 to 100 'slices' of images and I am able to look through the tissue and make a more certain diagnosis."
Amy Patterson, RT RM, who has been a mammographer for 15 years at Augusta Health, added, "For the patient, the experience of having a mammogram is not different with 3D, but the image the doctor sees is different. If you imagine a deck of cards, a digital mammogram gives an image like looking top-down at the top card. The 3D mammogram gives many images, like fanning through all the cards in the deck."
Dr. Buchanan notes that 3D is used frequently for diagnostic mammograms—which differ from an annual screening mammogram. With a diagnostic mammogram, the physician is investigating a problem the patient has reported—such as a lump, pain or discharge—or performing a 'call back' mammogram because something unusual was seen in the screening mammogram.
"Quite a number of patients are choosing 3D for a screening mammogram, as well," added Dr. Buchanan. "Certainly those patients with previous cancer, increased risk factors for breast cancer or dense breast tissue do select this option for screening." Dr. Buchanan has also seen a reduction in the need for call backs with Tomosynthesis because the thin slices may allow her to see that she is just seeing normal tissue rather than an abnormality.
For many women, their health insurance policy covers an annual screening mammogram. Not all policies, though, will cover Tomosynthesis, so there might be an additional cost to have a 3D Mammogram. Medicare does pay for 3D mammography.
"Digital mammography has benefit for all, but for some, there is additional benefit from 3D mammography. As a patient, you can discuss your decision with your healthcare professionals so you can determine if it will be a benefit for you," said Dr. Buchanan.