Digital breast tomosynthesis, also known as 3-D mammography, was approved by the FDA in 2011 and is one of the most important technologic advances in the history of breast imaging. This latest advance allows the radiologist to look through the breast in one millimeter slices. This helps to uncover cancers that might be hiding within overlapping normal breast tissue. Although 3-D imaging of the breast is most helpful in patients with denser breast tissue, it has also been proven to be of benefit to patients with all types of breast tissue.
Breast tomosynthesis/3-D imaging usually involves acquiring both standard 2-D images and 3-D views for each patient. The 2-D images allow for comparison with prior mammographic studies and better assessment of calcifications. The 3-D images help to visualize masses and areas of tissue distortion that might be obscured by overlapping breast tissue, and enables the radiologist to evaluate the edges of masses to help determine which masses are more suspicious for cancer.
With the addition of 3-D mammography there is no difference in the amount of breast compression or in the number of times the breast is compressed. The patient is simply compressed for approximately four seconds longer per image.
Total radiation exposure is still very low and is well within federal guidelines. Some breast imaging programs are creating 2-D images from the 3-D images. These synthesized 2-D images were approved by the FDA in 2013 and help to reduce the patient's overall radiation dose and decrease time with the breast in compression.
Breast tomosynthesis/3-D imaging has important benefits for patients. It increases the accuracy of radiologists' interpretation of mammograms, resulting in more cancers found with fewer patients recalled from screening. Multiple studies have confirmed a significant 30 percent to 50 percent increase in the cancer detection rate. This facilitates our ultimate goal of early breast cancer detection.
Studies have also demonstrated a 20 percent to 40 percent decrease in the number of women who need additional imaging following screening mammography. This helps to reduce patient anxiety. Furthermore, more women who are recalled from screening are able to go directly to ultrasound imaging without requiring additional mammographic views. This helps decrease the patient's overall radiation exposure and discomfort.
In summary, digital breast tomosynthesis or 3-D mammography is helping to advance the fight against breast cancer.