Traditionally, radiologists took simple X-rays of suspected breast cancer patients to identify lesions and calcifications. However, this technique had limitations, usually because it was difficult to identify small abnormalities.
Breast tomosynthesis was a significant upgrade in mammography technology, arriving in the 1990s. It offered a more comprehensive view of breast tissue, letting clinicians diagnose breast abnormalities more accurately.
How Does Breast Tomosynthesis Work?
Breast tomosynthesis is an advanced form of mammography that uses a low-dose X-ray system and computer reconstructions to create three-dimensional images of the breasts. Clinicians use it in the early detection and diagnosis of breast disease, particularly in those with dense breast tissue. This advance overcomes the standard limitations of mammography, which can miss some lesions and tumors because they overlap with the surrounding tissue.
Standard mammograms require taking two X-ray images of each breast at different angles. Clinicians compress breasts between plastic paddles connected to an imaging detector. Emitters run X-rays through the tissue, with the collector collecting the outputs, a technology that dates back to the 1930s.
However, in breast tomosynthesis, the X-ray tube moves in an arc over the compressed breast, taking multiple images from different angles. Computers then synthesize two-dimensional readings of breast tissue slices into three-dimensional images. Consequently, radiologists can see more details and identify abnormalities that may be hidden or obscured in a standard mammogram.
Most clinicians use breast tomosynthesis as a screening test for women who have no signs or symptoms of breast cancer. The CDC recommends the technique for women over 40 and those at risk of developing breast cancer in the future.
However, radiologists may also use it as a diagnostic test for women with abnormal findings on a standard mammogram or clinical exam. Because the system generates 3D images from 2D breast slices or cross-sections, it emphasizes more relevant detail for diagnosis and analysis.
Advantages And Disadvantages Of Breast Tomosynthesis
Like all imaging technologies, breast tomosynthesis offers advantages and disadvantages.
- Reduced number of false positives. In traditional mammography, small abnormalities are hard to distinguish from breast tissue. Therefore, examiners may conclude healthy breasts are cancerous if they cannot differentiate between breast tissue types, leading to more patient stress. Breast tomosynthesis reduces this risk significantly by helping to visualize abnormal tissue.
- Improves breast cancer detection rates. Breast tomosynthesis also improves breast cancer detection rates, especially for small lesions and other signs of breast cancer hidden by overlapping breast tissue in conventional mammograms. This can lead to earlier diagnosis and treatment of breast cancer when it is most treatable.
- Better results for dense breasts. Breast density reflects the quantity of glandular and fibrous tissue in the breasts compared to fatty tissue. Dense breasts can make it harder to see breast cancer on conventional mammograms, but breast tomosynthesis can minimize the tissue overlap and show more details of the breast structure. Taking X-rays at different angles gives clinicians a complete picture for accurate diagnosis.
Unfortunately, breast tomosynthesis also comes with disadvantages. These include:
- High radiation dose. Breast tomosynthesis exposes patients to more radiation than conventional mammography, although it remains within safe radiation limits. The radiation dose from breast tomosynthesis is about twice as much as from standard mammograms – equivalent to the natural background radiation that a person receives in about seven weeks. Even so, some patients may worry about how the radiation dose could impact their bodies and well-being.
- Longer time to perform. Breast tomosynthesis also takes longer than conventional mammography, which may cause more discomfort for the patient. While breast compression is similar for both methods, tomosynthesis requires more image taking from different angles, around 10 seconds per view. By contrast, conventional mammography only takes around 4 seconds per view.
- More storage space and processing time. Lastly, breast tomography requires more computer resources than a traditional mammogram. This aspect of the diagnostic technique may increase the cost of computer memory and processing power to store and reconstruct images.
Who Can Benefit From Breast Tomosynthesis?
Many women can benefit from breast tomosynthesis. For instance, it may reduce the need for additional tests or biopsies for women with overt cancer by providing more detailed images of the breast tissue. Diagnosis may be significantly more straightforward for patients with dense breasts, a family or personal history of breast cancer, or previous abnormal mammograms.
Women at high risk of developing breast cancer due to genetic factors or other reasons may also benefit. More comprehensive screenings and analysis could offer them superior detection versus standard mammography, helping to catch lesions and other clinically significant signs before they develop further.
How Do Hologic Technologies Overcome Breast Tomosynthesis’s Limitations?
Hologic is a breast diagnostic equipment manufacturer committed to improving women’s health. The brand offers several advanced technologies designed to overcome some limitations associated with standard breast tomosynthesis.
Some of its technologies include:
- C-View – software that generates a synthetic 2D image from the 3D tomosynthesis data, eliminating the need for a separate 2D exposure and reducing the radiation dose by up to 40%. It also improves workflow and patient comfort by shortening the scan time and compression.
- Clarity HD – a high-resolution detector that provides sharper and clearer images with a pixel size of 70 microns compared to standard 100 or 140 microns. The technology also facilitates faster image acquisition and reconstruction, resulting in shorter scan time and lower motion artifacts.
- Intelligent 2D – an upgraded and more recent version of C-View that uses artificial intelligence (AI) algorithm that optimizes the contrast and brightness of the synthetic 2D image based on the characteristics of the breast tissue, improving the visibility of subtle lesions on Hologic Dimensions 3D devices
In summary, breast tomosynthesis, a type of 3D mammography, offers significant advantages over standard X-ray-based mammograms. However, it comes with limitations. Fortunately, Hologic 3Dimensions devices equipped with advanced technologies reduce or eliminate many of these, enhancing the patient experience substantially.
Mammo.com offers a range of the latest imaging devices from Hologic, compatible with the brand’s latest innovations. For more information, view our website or call our team.