Breast Tomography 2-D or 3-D?
October is Breast Cancer Awareness month. You may or may not be aware of an imaging technique that is now available at some screening centers. It is called Digital Breast Tomography or DBT.
Digital breast tomography allows the radiologist to look at multiple slices through each breast. Multiple projections are taken through both breasts. Eleven exposures in total, taken during a single sweep. The images are then constructed into slices, 1 mm apart, throughout the entire breast. It is however technically still a 2-D exam.
In screening populations using the DBT system, decreased recall rates ranging from 37-42% have been reported (Rafferty al RSNA 2007 and 2008).
Dr. Greenberg from Washington Radiology Associates was quoted as stating that there has been a 20% decrease in recall rates for them and a 31% increase in cancer detection over 2-D mammograms.
Breast abnormalities are more easily seen with this technique.
This technology can be very helpful in detecting cancers in women with dense breasts. The borders are more clearly defined and cancers are better visualized. Another advantage is that an abnormality can be localized in the 3-D plane.
For those concerned about radiation dose, a 2-D mammogram/DBT combination of mammograms produces approximately 1/10 of the radiation from a CT scan of the chest according to the American College of radiology.
Each exposure is a fraction of the dose of a conventional film/screen 2D mammogram. The total dose is less than a 2 view 2-D mammographic study.
What’s important to know is that you can have one or both done and that screening for breast cancer be done in the first place. We now have the ability to detect breast cancer in the early stages and save lives.
For more information consult with your doctor and go to the National Cancer Institute website: http://www.cancer.gov/cancertopics/factsheet/detection/mammograms