Assessment of Automated Breast Ultrasound

1. After appropriate training and certification of technologists and Mammography Quality Standards Act (MQSA) qualifications of the participating radiologists, the investigators will recruit sequentially approximately 600 women known to have a defined region of highly dense tissue or with known heterogeneously dense and/or primarily dense breast tissue (from a prior mammogram) who are scheduled to undergo routine mammography screening that includes a DBT examination. 2. Consenting women will undergo a DBT examination as part of their routine clinical exam and an ABUS examination as a part of the experiment. All examinations will be performed by certified technologists in the performance of each of the procedures in question (DBT or ABUS). 3. DBT, ABUS, and a combination of both, will be independently reviewed and interpreted (Breast Imaging, Reporting and Data System rated) by experienced and specifically trained, MQSA qualified radiologists in a cross balanced (cases by mode and by reader) study design. 4. Using the results of the interpretations in a slightly modified "LOGICAL OR" mode, namely the highest rating determines the recommendation/need for follow up, the investigators will perform imaging based diagnostic work ups as needed (i.e., resulting from the "arbitration step"). All diagnostic follow up studies, as needed, will not be a part of the study protocol, with the exception of acquiring diagnostic outcome measures from medical records. 5. The investigators will compare rates of false positives as a result of interpreting DBT vs. ABUS vs. a combination of both, including recall for additional testing, short-interval follow-up rates and biopsy rates. The sample in this preliminary study is too small to assess positive predictive values (PPVs), so the investigators will focus here on negative predictive values (NPVs). For marginal value assessment when utilizing both modalities, the investigators will also assess the type of abnormalities detected by each modality, assuming that a larger study will be required to assess cancer detection rates (by type etc.).