BI-RADS decoded: detailed guidance on potentially confusing issues.

The American College of Radiology (ACR) Breast Imaging Reporting and Data System (BI-RADS) is the product of the initial collaboration between various committees of the ACR and several other organizations, such as the American College of American Pathologists and the American College of Surgeons. The impetus to establish a standardized method of reporting and follow-up began as early as 1985 when several of our clinical colleagues made a plea to the ACR to improve the reporting of mammograms. Reports were ambiguous and difficult to interpret, often leaving the clinician without a clear-cut management scenario. Over the years of increasing BI-RADS usage, the BI-RADS committee of the ACR received questions which, when analyzed, focused on specific areas of BI-RADS. A review of these problematic areas, with appropriate guidance, will be presented along with an introduction to the new US and MR imaging lexicons focusing on unique descriptors.