The Radiologic Department of Hospital Universitary Dr. Josep Trueta is provided with a Siemens Mammomat Novation digital mammographic unit. This mammograph stores the images in a computerized way in the hospital PACS system, thus resulting in a big digital mammographic database. The database is stored in cases, where each case is composed by the two views of the same mammograms ( cases) or the complete case ( cases), consisting on both MLO and CC views of both patient' breasts.