Figure 1. The same breast imaged on (A) an analog mammography system and on (B) a full-field digital mammography system.

Figure 2. A direct radiography (DR) full-field digital mammography (FFDM) system is composed of (A) the acquisition stand, which looks similar to those used in analog systems; (B) the acquisition workstation with a display monitor, a computer, and a keyboard; and (C) the diagnostic workstation with two 5-megapixel (MP) diagnostic-grade monitors and a keypad for system navigation. The diagnostic workstation may sometimes also include a third, nondiagnostic monitor for workflow management.

Figure 3. A computed radiography (CR) full-field digital mammography (FFDM) system is composed of (A) a facilityÕs existing analog acquisition stand that uses a standard mammography cassette that has a digital imaging plate in place of film; (B) a CR reader that scans (reads) the imaging plate and makes the digital image available at the technologist console for review; and (C) the diagnostic workstation with two 5-megapixel diagnostic-grade monitors. The diagnostic workstation usually includes a third nondiagnostic monitor that is used to provide worklist and other patient information. For facilities that do not read soft copy images, an FDA-cleared film printer would be used to generate films for standard viewbox reading. (Fuji Computed Radiography for Mammography [FCRm], FUJIFILM Medical Systems USA, Inc., Stamford, CT.)

Figure 4. The individual blocks of image data are called pixels. The space between the pixels is known as pixel pitch. A matrix is a group of pixels in a square or rectangular shape. Currently available full-field digital mammography detectors have pixel sizes ranging from 25 µm to 100 µ

Figure 5. When looking at different matrices, it is clear that, given the same bit depth, more pixels provide more data. For the same lesion, (A) a larger pixel size will provide 4 pixels of data. (B) A smaller pixel will provide 6 to 8 pixels of data, whereas (C) an even smaller pixel size will provide 12 or more units of data.

Figure 6. The correct exposure is crucial for digital mammography. These are 2 images of the same breast. (A) One is overexposed and (B) the other was taken using the correct exposure.

Figure 7. Ghosting artifacts can occur when the energy from previous images is not completely removed from the imaging detector following exposure.