Fluke Biomedical 18-222 - Manual (Page 7)

1-3
• Each set has one removable detail plate (50% glandular) containing:
- Step Wedge
- Simulated tumors (100% glandular)
- Microcalcifications (CaCO
3
)
- Tabular alumina specs (AL
2
O
3
)
- Fibril (8.7 micron) plus cladding
- Line pair test target (20 LP/mm)
1.4 Clinical Usefulness
The phantom approaches the desirable features see Section 2, page 2-2. The phantom is realistically shaped and has
the tissue equivalency of an average, firm breast. Breast detail components closely mimic the radiographic properties
and shapes of normal and pathological breast structures. The shape and configuration of the phantom makes it easy
to use by both technologists and physicists. Since the phantom is both realistically shaped and tissue equivalent, it
can be reliably used to test for radiation dose as well as image quality. A recently completed field study confirms this
assumption (6). Finally, the phantom provides valuable image quality information. The subjective assessment of detail
visibility is easy to use for routine clinical assessment while densitometric analysis provides necessary accuracy for
laboratory work. Hence the phantoms may be used to assess the mammographic process as well as assuring
consistent image performance.
Table 2-3 provides a comparison of composite attenuation for various mammographic phantoms currently
commercially available. Also shown are similar calculations for breast tissue using Hammerstein's methodology (11).