Optimization and evaluation of digital mammography systems.
In mammography it is essential that objects with very small contrast and diameter can be distinguished. Therefore the quality of the technical aspects of the mammography equipment should be monitored at regular time-intervals. The CDMAM 3.4 phantom is specially developed to facilitate this task in analog and digital mammography systems, i.e. detecting very low contrast and detecting very small details. The CDMAM is considered to be the world gold standard and is described in the European Protocol for quality assurance in Digital Mammography.
Measurements
To make an X-ray image, the CDMAM phantom (in combination with one or more attenuation plates) should be positioned on the bucky with the smallest disc diameters at the thorax side. Four attenuation plates with a thickness accuracy of ±1% to minimize the difference in attenuation are part of the standard delivery of the CDMAM 4.0 phantom. The images can be analyzed in CDMAM 4.0 Analyzer software to determine the Contrast-Detail curve and used for evaluation of the image quality.
Applications
- Quality assurance in mammography according to the 4th edition with supplements of the European Guidelines for Quality Assurance in Breast Cancer Screening and Diagnosis (3)
- For full-field digital units
- For automatic readout (human readout is possible)
- Determination if mammographic images are indicating objects with very low contrast and very small diameter
- Monitors the image information content with the Contrast-Detail curve and the spatial resolution
- Determination of the optimum exposure technique, e.g., by variation of tube potential
- Comparison of image quality at various object thicknesses by variation of the amount of PMMA
- Determination of the optimum background density
- Comparison of different mammography systems
- Study small (0.08 mm) and large (1-2 mm) diameter contrasts
