DESIGN CRITERIA FOR AND EVALUATION OF PHANTOMS EMPLOYED FOR MAMMOGRAPHY

Phantoms in diagnostic radiology are used to simulate the interaction of the radiation beam with the patient. The patients' anatomy varies c onsiderably, phantoms are therefore generally designed to represent on e or a few typical sizes and compositions, usually the average value o ut of some distinct population. One major purpose of the use of phanto ms is the assessment and verification of performance standards in dail y clinical practice with respect to image quality and dose. Important demands on such phantoms are easy availability, reproducibility and a design which allows evaluation of the tests to be performed in an obje ctive way. A proposal is made here for a standard phantom to be used f or dose assessment and for checking the performance of the mammographi c system: material PMMA, semicircular with a radius 100 mm and a thick ness of 40 mm. Test objects for the evaluation of spatial resolution a nd contrast in the mammogram are described. The phantoms will allow an objective test as to whether mammographic systems are in compliance w ith established criteria concerning radiation dose and image quality.