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Performance tests for mammographic film-screen combinations: use of absolute techniques.

PURPOSE
A performance comparison of film-screen combination used in mammography was conducted using conventional and new techniques.


MATERIALS AND METHODS
The performance of 30 mammographic film-screen combinations was evaluated by sensitometry, and the total performance was determined using phantom measurements. Quantum detection and light emission efficiency of the screens were also measured as an alternative technique for determining screen speeds. These efficiency measurements provided quantitative results for selecting the optimum beam quality.


RESULTS
Considering the image quality scores from three observers and the radiation doses obtained from the speed measurements, eight combinations were selected as being optimal. Only three of the mammographic film screen combinations in this group were the recommendations of manufacturers.


CONCLUSION
The total performance phantom can be effectively used for the qualitative check of image and provide speed information for mammographic film-screen combinations comparable to sensitometric techniques.