BREAST DOSES FROM PATIENTS AND FROM A STANDARD PHANTOM: ANALYSIS OF DIFFERENCES

摘要

The two methods commonly used for estimating the doses in mammography are based on the use of either a standard phantom or a sample of patients. Both methods are currently applied in the Galicia Breast Screening Programme. In the range of thicknesses corresponding to the standard-szied breast (50±5 mm), the use of a standard phantom resulted in an oversestimation of the ESAK values for patients by up 13/100. The overestimation depends on the view employed and is mroe important for the CC view. Differences in compostion between the standard breast and the real breasts are the main factor that affects the results obtained with both methods. Nevertheless, if a more realistic brast composition was considered, the ESAK vlaues from sample of patients would be clsoer to dose values obtained with the standard phantom.