TLD MEASUREMENTS OF IN-VIVO MAMMOGRAPHIC EXPOSURES AND THE CALCULATEDMEAN GLANDULAR DOSE ACROSS THE UNITED-STATES

An analysis is presented of the exposures received by TLDs placed on t he breasts of 4400 women obtaining mammograms at 170 institutions acro ss the United States. Mean glandular dose and exposure were examined a s a function of compressed breast thickness. The exposure and mean gla ndular dose were found to increase linearly with breast thickness. The mean glandular dose typically delivered by the institutions was well below the limit of 3.0 mGy for the 4.5-cm breast. However, some instit utions tend to uniformly give higher doses. In such institutions appro ximately 25% of 4.5-cm-thick breasts received a mean glandular dose ex ceeding 3.0 mGy. (C) 1996 American Association of Physicists in Medici ne.