1997 Volume 6 Issue 2 Pages 167-174
In 1991 and 1995, the quality of mammograms in the institutes participating in the Kawasaki Breast Cancer Screening Program were evaluated using questionnaires and the breast-phantom image test. In 1995 mammography equipment such as phototimers, and grid and focus size, were improved compared to those in 1991. In contrast, increased numbers of high-speed automatic film processors (45 seconds), which were used in six institutes in 1995, resulted in the use of low-contrast screen/film systems, an increase in radiation dose and relatively low scores in the breast-phantom image tests. In 1995, the number of institutes that passed the breast-phantom image test increased to 8/21 (38.1%), compared to 1/21 (4.8%) in 1991, if tests were performed on the basis of their own shooting conditions. The number of institutes that passed the tests was increased to 13/21 (61.9%) in 1995, when breast-phantom image test were carried out using the screen/film systems and shooting conditions recommended by us. Before the introduction of mammography for breast screening in Japan, quality assurance systems for mammograms should be properly established.
