Introduction: Mammography is a basic examination of early breast cancer detection. Like every x-ray examination mammography has also invasive effect on patients. High quality screening programme is essential for early detection of breast cancer and low mortality due to breast cancer. Part of high quality screening programme is assuring that patients receive the lowest possible dose exposures. Purpose: Purpose of research was to calculate average dose values in every projection on mobile units of DORA breast screening programme and to compare them to average glandular doses from other studies. Methods: Mobile units of breast screening programme are equipped with Siemens Inovation Mammograph. Mean glandular doses were calculated by the formula Dance et al., 2000. Research was performed on 2999 patients (11996 projections), examined in September 2010 and September 2011. Data used in calculations were collected within IMPACS RIS system (Agfa Health care, Belgium). Research took place retrospectively. Comparison between our MGD values and values from other studies was performed after the study of correspondent references. Results: The average MGD value in mobile unit 1 was 1,57 mGy and in mobile unit 2 1,83 mGy. The value of average breast thicknesses in mobile unit 1 is 56,71 mm and on mobile unit 2 57,04 mm. The differences between MGD values in September 2010 and September 2011 on mobile unit 1 were small (less than 1 percent), and on mobile unit 2 the differences were a bit higher (3 percents). Average MGD value in DORA breast screening programme was 1,74 mGy, average thickness was 57 mm. Doses in digital mammographs used in our screening programmes were 50 percent smaller then the doses on analogue mammographs used in other studies (Rosberg et al., 2000 in Kruger et al., 2001). Conclusion: MGD values of in DORA breast screening programme depend on the mamograph used in examination. Regarding the above subject, they are half smaller than the values calculated in other studies.
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