International Journal of Radiation Research

en Evaluation of the relation between breast glandular absorbed dose and radiographic quality in mammography Radiation Biology Radiation Biology تحقيق بديع Original Research Background: Breast is one of the main radiological sensitive organs, hence it is important to evaluate absorbed dose to this organ especially to the glandular parts. It is the aim of this study to measure mean glandular dose and image contrast in terms of different mammographic parameters. Materials and Methods: In this study two mammography machines located at Said-al Shohada (Giotto) and Shahid Behesti (GE) hospitals were used. According to the recommendations of ACR and MQSA, breast phantoms were constructed and used for this study. For dose evaluation TLD dosimetry method was used. The TLD dosimeters were of LiF type and the reader was a Solaro TLD reader. Results: To obtain a constant contrast when increasing kVp from 22 to 24, it was necessary to reduce mAs by 12 percent. The obtained relation between these two parameters is: contrast=0.2829D-0.2427. It was also found that there is a linear relationship between contrast and image quality. The relation between these two parameters is: Image quality = 28.117 Contarst + 20.134. Increasing kVp and hence decreasing mAs results a reduction to the glandular dose, especially in patients with large breast. Increasing kVp from 28 to 30 results in reduction of dose from 6.8mGy to 5mGy. Conclusions: It was found that there has been a linear relationship between contrast and image quality. It was also found that increasing kVp necessitate to reduce mAs for a constant contrast and hence reduction of glandular dose. Mean glandular dose, radiographic contrast, radiographic quality, mammography, TLD dosimetry. 77 82 http://ijrr.com/browse.php?a_code=A-10-1-276&slc_lang=en&sid=1 M.B. Tavakoli mbtavakoli@mui.ac.ir 790031947532846001111 790031947532846001111 Yes N. Kolghi 790031947532846001112 790031947532846001112 No Z. Shahi 790031947532846001113 790031947532846001113 No Z. Shaneh 790031947532846001114 790031947532846001114 No