Akademik Veri Yönetim Sistemi
RADIATION PHYSICS AND CHEMISTRY, cilt.177, 2020 (SCI-Expanded)
Mammography technique is based on imaging of human breast using low-x ray energies. The main purpose of mammography is to detect breast cancer and prevent deaths related to it. The breast is made up mainly of two types of tissue; one is fat and the second is glandular tissues which is the most sensitive tissue to radiation. The Mean Glandular Dose (MGD) is used to monitor the dose received by the breast during breast imaging procedures that use ionizing radiation, and could be associated to the risk of radiation induced cancer. The MGD cannot be measured directly but can be determined using measurements of the Entrance Surface Air Kerma (ESAK) at the breast surface and conversion factors calculated from Monte Carlo simulations. Beryllium oxide (BeO) dosimeters, which exhibit properties such as nearly tissue-equivalence, fast annealing protocol, easy to read in Optically Stimulated Luminescence (OSL) technique and low-cost commercially availability, has been attractive for radiation dosimetry. In this work, Entrance Surface Dose (ESD), Backscatter Factor (BSF) and MGD values were determined with BeO OSL, for polymethyl methacrylate (PMMA) phantoms of different thicknesses. This study is the first attempt in the literature to determine dosimetric quantities used in mammography, such as ESD and MGD using BeO dosimeters. Similar measurements were performed with TLD-100 dosimeters and ionization chamber and all results were compared with each other. The results for MGD are in good agreement both between each other and with EUREF protocol within error limits. BeO shows a linear response as a function of ESAK for values between 1.0 and 12.0 mGy. Good reproducibility, within 5%, of BeO OSL signal was observed when exposed to mammography X-ray beams. It is concluded that BeO dosimeters could be considered as an alternative dosimeter to determine MGD in mammography.