Breast dose in digital mammography

• Κύριος συγγραφέας: Λεκάτου, Αριστέα
• Άλλοι συγγραφείς: Παναγιωτάκης, Γιώργος
• Μορφή: Thesis
• Γλώσσα: English
• Έκδοση: 2017
• Θέματα: Medical physics; Dosimetry; Ιατρική φυσική; Δοσιμετρία; 618.190 757 2

Breast cancer is the leading type of cancer in women, with almost 1.000.000 cases, annually. In Greece, 4.500 new cases every year are reported, while it is estimated that 1 out of 8 women worldwide will develop breast cancer some time in her life. Due to the accelerating rate of the technological evolution and the need for the phenomenon, the mammography has evolved into the most common diagnostic tool for the early detection of breast cancer. However, the patient dose must be kept as low as reasonably achievable and it is inspected by the Diagnostic Reference Levels (DRLs). The purpose of this study is to obtain patient dose data from screening mammography examinations conducted at the University Hospital of Patras, in order to establish institutional DRLs and to compare them with the corresponding national and European values. Particularly, three hundred women, 40-80 years old, participated in the study. All mammographic examinations were performed with a Hologic Selenia Dimensions digital mammography unit. The patient characteristics (age, weight, height), exposure and technical parameters (tube voltage, tube load, target/filter material, projections, compressed breast thickness (CBT), compression force), entrance surface dose (ESD) and average glandular dose (AGD) were recorded. Moreover, data analysis and study were conducted relating the dose with the other parameters and then the DRLs were estimated for CBT 55-65 mm for all projections, craniocaudal (CC) and oblique (MLO), as the 75th percentile of dose distributions. The local dose levels proved to be lower than the corresponding national and European values. The DRLs reported, could contribute in the performance evaluation of the local practice and in the effort for further optimization and radiation protection in screening mammography.