Analysis of patient dose in full field digital mammography

Abstract

Now, full field digital mammography (FFDM) is widely used in diagnosis of breast cancer. With the development of FFDM, the radiation dose delivered to the patients involved in an imaging protocol is of utmost concern. Here, we analyzed the average glandular dose (AGD) and entrance surface exposure (ESE) of 1397 patients (6008 images) who underwent mammographic examinations by FFDM in three modes with automatic optimization of parameters (AOP), namely STD for standard mode, CNT for contrast mode and DOSE for dose mode. In addition, exposure factors including kVp, tube loading (mAs), and target/filter combination were evaluated. As a result, the patient dose was sorted as CNT>STD>DOSE. The dose difference among the three AOP modes was mainly attributed to the selection of mAs. The AGD and breast compressed thickness were well correlated in STD and DOSE modes. However, the correlation between CNT-delivered AGD and breast compressed thickness was dependent on the range of the breast thickness and patient age. The findings on dose and exposure characteristics of the three AOP modes get useful message of patient dose in the acquisition of FFDM.