Effect of breast composition on patient exposure in mammography

Software for the estimation of patient exposure from mammography has been developed. Because it adopts average glandular dose, the estimation of patient exposure must take advantage of D(gN) (average glandular dose per unit entrance skin exposure). D(gN) depends on X-ray quality, compressed breast thickness, and breast composition. The software that was previously reported required information about breast composition. However, the new software that estimates breast composition uses a phantom with known breast composition to estimate average glandular dose and entrance surface dose. The authors were able to calculate average glandular dose that takes account of breast composition using this software. In addition, in a comparison with the mammogram in terms of the classification of mammary gland substance, the software showed high precision in terms of agreement. This software has sufficient utility because only the mammographic conditions are entered, and patient exposure can be easily estimated. Moreover, the half-value layer, incident exposure in air, D(gN), and breast composition can be specifically calculated.