Different irradiation configurations for typical mammographic facilities were evaluated in order to establish optimal irradiation parameters for improving X-ray image quality. The whole X-ray imaging process was suitably studied by means of Monte Carlo techniques. Relevant parameters were introduced to the program in order to evaluate their effect on image quality. Breast absorbed doses were presented as figure-of-merit with the aim of determining the optimal irradiation set-up with minimal dose delivery. It was found that anode material along with accelerating voltage significantly affected the image quality. On the other hand, micro-calcification detection was found to be strongly dependent on irradiation configurations as well as being affected by breast and micro-calcification compositions. Furthermore, by means of the adapted image processing algorithms, it was possible to quantitatively characterise the image quality as a function of different irradiation parameters. The proposed algorithms proved to be a useful, reliable and consistent tool for detail automatic detection.