Validation of a method to simulate the acquisition of mammographic images with different techniques

Abstract

A previously developed image modification method used to simulate mammographic images as if acquired with different detectors and at different dose levels was extended to account for changes in the acquisition technique factors. The method was validated using two 3D printed realistic breast phantoms denoted ‘Anna’ and ‘Barbara’ of thickness 34 mm and 50 mm, respectively. A complete imaging system characterization of a commercial digital mammography system was performed. Using this system, three images from each phantom were acquired with Mo/Mo 26 kV and Rh/Rh 29 kV spectra, respectively, at two dose levels each, denoted the original images. To validate this method, additional images at a lower dose and at lower and higher tube voltages, denoted the target images, were also acquired. The original images were modified to simulate the target images, resulting in the simulated images. The signal in the original images was changed taking into account the target images conditions. Additional noise was also added to match that in the target images. The power spectra of the target and simulated images for each acquisition factor were found to match to within an average difference of 4% and 5% for the ‘Anna’ and ‘Barbara’ phantoms, respectively. Also, average structural similarity indices of 0.999 and 0.975 respectively, were obtained, meaning that all images are very similar. The method was found to accurately reflect acquisition with different techniques, as tested with 3D printed breast phantoms of different thicknesses, making it possible to use this method for future image quality evaluation studies.