ISSN 2466-4294 (online) | rad-journal.org Vol. 2 | Issue 1 | pp. 14 – 19 doi: 10.21175/RadJ.2017.01.004 Original research paper DEVELOPMENT OF BREAST SOFTWARE PHANTOM DEDICATED FOR RESEARCH AND EDUCATIONAL PURPOSES * Kristina Bliznakova ** Laboratory of Computer Simulations in Medicine, Technical University of Varna, Varna, Bulgaria Abstract. Physical test phantoms are valuable tools in the assessment of novel breast imaging techniques. It is important that they reproduce the breast characteristics as close as possible. This paper presents a methodology for the creation of a software breast phantom that produces a structured background in both two dimensional mammography and breast tomosynthesis. The phantom is composed of spherical objects different in size placed in a semi-cylindrical container. This software breast phantom is used to further improve the existing physical phantom in terms of use of other more appropriate materials or a structure presentation different than the use of spheres. For this purpose, a simulation platform that allows the creation of software versions of the physical phantom with parameters (sizes, shapes, materials) easily adjusted by the user, was developed. Besides the research aspects of the computational phantom, the software tool has turned out to be very useful application for the training of Medical Physics Experts. Specifically, the tool has been used in the training of the participants of module 5 “The use of physical and virtual anthropomorphic phantoms for image quality and patient dose optimization” from the EUTEMPE-RX project that is related to the qualification of Medical Physics Experts in Diagnostic and Interventional Radiology. Key words: Software breast phantom, educational and research purposes * The paper was presented at the Fourth International Conference on Radiation and Applications in Various Fields of Research (RAD 2016), Niš, Serbia, 2016. ** kristina.bliznakova@gmail.com 1. INTRODUCTION Physical test breast phantoms are valuable tools in the assessment of novel breast imaging techniques. It is important that they reproduce the breast characteristics as close as possible. Such characteristics are for instance the fractal dimension and the power law exponent β of mammographic projection images, as well as other parameters like first order, second order or higher order statistical parameters. One such example is the UPenn breast phantom which provides both software and physical realisation [1]. It is also important to reproduce the imaging characteristics in three-dimensional imaging setups. The LUCMFR group at the Department of Radiology, Catholic University of Leuven has developed a physical phantom [2] that produces a structured background in both two dimensional (2D) mammography and breast tomosynthesis. This physical breast phantom is based on the work of Gang et al. [3] who showed that equal volumes of differently sized acrylic spheres provide a fractal dimension of 3 as well as a power law exponent β equal to 3. The LUCMFR phantom consists of acrylic spheres placed in an acrylic container filled either with air or with water. This phantom has been evaluated on a Siemens mammographic system with tomosynthesis option, showing results for the power law exponent in the range of the exponents measured in patient data [2]. To improve further the existing physical phantom in terms of inclusion of breast lesions, use of other more appropriate materials or structure presentation different than the use of spheres, a computer-based simulation platform was developed that allows the creation of software versions of this phantom with parameters like sizes of container and spheres, and material characteristics, which parameters can be easily adjusted by the user. This work presents the use of this software platform to generate software phantoms, dedicated for breast imaging research as well as for educational purposes. 2. MATERIALS AND METHODS 2.1. Physical phantom description The physical phantom developed at LUCMFR is composed of two main parts: an acrylic semi-cylinder container of thickness 58 mm and diameter of 200 mm, and equal volumes of acrylic spheres of six different diameters: 15.88 mm, 12.70 mm, 9.52mm, 6.35 mm, 3.18 mm and 1.58 mm [2]. The spherical objects are placed within the semi- circular container which resembles a compressed