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Ultrasound imaging can be used to visualize the boundaries between two media with different properties, but less information is available about the medium penetrated. Therefore, conventional ultrasound devices used in routine medical imaging usually assume a constant value for the speed of sound of the structures. Thus, current research aims to develop new methods to obtain more information about the medium scanned. To support the research ultrasound phantoms with precisely known properties like speed of sound, attenuation or hardness can be used. We developed polyvinyl alcohol-based phantoms and investigated the correlation between the properties and the freeze-thaw cycles (FTC), as well as the effects of glycerol on the speed of sound. Additionally, we designed 3D printed molds for shaping the phantom and improving the FTC process. Furthermore, a construction was designed to prevent the measurement setup from being contaminated by PVA and glycerol defusing out of the phantom. The physical properties of the phantoms measured were the speed of sound, attenuation, and Shore hardness. The measurements conducted were carried out using the standards of the American Institute for Ultrasound in Medicine (AIUM) and the American Society for Testing and Materials (ASTM). There was an increase in Shore hardness and speed of sound as the number of FTCs increased. However, the differences in the speed of sound were only minimal, whereby higher differences could be achieved by the addition of glycerol. At present, no statements can be made about the attenuation. The measurements of the materials are in an early state and further improvement is needed. The manufacturing process and measurements were improved by 3D printed molds.
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