Characterisation of x-ray attenuation and imaging properties of 3D printable materials: Update 2025

Abstract

Phantoms are an important tool in diagnostic imaging and are used for tasks such as quality control, quality assurance and calibration of imaging systems. Advances in additive manufacturing have made 3D printing a commonly used method for the production of phantoms. To create anthropomorphic phantoms, it is necessary not only to accurately reproduce the anatomical structures, but also the X-ray attenuation properties and their energy dependence of the tissue to be imitated. In this thesis, 49 3D printing materials, including 22 FDM and 27 SLA materials, were examined regarding their X-ray attenuation properties at different energies. As in the previous study by Ma et al. (2021), cylinder samples were printed from the respective materials using the corresponding 3D printing technology, with the optimal printing parameters for each material being determined in advance. For the FDM materials, this meant optimising the printing parameters so that samples could be printed with maximum infill factor and thus with the highest possible density to accurately determine attenuation properties. The printed samples were then scanned with a micro CT (at 35, 50 and 70 kVp) and a CT (at 70, 80, 100, 120 and 140 kVp) at different energies, and their Hounsfield units were determined. In contrast to the previous study, the scans were performed with printed phantoms made of PLA rather than with a water-filled phantom in order to prevent possible water absorption by the samples. The results of this study can be used to design and produce phantoms. As this study was conducted as an extension of the previous study, there is now an even wider selection of 3D printing materials available, enabling the production of phantoms across a broader X-ray attenuation range.