Advancing in the physical fabrication of anthropomorphic breast phantoms

This study presents a new physical anthropomorphic breast phantom, which was developed through a comprehensive experimental investigation, aiming at exploring optimal 3D printing materials.

Experimentally we studied the radiological properties of twenty-two 3D printing materials, used with Fused Filament Fabrication (FFF) technology. We precisely determined the Hounsfield Units (HU) of these materials within the range of incident X-ray spectra 80 kV to 120 kV. The Computed Tomography (CT) numbers for each material were analyzed, and sets of filaments were identified as potential representatives of breast tissues. The identified materials were employed in a computational anthropomorphic phantom used in simulation CT studies to initially evaluate the anatomical and radiological realism of this new phantom. This computational phantom is based on patient Magnetic Resonance Imaging (MRI) data. The optimal pair of filaments representing gland and adipose tissue is then used to manufacture the physical phantom. In this study, an FFF dual extrusion 3D printer is employed. The evaluation is conducted at a clinical CT unit, encompassing a comparison of various features with the original breast images.

Two sets of filaments were chosen to represent the breast tissues: TPC-F and ASA-A, as well as HIPS-E and ABS-C. These sets were used in a preliminary simulation study to assess the realism of the replicated breast tissues. The simulation results indicated that HIPS-E and TPC-F exhibited the most accurate representation of essential breast tissue features. The computational anthropomorphic model, featuring segmented breast adipose and glandular tissues, was successfully manufactured using HIPS-E and TPC-F. Currently, an ongoing assessment at a clinical CT unit is in progress.

The proposed physical phantom, upon successful demonstration to replicate radiological properties across a wide range of X-ray photon energies, will become a main tool in assessing and optimizing novel technologies in the field of breast imaging.