Characterization of CT Hounsfield Units Uniformity of 3D Printed Materials for Proton Therapy

Previous studies have evaluated CT Hounsfield Units (HU) uniformity for a variety of 3D printing techniques and for proton and non-proton applications; however, 3D printing technology and materials are evolving at an incredibly rapid pace and differences in methodology and results reporting between previous studies prevent straightforward comparison of 3D printer-material combinations.

The primary purpose of this work was to evaluate the HU uniformity of 3D printed samples produced by twelve 3D printer-material combinations. A secondary, inherent purpose was to develop a procedure for HU uniformity evaluation which addresses comprehensive sampling of the object volume, addresses excluding partial volume affected voxels and investigates repeatability as a function of several potential dependencies previously identified in published literature.