Alumina as a Computed Tomography Soft Material and Tissue Fiducial Marker

Background The use of 3D imaging is becoming increasingly common, so too is the use of fiducial markers to identify/track regions of interest and assess material deformation. While many different materials have been used as fiducials, they are often used in isolation, with little comparison to one another. Objective In the current study, we aim to directly compare different Computed Tomography (CT and μCT) fiducial materials, both metallic and nonmetallic. Methods μCT imaging was performed on a soft-tissue structure, in this case heart valve tissue, with markers from eight different materials attached. Additionally, we evaluated the same markers with DiceCT stained tissue in a fluid medium. Results All of the metallic markers generated significant artifacts, and were found unsuitable for soft-tissue μCT imaging, whereas alumina markers were found to perform the best, with excellent contrast and consistency. Conclusions These findings support the further use of alumina as fiducial markers for soft material and tissue studies that utilize CT and μCT imaging.