Contrast Agents for Micro-Computed Tomography of Microdamage in Bone

摘要

Novel methods were investigated for detecting damaged bone tissue using contrast-enhanced micro-computed tomography (micro-CT). The presence, spatial location, and accumulation of fatigue microdamage in machined human cortical bone specimens and whole rat femora was non-destructively detected in vitro after labeling by barium sulfate precipitation, and was validated by conventional histology. Micro-CT enabled non-destructive imaging and provided 3-D spatial information, which are not possible using conventional histology. These new methods are immediately useful for in vitro scientific studies investigating the etiology of fatigue and fragility fractures in bone. Functionalized Au NPs were demonstrated to enable targeted delivery and labeled microdamage was detected using synchrotron radiation computed tomography with absorption edge subtraction. Therefore, the results of this study suggest that the ambitious goal of non-invasive (in vivo) imaging of microdamage in bone could be feasible with improvements in commercial scientific and clinical CT instruments.