Simultaneous 3D visualization and quantification of murine bone and bone vasculature using micro-computed tomography and vascular replica.

Recent evidence suggests a close functional relationship between osteogenesis and angiogenesis as well as between bone remodeling and bone vascularization. Consequently, there is a need for visual inspection and quantitative analysis of the bone vasculature. We therefore adapted and implemented two different vascular corrosion casting (VCC) protocols using a polyurethane-based casting resin in mice for a true three-dimensional (3D), direct, and simultaneous measurement of bone tissue and vascular morphology by micro-computed tomography (microCT). For assessment of vascular replicas at the level of capillaries, a vascular contrast perfusion (VCP) protocol was devised using a contrast modality based on a barium sulfate suspension in conjunction with synchrotron radiation (SR) microCT. The vascular morphology quantified using the VCP protocol was compared quantitatively with the results of a previously established method, where the vascular network of cortical bone was derived indirectly from cortical porosity. The presented VCC and VCP protocols have the potential of serving as a valuable method for concomitant 3D quantitative morphometry of the bone tissue and its vasculature.