RESEARCH ARTICLE Automated Bone Volume and Thickness Measurements in Small Animal Whole-Body MicroCT Data

Purpose: Quantification of osteolysis is crucial for monitoring treatment effects in preclinical research and should be based on MicroCT data rather than conventional 2D radiographs to obtain optimal accuracy. However, data assessment is greatly complicated in the case of 3D data. This paper presents an automated method to follow osteolytic lesions quantitatively and visually over time in whole-body MicroCT data of mice. Procedures: This novel approach is based on a previously published approach to coarsely locate user-defined structures of interest in the data and present them in a standardized manner (Baiker et al., Med Image Anal 14:723–737, 2010; Kok et al., IEEE Trand Vis Comput Graph 16:1396–1404, 2010). Here, we extend this framework by presenting a highly accurate way to automatically measure the volumes of individual bones and demonstrate the technique by following the effect of osteolysis in the tibia of a mouse over time. Besides presenting quantitative results, we also give a visualization of the measured volume to be able to investigate the performance of the method qualitatively. In addition, we describe an approach to measure and visualize cortical bone thickness, which allows assessing local effects of osteolysi