Assessment of bone mineral content from 3-D synchrotron radiation microtomography images

International audienceSynchrotron radiation /spl mu/CT (SR /spl mu/CT) may provide three-dimensional (3-D) images with spatial resolution as high as 1 /spl mu/m. The SR /spl mu/CT system developed at the European Synchrotron Radiation Facility was already used to quantify trabecular bone architecture in bone samples. Here, the authors propose for the first time to use SR /spl mu/CT to assess the mineral content in bones. This quantification is possible thanks to the monochromaticity and high photon flux of the X-ray beam extracted from synchrotron radiation. For this purpose, the authors relate the reconstructed gray levels of the images to a degree of mineralization in bone. They propose a calibration method to estimate the 3-D distribution of hydroxyapatite concentrations within the sample. This method is compared to a reference microradiography technique. Finally, the authors illustrate the possibilities of the method on 3-D images of human biopsies from osteoporotic patients before and after a treatment with bisphosphonates