THE USE OF COMPUTED MICROTOMOGRAPHY TO MONITOR MORPHOLOGICAL-CHANGES IN SMALL ANIMALS

Rationale and Objectives. We investigate the methodological aspects of computerised microtomography (CmT) for monitoring the development of osteoporosis in male Sprague-Dawley rats. Methods. 120 Rats were gastr ectomized or sham operated. Femurs were prepared and tomograms with sp atial resolutions of 5-500 mm were made. Bone diameters, bone areas an d moments of inertia were determined from the tomograms. Optimal slice position and the need for spatial resolution for future in vivo appli cations were investigated. In order to minimise the absorbed dose to t he specimen, a theoretical model for determination of optimal irradiat ion conditions is developed. Results. Gastrectomy caused dramatic chan ges in the bone architecture. The main features were vaccuolisation of the bone and reduced amounts of compact bone. While the outer diamete rs of tubular bones were largely unaffected, their inner diameters wer e greatly increased following gastrectomy. Relative bone area and mome nt of inertia were greatly reduced. Optimal photon energy was 12 keV.C onclusions. It is possible to monitor gastrectomy-evoked changes in bo ne morphology at various sites in rats with computerised microtomograp hy. The changes are suggestive of osteoporosis. (C) 1998 Elsevier Scie nce Ltd. All rights reserved.