MONOCHROMATIC MICROTOMOGRAPHIC IMAGING OF OSTEOPOROTIC BONE

A monochromatic beam obtained from laboratory based instrumentation ha s been used for the first time to carry out a microtomographic x-ray s can of a small segment of osteoporotic bone. The resulting tomograph p rovides an accurate map of the x-ray linear attenuation coefficient at the characteristic energy for Cu K-alpha x-rays. The bone segment was imaged in a variety of ways which are common to microtomography in or der to compare the efficacy of different experimental configurations. A Si crystal monochromator was placed before the x-ray detector in ord er to reject radiation scattered by the sample. In addition, polychrom atic scans were compared with monochromatic scans. The effects of mult iple scatter can be seen upon comparison of scans with and without the second monochromator. The results indicate that beam-hardening and x- ray scattering can significantly alter an image, thereby distorting th e interpretation of what is physically present in the specimen. An acc urate, monochromatic tomographic scanning facility is being developed in an attempt to map meaningful physical constants for various materia ls.