In Vivo Micro Tomography

Abstract

The diagnosis of osteoporosis is challenging. Usually, the disease progresses slowly, and it is therefore difficult to detect osteoporosis early, or to document the progression of the disease and the effect of a treatment. Several researchers have observed that bone quality cannot be assessed reliably with bone density alone, and that bone microarchitecture has to be considered as well.^1-4In spite of these findings, clinical diagnosis still relies almost exclusively on the measurement of bone density. Three-dimensional computed tomography offers a way out of this dilemma. Laib, Rüegsegger, et al. showed with a three-dimensionalin vivoCT scanner that bone structure provides valuable additional information on the skeleton.^5,6In recent years, microtomography became an increasingly popular method to image complex structures with features in the micrometer range. A microtomographic system typically assesses a sample in 3D at high spatial resolution, and thus allows unobstructed visual access to the sample’s inner structure. Regardless of whetherin vivoorin vitromeasurements are to be performed, high spatial resolution is the prime factor guiding today’s CT scanner developments. Dose and scanning speed become important issues forin vivomeasurements. Since patient or subject movement have an adverse effect on image quality, the scanning speed ofin vivoCT systems has to be as short as possible.