A system for dual energy microtomography of bones

Abstract Dual energy microtomography with synchrotron radiation is used to quantitatively image the calcium distribution of bones. The object diameters are typically 10 mm. The influence of scan time and radiation dose on the signal/noise ratio is discussed with regard to bones. An algorithm to estimate the signal to noise ratio (SNR) in the Ca image is given and used for computation of the optimum energies in the dual energy mode. The experimental setup consists of a double crystal monochromator, a sample stage and a line scan detector (Reticon RL1024SF) with a phosphor for X-ray conversion. Ca density tomograms of bones with a spatial resolution of 100 μm are shown. The accuracy of the method is of the order of 5% which is demonstrated by the measurement of calibrated phantoms.

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