Quirin Spreiter

Technology and image results of a spectral CT system

We report the implementation and first test results of a two-channel spectral Computed Tomography (CT) prototype. We use an energy-resolving CT detector with a sandwich-like two layer set-up. Compared to dual-energy approaches with tube voltage switching, it yields a low and a high energy channel in a one shot measurement. We explain the basic set-up of the system and its calibration. The effects of spectral weighting are examined and the weighting functions w(E) of the detector channels are calculated. We present spectral image data of a water phantom, a set of calibration materials and an organic sample. Finally, we show how the data can be used for quantitative CT measurements. The system is work in progress and currently not available in the United States.