Detection values processing apparatus

摘要

The invention relates to a detection values processing apparatus. Energy-dependent detection values are provided, which are indicative of polychromatic radiation (4) after having traversed an examination zone (5). The radiation is filtered by a filter (15) which comprises K-edge filter material. A component decomposition technique is applied to the detection values for determining K-edge attenuation values being first component attenuation values, which are indicative of an attenuation caused by the K-edge filter material, and additional component attenuation values, which are indicative of an attenuation caused by additional components of the examination zone, wherein an image of the examination zone is reconstructed from the additional component attenuation values. An image can therefore be reconstructed, which is not adversely affected by the filter, because the K-edge attenuation values are not used for reconstructing the image. This can improve the quality of the reconstructed image.

主权项

1. A detection values processing apparatus, the detection values processing apparatus comprising: a computer comprising: one or more processors and a memory communicatively coupled to the one or more processors and the memory storing instructions comprising:
a detection values providing unit configured to provide energy-dependent detection values, which are generated by a detector indicative of polychromatic radiation emitted by a radiation source, filtered by a filter which comprises K-edge filter material having a K-edge within the energy range of the polychromatic radiation, having traversed an examination zone, and detected by the detector; a component decomposition unit configured to apply a component decomposition technique to the energy-dependent detection values which determine K-edge attenuation values, and the determined K-edge attenuation values include first component attenuation values indicative of an attenuation caused by the K-edge filter material, and additional component attenuation values indicative of an attenuation caused by additional components of the examination zone; a reconstruction unit configured to reconstruct an image of the examination zone from the additional component attenuation values; wherein the additional component attenuation values include second component attenuation values indicative of an attenuation caused by photoelectric effect, and third component attenuation values indicative of an attenuation caused by Compton effect; and wherein the component decomposition unit corrects the photoelectric effect component values by subtracting from the second component attenuation values, a product of the corresponding K-edge attenuation values of the K-edge filter material and a ratio of second component attenuation values of the filter and the K-edge attenuation values of the K-edge filter material, and corrects the Compton effect component values by subtracting from the third component attenuation values, a product of the corresponding K-edge attenuation values of the K-edge filter material and a ratio of the third component attenuation values of the filter and the K-edge attenuation values of the K-edge filter material.