An image processing apparatus comprises a generating unit configured to generate, using a plurality of radiation images corresponding to mutually different radiation energies, a first material decomposition image that indicates a thickness of a first material and a second material decomposition image that indicates a thickness of a second material that differs from the first material. The generating unit generates, using the first material decomposition image and the second material decomposition image, a thickness image in which the thickness of the first material and the thickness of the second material are added together.

An image acquisition unit acquires two radiographic images based on radiation which has different energy distributions and has been transmitted through a subject including a soft part and a bone part. A subtraction unit performs weighting subtraction using a predetermined initial weighting coefficient between corresponding pixels of the two radiographic images to derive a soft part image obtained by extracting the soft part of the subject and a bone part image obtained by extracting the bone part of the subject. A weighting coefficient derivation unit derives a new weighting coefficient on the basis of a pixel value of the bone part included in the bone part image. The subtraction unit performs the weighting subtraction on the two radiographic images using the new weighting coefficient to derive a new soft part image and a new bone part image.

Systems and method for performing X-ray computed tomography (CT) that can improve spectral separation and decrease motion artifacts without increasing radiation dose are provided. The systems and method can be used with either a kVp-switching source or a single-kVp source. When used with a kVp-switching source, an absorption grating and a filter grating can be disposed between the X-ray source and the sample to be imaged. Relative motion of the filter and absorption gratings can by synchronized to the kVp switching frequency of the X-ray source. When used with a single-kVp source, a combination of absorption and filter gratings can be used and can be driven in an oscillation movement that is optimized for a single-kVp X-ray source. With a single-kVp source, the absorption grating can also be omitted and the filter grating can remain stationary.

The present invention is directed to spatial-spectral filtering for multi-material CT decomposition. The invention includes a specialized filter that spectrally shapes an x-ray beam into a number of beamlets with different spectra. The filter allows decomposition of an object/anatomy into different material categories (including different biological types: muscle, fat, etc. or exogenous contrast agents that have been introduced: e.g iodine, gadolinium, etc.). The x-ray beam is spectrally modulated across the face of the detector using a repeating pattern of filter materials. Such spatial-spectral filters allow for collection of many different spectral channels using “source-side” control. However, in contrast to other spectral techniques that provide mathematically complete projection data, spatial-spectral filtered data is sparse in each spectral channel—making traditional projection-domain or image-domain material decomposition difficult to apply. Therefore, the present invention uses model-based material decomposition, which combines reconstruction and multi-material decomposition, and permits arbitrary spectral, spatial, and angular sampling patterns.

An X-ray imaging apparatus according to an embodiment of the present disclosure includes an X-ray tube, a photon counting X-ray detector, and a filter unit. A generating unit of the X-ray tube is configured to generate X-rays. The photon counting X-ray detector is configured to count photons contained in the X-rays. The filter unit is provided between the X-ray tube and the photon counting X-ray detector. The filter unit includes a first filter and a second filter. The first filter is configured to shape a spectrum of the X-rays. The second filter is configured to generate X-ray fluorescence on the basis of X-rays related to a spectrum resulting from the shaping by the first filter.

The following relates generally to motion prediction in magnetic resonance (MR) imaging. In some embodiments, a “modular” approach is taken to motion correction. That is, individual motion sources (e.g., a patient's breathing, heartbeat, stomach contractions, peristalsis, and so forth) are accounted for individually in the motion correction. In some embodiments, to correct for a particular motion source, a reference state is created from a volume of interest (VOI), and other states are created and deformably aligned to the reference state.

Methods and systems are provided for cross calibration between two or more dual energy x-ray absorptiometry (DXA) systems. In one example, a calibration phantom is scanned along with a patient during a scanning sequence, with a first system, to obtain one or more coefficients that map pixel values retrieved from a phantom image from the phantom scan to image pixel values in the reconstructed patient image from the patient scan. The one or more coefficients may be utilized to adjust and/or compare BMD values of the patient obtained when the patient is scanned with a different system utilizing a phantom with similar composition and parameters as the calibration phantom.

Some embodiments include an x-ray system, comprising: an x-ray imager including a plurality of imaging layers; an x-ray source configured to generate an x-ray beam; and an x-ray prefilter; wherein: the x-ray prefilter is configured to adjust an energy spectrum of the x-ray beam to create or decrease a level of x-ray fluence of a local minimum between two of a plurality of local maximums.

Various systems and methods are provided for an integrated filter assembly including at least one bowtie filter and at least one beam hardening filter mounted on a carriage. In one embodiment, an imaging system may include a first carriage including at least one beam hardening filter and at least one bowtie filter, a second carriage including at least two additional bowtie filters, and a carriage driving system for moving the carriages to selectively position the at least one beam hardening filter and one of the bowtie filters in a path of an X-ray beam. The at least one beam hardening filter may overlap with at least one of the bowtie filters.

Systems and method for performing X-ray computed tomography (CT) that can improve spectral separation and decrease motion artifacts without increasing radiation dose are provided. The systems and method can be used with either a kVp-switching source or a single-kVp source. When used with a kVp-switching source, an absorption grating and a filter grating can be disposed between the X-ray source and the sample to be imaged. Relative motion of the filter and absorption gratings can by synchronized to the kVp switching frequency of the X-ray source. When used with a single-kVp source, a combination of absorption and filter gratings can be used and can be driven in an oscillation movement that is optimized for a single-kVp X-ray source. With a single-kVp source, the absorption grating can also be omitted and the filter grating can remain stationary.