A raw DPC (differential phase contrast) image of an object is acquired. The background phase distribution due to the non-uniformity of the grating system is acquired by the same process without an object in place, and the true DPC image of the object is acquired by subtracting the background phase distribution from the raw DPC image.

Disclosed herein is a method, comprising: for i=1, . . . , M, sending a pencil radiation beam (i) toward an image sensor, wherein the pencil radiation beam (i) is incident on an incident region (i) on the image sensor, wherein the pencil radiation beam (i) is aimed at a target region (i) on the image sensor, wherein M is a positive integer, wherein the image sensor comprises active areas spatially discontinuous from each other, and wherein the incident regions (i), i=1, . . . , M and the target regions (i), i=1, . . . , M are on the active areas; and for i=1, . . . , M, determining an offset (i) between the incident region (i) and the target region (i).

A radiographic imaging apparatus includes an imaging apparatus and a hardware processor. The imaging apparatus obtains moire fringe images for generating a reconstruction image of a subject by using a Talbot-Lau interferometer comprising a radiation source, a multiple slit, a first grating, a second grating and a radiation detector. The hardware processor performs a control to satisfy relations (i) φ≧(½)×(R.sub.S/R.sub.1)×d.sub.1>φ×0.7, (ii) 1≦φ≦10 (μm), and (iii) 0.5≦(R.sub.s/R.sub.1)≦1. φ is a particle size of a microbubble contrast agent to be used in imaging. d.sub.1 is a slit period of the first grating. R.sub.1 is a distance between the multiple slit and the first grating. R.sub.s is a distance between the multiple slit and the subject.

Systems and methods for X-ray phase-contrast imaging (PCI) are provided. A quasi-periodic phase grating can be positioned between an object being imaged and a detector. An analyzer grating can be disposed between the phase grating and the detector. Second-order approximation models for X-ray phase retrieval using paraxial Fresnel-Kirchhoff diffraction theory are also provided. An iterative method can be used to reconstruct a phase-contrast image or a dark-field image.

The invention relates to an X-ray detector arrangement (10) for X-ray phase contrast tomo-synthesis imaging, a line detector (1) for X-ray phase contrast tomo-synthesis imaging, an imaging system (24) for X-ray phase contrast tomo-synthesis imaging, a method for X-ray phase contrast tomo-synthesis imaging, and a computer program element for controlling such arrangement and a computer readable medium having stored such computer program element. The X-ray detector arrangement (10) comprises several line detectors (1). Each line detector (1) is configured to detect a Moiré pattern in at least a portion of an X-ray beam (2) impacting such line detector (1). Each line detector (1) comprises several detector lines (11), wherein a width W of each line detector (1) equals one period or an integer multiple of the period of the Moiré pattern.

Single X-ray grating differential phase contrast (DPC) X-ray imaging is provided by replacing the conventional X-ray source with a photo-emitter X-ray source array (PeXSA), and by replacing the conventional X-ray detector with a photonic-channeled X-ray detector array (PcXDA). These substitutions allow for the elimination of the G0 and G2 amplitude X-ray gratings used in conventional DPC X-ray imaging. Equivalent spatial patterns are formed optically in the PeXSA and the PcXDA. The result is DPC imaging that only has a single X-ray grating (i.e., the G1 X-ray phase grating).

Methods and systems for detecting a dissection in surface of an elongated structure in a three dimensional medical image. One system includes an electronic processor configured to receive the three dimensional medical image and determine a periphery of the elongated structure included in the three dimensional medical image. The electronic processor is also configured to generate a non-contrast image representing the periphery of the elongated structure and superimpose a contrast image associated with the three dimensional image on top of the non-contrast image to generate a superimposed image. The electronic processor is also configured to detect at least one dissection in the elongated structure using the superimposed image and output a medical report identifying the at least one dissection detected in the elongated structure.

The invention relates to an X-ray detector device (10) for detection of X-ray radiation at an inclined angle relative to the X-ray radiation, an X-ray imaging system (1), an X-ray imaging method, and a computer program element for controlling such device or system for performing such method and a computer readable medium having stored such computer program element. The X-ray detector device (10) comprises a cathode surface (11) and an anode surface (12). The cathode surface (11) and the anode surface (12) are displaced by a separation layer (13) allowing charge transport (T) between the cathode surface (11) and the anode surface (12) in response to X-ray radiation incident during operation on the cathode surface (11). The anode surface (12) is segmented into anode pixels (121) and the cathode surface (11) is segmented into cathode pixels (111). At least one of the cathode pixels (111) is assigned to at least one of the anode pixels (121) in a coupling direction (C) inclined relative to the cathode surface (11). At least one of the cathode pixels (111) is configured to be at a voltage offset relative to an adjacent cathode pixel and at least one of the anode pixels (121) is configured to be at a voltage offset relative to an adjacent anode pixel (121). The voltage offset is configured to converge the charge transport (T) in a direction parallel to the coupling direction (C).

The present invention relates to a calculation device (10) for comparing dark-field X-ray images. The calculation device in (10) is configured for receiving a first dark-field X-ray image (11) describing first dark-field X-ray signals of a patient at an expiration state and for receiving a second dark-field X-ray image (12) describing second dark-field X-ray signals of the patient at an inspiration state. The calculation device is further (10) configured for normalizing the first dark-field X-ray signals of the first dark-field X-ray tin image (11) with a lung thickness value describing the lung thickness at the expiration state and for normalizing the second dark-field X-ray signals of the second dark-field X-ray image (12) with a lung thickness value describing the lung thickness at the inspiration state. Further, the calculation device (10) is configured for comparing the normalized first dark-field X-ray signals with the normalized second dark-field X-ray signals, thereby determining a comparison result (13) and for determining whether at least one area of the patient's lung with a ventilation defect exists based on the comparison result (13).

A method for dark-field imaging includes acquiring dark-field image projections of an object with an imaging apparatus that includes an x-ray interferometer, applying a pressure wave having a predetermined frequency to the object for each acquired projection, wherein the predetermined frequency is different for each projection, and processing the acquired projections, thereby generating a 3D image of the object. In other words, the method corresponds to acoustically modulated X-ray dark field tomography. An imaging system (400) includes a scanner (401) configured for dark-field imaging, the scanner including: a source/detector pair (402/408) and a subject support (416), a pressure wave generator (420) configured to generate and transmit pressure waves having predetermined frequencies, and a console (424) that controls the scanner and the pressure wave generator to acquire at least two dark-field projection of an object with different pressure waves having different frequencies applied to the object.