摘要:
The invention relates to an imaging system for imaging an object. Projection data of the object are acquired by using a radiation source emitting primary radiation (14) from a primary focal spot (15) and unwanted secondary radiation (16) from secondary focal spots (17). A first image of the object is reconstructed from the acquired projection data, a forward projection of the secondary radiation through the first image is simulated for generating secondary projection data, and a second image is generated based on the acquired projection data and the secondary projection data. Since the secondary projection data, which can generally cause image artifacts, are determined, the reconstruction unit can consider these unwanted secondary projection data while reconstructing the second image, in order to reduce the influence of the secondary projection data on the reconstructed second image, thereby improving the image quality.
摘要:
The present invention relates to differential phase-contrast imaging of an object (108). When reconstructing image information from differential phase-contrast image data, streak- like artefacts (502) may occur. The artefacts (502) may substantially reduce legibility of reconstructed image data. Accordingly, it may be beneficial for removing or at least suppressing said artefacts (502). Thus, a method (400) for regularized phase retrieval in phase-contrast imaging is provided comprising receiving (402) differential phase-contrast image data of an object (108); generating (404) reconstructed image data of an object (108) and presenting (406) reconstructed image data of the object (108). The differential phase-contrast image and the reconstructed image data comprise a two-dimensional data structure having a first dimension and a second dimension. Generating reconstructed image data comprises integration of image data in one of the first dimension and the second dimension of the data structure. A gradient operator is determined in the other one of the first dimension and second dimension of the data structure and the data structure is employed for reconstructing image data resulting in a reduction of artefacts (500) within the reconstructed image data.
摘要:
A method includes reconstructing the projection data based on a reconstruction algorithm that compensates for both motion and tissue density changes of the moving organ across different motion phases, thereby generating motion and density compensated image data. A data compensator includes a reconstructor that reconstructs motion compensated image data based on an reconstruction algorithm that compensates for tissue density changes in a moving object.
摘要:
A microbicidal composition having at least four components. The first component is 2-25 wt % of 2,2-dibromo-3-nitrilopropionamide. The second component is 2-30 wt % water. The third component is 5-30 wt % of an aliphatic compound having 2-6 hydroxyl groups. The fourth component is 20-70 wt % of a glycol solvent.
摘要:
An achromatic phase-contrast imaging apparatus for examining an object of interest is provided which comprises two different phase gratings which have different pitches. Thus, the imaging apparatus yields phase-contrast information for two different energies. Thus, phase-information over a wider energy band can be used.
摘要:
When subjecting a patient to an MRI scan, noise generated by gradient coils in an MRI device is beautified by playing a complementary musical piece that matches the gradient coil noise in one or both of tempo and musical key. Complementary musical pieces (e.g., songs, tunes, melodies, etc.) are pre-generated for specific gradient coil sequences. Upon selection of one or more sequences to be executed during an MR scan, complementary musical pieces for the selected sequence(s) are identified and played back to a patient in the bore of the MRI device during the scan to alleviate patient stress. Tempo and/or musical key of the complementary musical pieces is adjustable (a priori or in real time) to synchronize the complementary musical piece(s) to a specific gradient sequence both rhythmically and harmonically.
摘要:
The invention relates to a method and a device for generating phase contrast X-ray images of an object (1). The device comprises an X-ray source (10) that may for example be realized by a spatially extended emitter (11) behind a grating (G0). A diffractive optical element (DOE), for example a phase grating (G1), generates an interference pattern (I) from the X-radiation that has passed the object (1), and a spectrally resolving X-ray detector (30) is used to measure this interference pattern behind the DOE. Using the information obtained for different wavelengths/energies of X-radiation, the phase shift induced by the object can be reconstructed.
摘要:
A computer tomography apparatus (100) for examination of an object of interest (107) comprising an electromagnetic radiation source (104) adapted to emit electromagnetic radiation to an object of interest (107), a detecting device (108) adapted to detect electromagnetic radiation generated by the electromagnetic radiation source (104) and passed through the object of interest (107), and a motion generation device (101, 119) adapted to move the electromagnetic radiation source (104) and the detecting device (108) with respect to the object of interest (107) along a first trajectory and along a second trajectory which differs from the first trajectory, wherein the second trajectory is selected in such a manner that electromagnetic radiation detected during performing the second trajectory provides data which complete mathematically incomplete data detected during performing the first trajectory to thereby allow a reconstruction of structural information concerning the object of interest (107).
摘要:
CT scanners have a certain scan-field-of-view defined by the fan-angle of the system. According to an exemplary embodiment of the present invention, object points outside the scan-field-of-view may be reconstructed on the basis of a system of linear equations which may be solved iteratively and with reasonable effort. Therefore, explicit regularization techniques may be applied to recover the unknown object function.
摘要:
The invention relates to a computer tomography method for the detection of a cyclically moved object in an examination zone. First, after the acquisition of the measured values, a rough image of the examination zone is reconstructed from which a region relevant for the further method is selected. For the generation of an image with reduced motion artifacts or improved temporal resolution, reconstruction windows in predefinable position are used, which are optimized in such a way that they are, on the one hand, smallest possible, on the other hand, however, sufficiently large, to be able to reconstruct all voxels of this region. Only measured values acquired within the reconstruction windows are taken into account for the reconstruction of a CT image of the region.