摘要:
The long scan time in PET imaging may lead to a significant loss of resolution, due to patient or organ motion. According to the present invention, the distortion or motion may be compensated by performing a forward-projection, and/or back-projection of the intermediate image on the basis of a motion field describing a motion and/or distortion of the object of interest.
摘要:
The invention relates to a method and a device for the iterative reconstruction of cross-sectional images of the heart (7) of a patient based on projections (P1, . . . P5) from different directions which are for example generated with a helical cone-beam CT scanner. A cardiac weight function (f) quantifies how near the projections (P1, . . . ) are to a given observation phase (To) of the heart cycle based on simultaneously recorded electrocardiographic signals (ECG). The whole set of projections (P1, . . . ) is divided into subsets (S1, . . . ) which each contain only projections corresponding to a similar cardiac weight (f), and an iterative reconstruction algorithm like ART uses in one update or iteration step all projections of such a subset (S1, . . . ) simultaneously.
摘要:
A method, system, and computer program product for storing result data from an external device. The method includes receiving the result data from the external device, the receiving at a system. The result data is stored into a store data buffer. The store data buffer is utilized by the system to contain store data normally generated by the system. A special store instruction is executed to store the result data into a memory on the system. The special store instruction includes a store address. The executing includes performing an address calculation of the store address based on provided instruction information, and updating a memory location at the store address with contents of the store data buffer utilizing a data path utilized by the system to store data normally generated by the system.
摘要:
The present invention relates to an imaging system for imaging a field of interest, in particular to a computed tomography system. The imaging system comprises an irradiation unit (2) which moves relative to a field of interest along a first trajectory (501) and along a second trajectory (503). While the irradiation unit (2) moves along the first trajectory (501), first detection data are acquired and, while the irradiation unit (2) moves along the second trajectory (503), second detection data are acquired. An intermediate image of the field of interest is reconstructed from at least the second detection data, and virtual detection data are determined by forward projection through the intermediate image. Finally, an image of the field of interest is reconstructed from the first detection data and the virtual detection data.
摘要:
According to an exemplary embodiment a method for movement compensation of image data of an object of interest comprises receiving projection data, receiving motion vector field data, and dividing the motion vector field data into a number of layers of motion vector field data. Furthermore, the method comprises generating motion compensated projection data by projecting at least one of the number of layered motion vector field data onto the projection data and applying a two dimensional motion compensation on the projection, and generating image data of at least one voxel by back-projecting the movement compensated projection data.
摘要:
Polyvinyl esters in the form of solid resins are obtained by free-radically initiated suspension polymerization, characterized in that the solid resin for a weight-average molecular weight Mw of
摘要:
In optical tomography, a calibration of the data may be necessary for image reconstruction. According to an exemplary embodiment of the present invention, the object of interest is used for calibration, wherein the image data is acquired during a highly oxygenated phase of the object of interest and wherein the calibration data is acquired during a low oxygenated phase of the object of interest. This may provide for an improved calibration, resulting in improved image quality.
摘要:
According to the present invention, an asymmetric acquisition system is used, where the radiation detector is arranged asymmetrically with respect to a fan beam plane of motor the scanner. Advantageously, this may allow to increase a scatter angle range for a given detector height in the direction of the rotational axis. Furthermore, this may allow for an optimal data flow for a combined volume absorption distribution reconstruction and subsequent coherent scatter CT reconstruction.
摘要:
The invention relates to a computerized tomography method, in which an examination area is scanned radiographically along a helical trajectory by a conical beam. The radiation transmitted through the examination area is measured by means of a detector unit, wherein the absorption distribution in the examination area is reconstructed exactly or at least quasi-exactly from these measured values. Reconstruction uses redundant measured values and comprises derivation of the measured values from parallel rays of different projections, integration of these values along κ-lines, weighting of these values and back-projection.