Abstract: A processing component (122) processes images based on an iterative reconstruction algorithm with regularization and/or de-noising algorithm. The processing component includes a set point determiner (224) that determines a quality set point (216) between predetermined lower and upper quality bounds (226) based on a quality variable (228) indicative of an image quality of interest. The processing component further includes a comparator (214) that compares, each processing iteration, a quality metric of a current generated image with the quality set point and generates a difference value indicative of a difference between the quality metric and the quality set point.

Abstract: The present invention relates to C-arm X-ray imaging. In order to provide C-arm CT image acquisition with an enlarged gating window, a C-arm structure (12) for X-ray imaging is provided, comprising a C-arm (32), a movable C-arm support (34), an X-ray source (36), and an X-ray detector (38). The C-arm comprises a first end (40) and a second end (42), wherein the X-ray source is mounted to the first end and the detector is mounted to the second end. The C-arm is mounted to the C-arm support such that the X-ray source and the detector are movable around an object (44) of interest on respective trajectories (46). The X-ray source comprises at least a first focal spot (48) and a second focal spot (50) spaced apart from each other with a focal spot distance (52) in an off-set direction (54), which offset direction is aligned with the trajectory.

Abstract: An apparatus for and a method of correcting an image for an image artifact. An initial image is corrected by an image artifact corrector (190). The so corrected sample correction image is compared with the initial image to obtain information on the corrective action. The corrective action is then adaptively reapplied by a controller (140) to obtain an improved corrected image thereby ensuring previously present artifacts are removed and creation of new artifacts are avoided.

Abstract: The noise of a detection value acquired by an imaging system (30) can depend on the contributions of different components within a region of interest to be imaged, which has been traversed by radiation (4) causing the respective acquired detection value. This dependence is considered while iteratively reconstructing an image of the region of interest, wherein first component attenuation values, which correspond to elements of a first component within the region of interest, and second component attenuation values, which correspond to elements of a first component within the region of interest, are determined, wherein noise values are determined from the first component attenuation values and the second component attenuation values and wherein the noise values are used for updating the image. This consideration of the dependence of the noise of an acquired detection value on the different components improves the quality of the iteratively reconstructed image.

Abstract: A method includes reconstructing measured projection data using an iterative statistical reconstruction algorithm that reduces image artifact caused by differences in variances in projections of the measured projection data used to update a voxel of the image for one or more voxels of the image. A reconstructor includes a processor that reconstructs measured projection data using an iterative statistical reconstruction algorithm that reduces or mitigates image artifact caused by differences in variances in projections used to update a voxel of the image for one or more voxels of the image. A computer readable storage medium encoded with computer executable instructions, which, when executed by a processor of a computer, cause the processor to: reduce image artifact caused by differences in variances in projections used to update a voxel of an image for one or more voxels of the image using an iterative statistical reconstruction algorithm.

Abstract: The invention relates to a forward projection apparatus for performing a forward projection through an image (22), wherein at least one of a number of rays (20, 21) for performing the forward projection, a ray spacing between the rays and a kernel width of an interpolation kernel for calculating interpolated values located on the rays is varied depending on the ray width relative to an effective image element spacing between image elements (24) of the image. This allows reducing artifacts in simulated projection data and, thus, in an image, which is iteratively reconstructed by using the simulated projection data. For example, if the number of provided rays and/or the ray spacing between the provided rays is varied, aliasing artifacts can be reduced. Moreover, if the ray spacing between the provided rays and/or the kernel width of the interpolation kernel is varied, artifacts caused by varying effective kernel widths may be reduced.

Abstract: A method for assessing measurement quality in acquisition of an image of the interior of a medium (1) is provided. The method comprises the steps: subsequently irradiating the medium (1) with light from a plurality of different source positions (s) and, for each source position, detecting light emanating from the medium in a plurality of different detection positions (d) for acquisition of an image of the interior of the medium (1). The method further comprises the step: providing information about whether the measurement quality is deteriorated by exploiting signal symmetry under reversal of the light path.