<> "The repository administrator has not yet configured an RDF license."^^ . <> . . "Motion Compensation in Cardiac X-Ray Computed Tomography"^^ . "Motion artifacts in cardiac CT remain an issue that can degrade image quality. In addition to\r\nartifacts originating from cardiac motion in general, irregular motion in particular may lead\r\nto unique artifacts for scanners with partial coverage of the heart. If multiple sub-volumes, or\r\nstacks, have to be reconstructed to cover the heart, irregular motion may introduce discrepancies\r\nbetween these stacks. The resulting artifacts in the finally assembled CT volume are, herein,\r\nreferred to as stack transition artifacts. A stack transition artifact removal (STAR) method\r\nbased on symmetric image registration was developed. The registration computed a smooth\r\nmotion vector field using data from the overlap of neighboring stacks. The extent of the vector\r\nfield smoothing was set automatically for individual registration tasks. Furthermore, a motion\r\ncompensation (MoCo) was developed to address the general motion artifacts in short-scan\r\ndata. This method is based on partial angle reconstructions to which a 4D motion model\r\nis applied. The latter was optimized using a cost function consisting of a penalized image\r\nentropy. The penalties refer to cardiac velocity and strain. Both methods were applied to\r\nsingle-phase reconstructions from clinical data. In addition, simulations were used with STAR.\r\nSTAR considerably improved image quality. Discontinuities were removed or clearly reduced.\r\nThe MoCo improved image quality for all artifact impaired reconstructions. In case of artifactfree\r\nimages, image quality was maintained, however, a tendency for a minor blurring in the\r\nmotion-compensated images was observed. Finally, both artifact correction methods showed a\r\ncapability to clearly improve image quality."^^ . "2021" . . . . . . . "Sergej"^^ . "Lebedev"^^ . "Sergej Lebedev"^^ . . . . . . "Motion Compensation in Cardiac X-Ray Computed Tomography (PDF)"^^ . . . "Dissertation Lebedev.pdf"^^ . . . "Motion Compensation in Cardiac X-Ray Computed Tomography (Other)"^^ . . . . . . "indexcodes.txt"^^ . . . "Motion Compensation in Cardiac X-Ray Computed Tomography (Other)"^^ . . . . . . "lightbox.jpg"^^ . . . "Motion Compensation in Cardiac X-Ray Computed Tomography (Other)"^^ . . . . . . "preview.jpg"^^ . . . "Motion Compensation in Cardiac X-Ray Computed Tomography (Other)"^^ . . . . . . "medium.jpg"^^ . . . "Motion Compensation in Cardiac X-Ray Computed Tomography (Other)"^^ . . . . . . "small.jpg"^^ . . "HTML Summary of #30242 \n\nMotion Compensation in Cardiac X-Ray Computed Tomography\n\n" . "text/html" . . . "530 Physik"@de . "530 Physics"@en . .