Computer Tomography (CT) is one of the efficient imaging techniques employed in medical field for the past few decades. In CT Scanning, image quality has influenced by several factors like noise, slice thickness, minimum and maximum contrast resolution, radiation dose etc., Radiation dose is one among important and challenging issues taken to optimize the reconstruction algorithm in CT. The radiation dose is controlled by tube current*time product (mAs), pitch or table speed, slice thickness, beam energy (kVp) and number of patients. In this paper, Landweber algorithm is used to check the improvement in quality of image in low radiation dose. The projected algorithm is compared with existing iterative reconstruction algorithm in Test Phantom, Head image and Thorax image and shows better results. The proposed methods will be useful to optimize an iterative reconstruction algorithm with adequate level of quality in computer tomography.
computer tomography, fan beam tomography, image reconstruction, iterative algorithm, parallel beam tomography, radiation dose
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