title: An improved correction method for reducing off-focal artifacts in CT imaging.
abstract: This paper presents a new method to reduce halo artifacts in Computed Tomography (CT) images, which blur the image edges and descend the image quality. Off-focal radiation is main ill factor leading to these halo artifacts. To reduce the off-focal effects, we adopt a pre-processing method to filter the sampling data directly before reconstruction, instead of post-processing method such as edge enhancing on the reconstructed images. Different from the prior pre-processing method, we also present a new and more practical method to obtain convolution kernel and a simpler formula in this paper. Results show that after calibration by the new practical method, the off-focal radiation effects were reduced efficiently, the edges were enhanced and the image quality was improved without increasing noise.
authors.affiliation: college of information science and engineering, Northeastern University, China. sunhn@neusoft.com
authors.forename: Haining
authors.initials: H
authors.lastname: Sun
authors.forename: Shaokun
authors.initials: S
authors.lastname: Qiu
authors.forename: Shanshan
authors.initials: S
authors.lastname: Lou
authors.forename: Changjun
authors.initials: C
authors.lastname: Li
authors.forename: Jinjun
authors.initials: J
authors.lastname: Liu
authors.forename: Shuangxue
authors.initials: S
authors.lastname: Li
authors.forename: Genmiao
authors.initials: G
authors.lastname: Jiang