An Improved Helical Cone-beam CT Image Reconstruction
This paper describes a flexible new method for accurate cone-beam reconstruction with source position on a helical orbit, which is called hybrid filter method. The inversion formula employed by this hybrid filter method is based on first applying Hilbert and ramp transforms for a combination with a simple rotation angular derivative and a direct weight in the projection space and then backprojecting the filtered data. First, about the derivatives with respect to the coordinates on the detector panel have been avoided,which results in quality improvement and reduced artifacts. Second, the new algorithm still performs a 1D shift-invariant filtering to the modified data on the detector panel and the redundancy weight to the filtered data is applied after filtering. Third, the introduction of ramp filter can further promote image resolution than Hilbert filter.
Helical cone-beam CT Hilbert filter Ramp filter
Yang Gao Jianhua Ma Wufan Chen
School of Biomedical Engineering Southern Medical University Guangzhou,510515,China
国际会议
北京
英文
1-5
2009-06-11（万方平台首次上网日期，不代表论文的发表时间）