3D analytic cone-beam reconstruction for multiaxial CT acquisitions.
3D analytic cone-beam reconstruction for multiaxial CT acquisitions.
复制标题
用于多轴 CT 采集的 3D 分析锥束重建。
DOI：
10.1155/2009/538389
复制
发表时间：
2009
影响因子：
7.6
通讯作者：
Pack,Jed
中科院分区：
文献类型：
--
作者：
Yin,Zhye;DeMan,Bruno;Pack,Jed
A conventional 3rd generation Computed Tomography (CT) system with a single circular source trajectory is limited in terms of longitudinal scan coverage since extending the scan coverage beyond 40 mm results in significant cone‐beam artifacts. A multiaxial CT acquisition is achieved by combining multiple sequential 3rd generation axial scans or by performing a single axial multisource CT scan with multiple longitudinally offset sources. Data from multiple axial scans or multiple sources provide complementary information. For full‐scan acquisitions, we present a window‐based 3D analytic cone‐beam reconstruction algorithm by tessellating data from neighboring axial datasets. We also show that multi‐axial CT acquisition can extend the axial scan coverage while minimizing cone‐beam artifacts. For half‐scan acquisitions, one cannot take advantage of conjugate rays. We propose a cone‐angle dependent weighting approach to combine multi‐axial half‐scan data. We compute the relative contribution from each axial dataset to each voxel based on the X‐ray beam collimation, the respective cone‐angles, and the spacing between the axial scans. We present numerical experiments to demonstrate that the proposed techniques successfully reduce cone‐beam artifacts at very large volumetric coverage.
