A Hierarchical Algorithm for Fast Backprojection in Helical Cone-Beam Tomography

Existing algorithms for exact helical cone beam (HCB) tomographic reconstruction involve a 3-D backprojection step, which dominates the the computational cost of the algorithm. We present a fast hierarchical 3-D backprojection algorithm, generalizing fast 2-D parallel beam and fan beam algorithms, which reduces the complexity of this step from O(N4 ) to O(N3 log N), greatly accelerating the reconstruction process.

• Type: Conference
• Year: 2004
• Where: ISBI
• Authors: Jeffrey Brokish, Yoram Bresler
• Keywords: 3-D Backprojection Algorithm, 3-D Backprojection Step, Helical Cone Beam, ISBI 2004, Medical Imaging