Does TIGRE have FDK reconstruction algorithm for Helical scan mode

[zezisme]

Hi
is there a FDK reconstruction algorithm for Helical scan data? I only find that it can only be reconstructed using the iterative reconstruction algorithm for Helical scan data. Thank you for your beautiful work and look forward to your reply!

[AnderBiguri]

@zezisme FDK for helical does not mathematically exist, as far as I am aware. FDK requires a circular orbit. Do you have some paper describing this, or did you assume it should work?
Asking just to know if there is more research and improvements needed for FDK, or not.

[zezisme]

@zezisme FDK for helical does not mathematically exist, as far as I am aware. FDK requires a circular orbit. Do you have some paper describing this, or did you assume it should work? Asking just to know if there is more research and improvements needed for FDK, or not.

Please forgive me for not expressing clearly. What I really want to ask you is that is there a analytical reconstruction algorithm（such as filtered backprojection）for Helical orbit. As I know, the Katsevich's algorithm is a classic cone-beam spiral CT reconstruction algorithm, Is TIGRE already supporting the analytical reconstruction algorithm for helical orbit data? Thank you again for your prompt reply！

Katsevich A. Analysis of an exact inversion algorithm for spiral cone-beam CT[J]. Physics in Medicine & Biology, 2002, 47(15): 2583.

[AnderBiguri]

Ah indeed, we don't have the Katsevich algorithm implemented. Simply lack of time, I'd be happy to help integrate it if you want to implement it.