How to reconstruct SPECT image from sinogram using iterative technique?

I have a raw data of sinogram in dicom file. I have to reconstruct SPECT image. I tried to reconstruct SPECT image from sinogram using radon transform (iradon) in MATLAB but this technique add artifact in the image. I would like to reconstruct by iterative technique. Could anyone help me for the code of iterative reconstruction?

Please advise me. Thank you.

[mohd akmal masud]

@Phornpailin Pairodsantikul can try this one.