4D computed tomography reconstruction from few-projection data via temporal nonlocal regularization.

an interesting paper. 4D computed tomography reconstruction from few-projection data via temporal nonlocal regularization. The main idea is that, for cardiac imaging, the motion of the heart is smooth. So They use the images whose corresponding heart phase is near the reconstructed one as constraint.

where J() is the non local mean operator.

Images of all the phases are reconstructed simultaneously.