Projection based adaptive scatter correction for CT system

In CT system, the distance between the scanned object and the detector gives a significant impact on the total scatter intensity arriving at the detector. As a result, if an object is scanned off-center, its relative distance to the detector is changing when CT system is rotating, and the detector received scatter intensity will also be changing throughout the scan. In general only after the location information is obtained from the entire 360 degree raw data, the precise scatter radiation can be predicted. This could slow down reconstruction performance a lot. In this paper, we would like to propose a purely projection based scatter correction algorithm, which can be processed independently inside each projection. The promising results of the proposed algorithm suggests the variance of scatter received at different locations could be well predicted, meanwhile the reconstruction speed could be well maintained.