Abstract：Linear interpolation (LI) is one of the basic reconstruction algorithms for multi-slice helical CT (MSCT) which searches for the upper and lower projection data sets adjacent to the reconstructed slice for interpolation. However, the searching for the data and computing the weighting function significantly reduces the reconstruction efficiency. An improved LI method was developed for a range of helical pitches with a 4-slice helical CT as an example. The algorithm defines the projection data weighting function from different detector rows, which can be used directly for interpolation to increase the reconstruction efficiency. The 3D projection data for the Shepp-Logan head phantom was simulated to verify the reconstruction capability and the applicable range of this method. The results show that this method does well for moderate and small helical pitches. The image restoration capacity is very good and the volume coverage is quite fast with good image quality. This method can be used in situations requiring fast reconstruction.
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