DBP重建算法插值校正CT金属伪影

DBP Reconstruction Algorithm in Interpolation Type CT Metal Artifact Reduction

提出了一种通过减少插值误差的影响来改进抑制CT金属伪影效果的方法。基于滤波反投影(FBP)重建算法,插值后的投影数据在反投影之前进行滤波,将插值误差传播到整个投影数据从而导致重建图像质量下降。采用差分反投影(DBP)重建算法的抑制金属伪影方法,因其能够沿着优选Hilbert滤波器方向在反投影之后滤波,该属性有助于减少插值误差的传播从而改善重建图像质量。数值仿真实验验证了提出方法的有效性。

This paper proposed an improved CT metal artifact reduction ( MAR) method achieved by reducing the effect of interpolation errors. The filtered back-projection ( FBP )?type MAR algorithm filters the interpolated projection before back-projection, which leads to reconstructed image quality decreasing due to interpolation errors propagated in the whole projection data. The differentiated back-projection (DBP)-type MAR algorithm has its own way by applying filtering along the preferred Hilbert filter direction after back-projection, which can reduce the effect of interpolation errors and consequently improve quality of reconstructed image. A simulation study was performed to evaluate the proposed method.