基于模型融合的有限角度CT迭代重建方法

Model-guided Iterative Reconstruction for Limited-angle CT Image

针对有限角度扫描的CT重建,提出一种基于模型融合的CT迭代重建方法。模型来源于患者的早期Dicom图像。对扫描角度有限的投影数据,用统计迭代算法进行初步重建,得到预重建图像;将预重建图像与模型进行融合,得到融合图像;然后再次投影,补全原始投影缺失的部分,根据补全的投影数据重建出中间结果,之后重复投影、融合、重建过程直到满足终止条件。仿真实验表明,该算法能完整重建整个目标,在有效保留原目标特征的同时提高了小角度投影数据重建的质量。

Aiming at the problem of limited-angle projection CT reconstruction, a model-guided iterative reconstruction for limit-angle CT image is proposed in this paper. An initial reconstructed image is firstly gained by statistical iterative algorithm from limited-angle data. The initial reconstructed image is fused with a prior-model image to acquire a fusion image. The fusion image is projected again to acquire the complementary projections, on which are the intermediate results of the reconstruction. This projection, fusion and reconstruction processes repeat until the final satisfactory image reconstructed. Simulation results have shown that the object can be reconstructed integrally by the proposed method and the quality of the final reconstructed images increase significantly, with all characteristics of the object preserved.