自适应滤波联合迭代重组在改善胸腹部CT伪影中的应用

Clinical Application of Adaptive Filter Combined with Iterative Reconstruction to Reduce CT Artifacts in Chest and Abdomen

目的分析自适应滤波(AF)联合迭代重组对消除双上肢不能上举的急重症患者胸腹部CT成像中条形伪影的作用。方法选取双上肢不能上举患者的影像资料,胸、腹部扫描各60例。根据原始图像采用4种重组方法,AF联合迭代重组为A组,AF重组为B组,迭代重组为C组,无AF无迭代重组为D组。图像质量主观评分采用5分法,客观评价指标包括CT值、图像噪声(SD)、信噪比(SNR)、对比噪声比(CNR),对比4种重组方法对病灶的显示效果。结果4组图像质量主观评分有统计学差异(P<0.05),A组>B组>C组>D组;客观评价中CT值无统计学差异(P>0.05);SD有统计学差异(P<0.05),A组最优;SNR值有统计学差异(P<0.05),A组最优;腹部CNR无统计学差异(P>0.05)。位于D组伪影区的病变显示在A、B、C三组中均得到不同程度改善。结论双上肢无法上举的急重症患者行胸腹部CT检查时采用AF联合迭代重组能减少条状伪影,避免重复扫描。

Objective To analyze the effect of Adaptive Filter(AF)combined with iterative reconstruction on eliminating artifacts in chest and abdomen of CT imaging.Methods Imaging data of patients who are unable to lift arms were selected,60 cases in each chest and abdomen scan.AF combined with iterative reconstruction were used in group A,AF was used in group B,iterative reconstruction was used in group C,neither AF nor iterative reconstruction were used in group D.Image quality evaluation indexes include subjective score,CT,SD,SNR,CNR,the lesion display effect were also compared.Results The score of image quality was different statistically(P<0.05),A>B>C>D.There was no statistical difference in CT value and CNR(P>0.05).SD showed statistical difference(P<0.05),and group A was the best.There were statistically significant differences in SNR values(P<0.05),and group A was the best.The lesions which located in the artifact area of group D were shown more clear in the other three groups.Conclusion The combination of AF and iterative reconstruction can reduce the artifacts and avoid repeated scanning in the chest and abdomen CT examination of patients who are unable to lift up upper limbs.