CT环状伪影矫正方法的改进研究

Fast Removal of CT Ring Artifacts

目的探讨能够快速有效的去除CT环形伪影的改进方法,提高CT图像经过环形伪影方法处理后复原图像的精度,提高去除环形伪影的准确度,减小环形伪影算法对图像中有用信息的干扰。方法首先将CT图形(含环形伪影)用新的变换方式进行坐标变换,随后设计一个二维滤波器对图像进行滤波矫正,并在初次修复的基础上利用一维滤波器进行对二次伪影的再修复,最后利用新的变换方式还原图像。结果改进后的方法不仅能在经过环形伪影算法中的两次坐标变换后准确的还原出原始CT图像,而且能更为准确地矫正环形伪影,有效地消弱环形伪影矫正算法对图像有用信息的干扰。结论本研究设计的方法克服了原有方法的弊端,得到了较好的结果。

Objective To explore how to remove CT ring-shaped artifact quickly and effectively,and to improve accuracy of CT reconstruction image.Methods CT graphics（including the ring-shaped artifacts）were used first in coordinate transformation with a new transformation method.A two-dimensional filter was designed to filter the image.Then,a one-dimensional filter was used to re-filter the image.Finally,a new transform method was used to restore the image.Results The two-step coordinate transformation of ring-shaped artifact algorithm resulted in accurate restored original CT image,effectively reducing its interference on useful information.Conclusion The method described in this study can overcome disadvantages of existing methods and obtain good results.