改进互信息与图像金字塔相结合的二维与三维图像配准方法研究

Research on 2D-3D registration method combining improved mutual information and image pyramid

目的探讨改进互信息与图像金字塔相结合的二维-三维配准方法的价值。方法将3次B样条曲线的连续图像表示与Parzen直方图估计融合到该算法中,以胸腔作为研究对象,通过数字重建放射影像生成的正交位的模拟X线图和与其本身进行一定变换后的图像进行配准实验,观察配准精度和时间。结果经过50组对照试验得出本方法相较于传统配准方法在x、y轴向上的位移精度分别提高了53.39%、21.33%,配准时间缩短了91.93%。相较于近几年的改进算法在x、y轴向上的位移精度分别提高了17.65%、13.79%,并将配准时间进一步提高了19.64%。结论该方法可以有效提高二维-三维图像的配准精度和效率,且均符合手术过程中图像配准2 mm以内的要求。该方法的高效、准确为临床诊断和放疗自动化提供了有利的信息,同时也为肿瘤位置误差校正和医用机械臂自动摆位奠定了基础。

Objective To evaluate the value of 2D-3D registration method which combines improved mutual information and image pyramid.Methods The continuous image representation of the cubic B-spline curve and Parzen histogram estimation were fused into the algorithm.The chest was used as the research object.The reconstruction of the orthogonal X-ray image generated by the radiographic image and the image after a certain transformation with itself were used for registration experiments to study the registration accuracy and time.Results After 50 sets of controlled experiments,compared with the traditional registration method,the displacement accuracy of this method in the X and Y directions was improved by 53.39%and 21.33%,and the registration time was shortened by 91.93%.Compared with the modified algorithms in recent years,the displacement accuracy of the improved algorithm in the X and Y directions was increased by 17.65%and 13.79%.And the registration time was further increased by 19.64%.Conclusions This method can effectively improve the registration accuracy and efficiency of 2D and 3D images,and both meet the requirements of image registration within 2 mm during surgery.The high efficiency and accuracy of this method provide beneficial information for clinical diagnosis and radiotherapy automation,which also lays the foundation for tumor position error correction and automatic positioning of medical robotic arms.