锥束计算机断层成像系统快速定位方法

Fast Localization Method in Cone-beam Computed Tomography

针对锥束计算机断层成像(CT)系统的定位参数测量问题,设计了一种简易的标准圆杆测具,并提出了基于该圆杆测具的快速定位测量方法。该方法在锥束CT成像区域中的4个位置分别对圆杆测具进行DR成像,得到4幅投影图像,然后利用圆杆测具在锥束CT系统中的成像特性,通过简单计算快速获取影响锥束CT切片图像质量的5个主要定位参数。实验结果表明,采用该方法可在数分钟内获取亚像素级的锥束CT系统定位参数,且由该参数重建的切片图像质量得到明显提高。

For the measurement of localization parameters in cone-beam computed tomography （ CBCT） ,a simple standard round bar measurement tool was designed,and a fast localization method based on the bar was proposed. The method should capture four projection images of the round bar tool in four positions of the CBCT imaging region,and then by using the imaging features of the tool in the CBCT system,five localization parameters influencing the image quality of the slice would be found out fastly. The ex-perimental results show that the method can obtain the localization parameters with sub-pixel precision in few minutes,and the image quality of the slice reconstructed by the parameters has been improved obviously.