公开(公告)号：US20030190065A1

公开(公告)日：2003-10-09

申请号：US10397597

申请日：2003-03-26

申请人： CTI PET Systems, Inc.

发明人： James J. Hamill ,  Christian J. Michel

IPC分类号： G01T005/00

CPC分类号： G01T1/2985

摘要： A method for performing accurate iterative reconstruction of image data sets based on Approximate Discrete Radon Transformation (ADRT). ADRT and its inverse are implemented to provide exactly matched forward and backward projectors suitable for the Maximum-Likelihood Expectation-Maximization (ML-EM) reconstruction in PET. A 2D EM reconstruction algorithm is accomplished by initializing an estimation image. A back projection of the projection weights is then formed. A loop is begun with a controlled number of iterations. The estimated image is then forward projected using linogram coordinates. A correction ratio linogram is formed and correction factors are back projected. A normalization factor is then applied. This 2D EM method is extendable into 3D reconstructions using 3D PET lines of response. Forward projection is performed on planes extracted from the image voxels. Back projection is also performed in 2D planes, which are subsequently added into the 3D array with the correct orientations.

摘要翻译： 一种基于近似离散氡变换（ADRT）对图像数据集执行精确迭代重建的方法。 实现了ADRT及其逆向提供精确匹配的向前和向后投影机，适用于PET中的最大似然预期最大化（ML-EM）重建。 通过初始化估计图像来实现2D EM重建算法。 然后形成投影重物的背投。 一个循环以受控数量的迭代开始。 然后使用线绘图坐标向前投影估计的图像。 形成校正比例线性图，并且校正因子被反映出来。 然后应用归一化因子。 这种2D EM方法可以使用3D PET线的响应扩展到3D重建中。 在从图像体素提取的平面上进行前向投影。 背投影也在2D平面中进行，随后将其以正确的方向添加到3D阵列中。