Dong Di, Guo Jin, Yang Yujie, Shi Liangliang, Peng Dong, Liu Zhenyu, Ripoll Jorge, Tian Jie
Annu Int Conf IEEE Eng Med Biol Soc. 2013;2013:3008-11. doi: 10.1109/EMBC.2013.6610173.
In Optical Projection Tomography (OPT), if the rotational center deviates from the central line of the image and this offset is not corrected during the reconstruction, serious blurring will happen in the final 3-dimensional (3D) result. Therefore, the high-precision rotational center location method is very important for OPT. However, existing methods are inconvenient because they need active participation during the location process. Thus, the automated and fast rotational center location method is in great demand. In preliminary work, we proposed an automated rotational center location method which consisted of a high Specimen Signal Intensity (SSI) sinogram selection and a coarse-fine search. Our method had an accuracy of about 1/4 pixel. However, further robustness analysis of our method is lacking. In this paper, we have investigated its location errors on sinograms with various SSIs and analyzed whether it was effective to use high SSI sinograms for rotational center location. Moreover, we have also discussed the relationship between location errors and the starting rotational angles. The experimental results showed that our coarse-fine method was robust under different starting angles. Meanwhile, the high SSI sinogram selection scheme improved the location precision.
在光学投影断层扫描（OPT）中，如果旋转中心偏离图像中心线且在重建过程中未对该偏移进行校正，最终的三维（3D）结果将出现严重模糊。因此，高精度旋转中心定位方法对于OPT非常重要。然而，现有方法不方便，因为它们在定位过程中需要人工积极参与。因此，对自动化快速旋转中心定位方法的需求很大。在前期工作中，我们提出了一种自动化旋转中心定位方法，该方法包括高样本信号强度（SSI）正弦图选择和粗细搜索。我们的方法精度约为1/4像素。然而，我们的方法还缺乏进一步的稳健性分析。在本文中，我们研究了其在具有不同SSI的正弦图上的定位误差，并分析了使用高SSI正弦图进行旋转中心定位是否有效。此外，我们还讨论了定位误差与起始旋转角度之间的关系。实验结果表明，我们的粗细方法在不同起始角度下具有稳健性。同时，高SSI正弦图选择方案提高了定位精度。
