Cao Xu, Li Yang, Zhan Yonghua, Chen Xueli, Kang Fei, Wang Jing, Liang Jimin
Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education and School of Life Science and Technology, Xidian University, Xi'an, Shaanxi 710071, China.
Department of Nuclear Medicine, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, China.
Biomed Res Int. 2016;2016:7948432. doi: 10.1155/2016/7948432. Epub 2016 Aug 25.
Cerenkov luminescence imaging (CLI) can provide information of medical radionuclides used in nuclear imaging based on Cerenkov radiation, which makes it possible for optical means to image clinical radionuclide labeled probes. However, the exceptionally weak Cerenkov luminescence (CL) from Cerenkov radiation is susceptible to lots of impulse noises introduced by high energy gamma rays generating from the decays of radionuclides. In this work, a temporal median filter is proposed to remove this kind of impulse noises. Unlike traditional CLI collecting a single CL image with long exposure time and smoothing it using median filter, the proposed method captures a temporal sequence of CL images with shorter exposure time and employs a temporal median filter to smooth a temporal sequence of pixels. Results of in vivo experiments demonstrated that the proposed temporal median method can effectively remove random pulse noises induced by gamma radiation and achieve a robust CLI image.
切伦科夫发光成像（CLI）能够基于切伦科夫辐射提供核成像中使用的医用放射性核素的信息，这使得光学手段对临床放射性核素标记探针进行成像成为可能。然而，切伦科夫辐射产生的切伦科夫发光（CL）极其微弱，容易受到放射性核素衰变产生的高能伽马射线引入的大量脉冲噪声的影响。在这项工作中，提出了一种时间中值滤波器来去除这类脉冲噪声。与传统的CLI不同，传统CLI通过长时间曝光采集单个CL图像并用中值滤波器进行平滑处理，而所提出的方法以较短的曝光时间捕获CL图像的时间序列，并采用时间中值滤波器对像素的时间序列进行平滑处理。体内实验结果表明，所提出的时间中值方法能够有效去除伽马辐射引起的随机脉冲噪声，并获得稳健的CLI图像。
