Noori-Asl Mahsa
Department of Physics, Faculty of Science, University of Mohaghegh Ardabili, Ardabil, Iran.
J Med Phys. 2020 Jan-Mar;45(1):44-51. doi: 10.4103/jmp.JMP_88_19. Epub 2020 Mar 13.
Monte Carlo (MC) simulation codes are used extensively for modeling the nuclear medicine imaging systems, such as single photon emission computed tomography (SPECT) and positron emission tomography (PET). By using these codes, it is possible to set different imaging parameters and do various studies in the field of nuclear medicine imaging.
The aim of this study is to investigate the effective factors in improvement of the SPECT image quality by using MC simulation.
In this study, we used the SIMIND MC simulation code and Jaszczak phantom containing six spheres with different diameters placed into a water-filled cylindrical phantom for consideration of the effects of different factors on quality of the images obtained from Tc-99m SPECT imaging system. The assessment criteria used to investigate these factors included image contrast, signal-to-noise ratio (SNR) and relative noise of the background (RNB).
The results of this study show that the right choice of the arc of rotation, the image matrix size, the number of angular views, type of the collimators, and also filters used in the image reconstruction affect the quality of SPECT images. Also, we show that use of scatter correction methods can improve the image quality.
The MC simulation is a suitable tool for investigation of different factors affecting the quality of SPECT images, essentially in the studies based on the energy spectrum, such as the evaluation of the scatter correction methods.
蒙特卡罗(MC)模拟代码被广泛用于对核医学成像系统进行建模,如单光子发射计算机断层扫描(SPECT)和正电子发射断层扫描(PET)。通过使用这些代码,可以设置不同的成像参数并在核医学成像领域开展各种研究。
本研究旨在通过MC模拟探究改善SPECT图像质量的影响因素。
在本研究中,我们使用SIMIND MC模拟代码以及贾兹扎克体模,该体模包含六个不同直径的球体,放置在一个充满水的圆柱形体模中,以考虑不同因素对从Tc-99m SPECT成像系统获得的图像质量的影响。用于研究这些因素的评估标准包括图像对比度、信噪比(SNR)和背景相对噪声(RNB)。
本研究结果表明,旋转弧、图像矩阵大小、角度视图数量、准直器类型以及图像重建中使用的滤波器的正确选择会影响SPECT图像的质量。此外,我们表明使用散射校正方法可以提高图像质量。
MC模拟是研究影响SPECT图像质量的不同因素的合适工具,尤其是在基于能谱的研究中,如散射校正方法的评估。