Department of Biophysics, Faculty of Science, Cairo University, Cairo, Egypt.
Department of Physics, Faculty of Science, Helwan University, Cairo, Egypt.
Ann Nucl Med. 2021 Jan;35(1):47-58. doi: 10.1007/s12149-020-01534-y. Epub 2020 Oct 17.
The aim of this work was to develop a digital dynamic cardiac phantom able to mimic gated myocardial perfusion single photon emission computed tomography (SPECT) images.
A software code package was written to construct a cardiac digital phantom based on mathematical ellipsoidal model utilizing powerful numerical and mathematic libraries of python programing language. An ellipsoidal mathematical model was adopted to create the left ventricle geometrical volume including myocardial boundaries, left ventricular cavity, with incorporation of myocardial wall thickening and motion. Realistic myocardial count density from true patient studies was used to simulate statistical intensity variation during myocardial contraction. A combination of different levels of defect extent and severity were precisely modeled taking into consideration defect size variation during cardiac contraction. Wall thickening was also modeled taking into account the effect of partial volume.
It has been successful to build a python-based software code that is able to model gated myocardial perfusion SPECT images with variable left ventricular volumes and ejection fraction. The recent flexibility of python programming enabled us to manipulate the shape and control the functional parameters in addition to creating variable sized-defects, extents and severities in different locations. Furthermore, the phantom code also provides different levels of image filtration mimicking those filters used in image reconstruction and their influence on image quality. Defect extent and severity were found to impact functional parameter estimation in consistence to clinical examinations.
A python-based gated myocardial perfusion SPECT phantom has been successfully developed. The phantom proved to be reliable to assess cardiac software analysis tools in terms of perfusion and functional parameters. The software code is under further development and refinement so that more functionalities and features can be added.
本研究旨在开发一种可模拟门控心肌灌注单光子发射计算机断层扫描（SPECT）图像的数字动态心脏体模。
我们编写了一个软件代码包，该软件包基于利用 Python 编程语言强大的数值和数学库的数学椭球模型来构建心脏数字体模。采用椭球数学模型来创建包括心肌边界、左心室腔在内的左心室几何体积，并结合心肌壁增厚和运动。利用真实患者研究中的真实心肌计数密度来模拟心肌收缩期间的统计强度变化。精确模拟不同程度和严重程度的缺陷，同时考虑到心肌收缩期间缺陷大小的变化。还考虑了部分容积效应，对壁增厚进行了建模。
我们成功构建了一个基于 Python 的软件代码，该代码能够模拟具有可变左心室容积和射血分数的门控心肌灌注 SPECT 图像。Python 编程语言的最新灵活性使我们能够操纵形状并控制功能参数，以及在不同位置创建具有可变大小、程度和严重程度的缺陷。此外，该体模代码还提供了不同水平的图像滤波，模拟了图像重建中使用的滤波器及其对图像质量的影响。缺陷程度和严重程度的发现与临床检查一致，影响了功能参数的估计。
成功开发了一种基于 Python 的门控心肌灌注 SPECT 体模。该体模被证明可用于评估心脏软件分析工具的灌注和功能参数。该软件代码正在进一步开发和完善，以便添加更多的功能和特性。
