Performance evaluation of a pinhole SPECT system for myocardial perfusion imaging of mice.
Performance evaluation of a pinhole SPECT system for myocardial perfusion imaging of mice.
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DOI：
10.1118/1.1521939
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发表时间：
2002-12
期刊：
影响因子：
3.8
通讯作者：
Max C. Wu;B. Hasegawa;M. Dae
中科院分区：
文献类型：
--
作者：
Max C. Wu;B. Hasegawa;M. Dae
越来越多地使用转基因小鼠作为人类生理学和疾病的模型，促使专用的体内成像系统的发展，解剖和功能表征的小鼠作为辅助或替代建立离体技术。我们已经开发了一个针孔单光子发射计算机断层扫描（SPECT）系统的高分辨率成像的小鼠与心血管成像作为主要应用。在这项工作中，我们通过幻影研究系统性能的特点。空间分辨率和灵敏度分别从线源和点源的图像测量，并报告了一系列的对象到针孔的距离和针孔直径。使用均匀圆柱体模、Defrise体模和网格体模的断层图像来表征图像均匀性和空间线性。均匀体模图像不包含任何环形或重建伪影，但Defrise体模图像中轴向模糊明显。网格体模图像表现出良好的空间线性。设计并构建了一种模拟小鼠左心室灌注的新型体模，其具有不同尺寸的灌注缺陷，以评估用于小鼠心肌灌注成像的系统性能。从针孔SPECT图像测量缺损体积，并将其与根据几何公式计算的实际缺损体积相关联。线性回归分析产生r = 0.995（p < 0.001）的相关系数，证明了使用针孔SPECT测量小鼠中的灌注缺损尺寸的可行性。我们已经进行了幻影研究，以表征针孔SPECT系统的空间分辨率，灵敏度，图像均匀性和空间线性。灌注缺损大小的测量是一个有价值的表型评估，将是有用的假设检验心血管疾病的小鼠模型。
The increasing use of transgenic mice as models of human physiology and disease has motivated the development of dedicated in vivo imaging systems for anatomic and functional characterization of mice as an adjunct to or a replacement for established ex vivo techniques. We have developed a pinhole single photon emission computed tomography (SPECT) system for high resolution imaging of mice with cardiovascular imaging as the primary application. In this work, we characterize the system performance through phantom studies. The spatial resolution and sensitivity were measured from images of a line source and point source, respectively, and were reported for a range of object-to-pinhole distances and pinhole diameters. Tomographic images of a uniform cylindrical phantom, Defrise phantom, and grid phantom were used to characterize the image uniformity and spatial linearity. The uniform phantom image did not contain any ring or reconstruction artifacts, but blurring in the axial direction was evident in the Defrise phantom images. The grid phantom images demonstrated excellent spatial linearity. A novel phantom modeling perfusion of the left ventricle of a mouse was designed and built with perfusion defects of varying sizes to evaluate the system performance for myocardial perfusion imaging of mice. The defect volumes were measured from the pinhole SPECT images and correlated to the actual defect volumes calculated according to geometric formulas. Linear regression analysis produced a correlation coefficient of r = 0.995 (p < 0.001), demonstrating the feasibility for measurement of perfusion defect size in mice using pinhole SPECT. We have performed phantom studies to characterize the spatial resolution, sensitivity, image uniformity, and spatial linearity of the pinhole SPECT system. Measurement of the perfusion defect size is a valuable phenotypic assessment and will be useful for hypothesis testing in murine models of cardiovascular disease.