Positional dependence of activity determination in single photon emission computed tomography.
Positional dependence of activity determination in single photon emission computed tomography.
复制标题
单光子发射计算机断层扫描中活动测定的位置依赖性。
DOI：
10.1097/mnm.0000000000001034
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发表时间：
2019
影响因子：
1.5
通讯作者：
Price E
中科院分区：
文献类型：
--
作者：
Price E
精确的图像定量需要精确校准的探测器，是至关重要的，如果剂量测定是在分子放射治疗。当应用衰减校正（AC）和散射校正时，在单光子发射计算机断层摄影图像中已经观察到对校准位置的依赖性。这项工作调查的起源，这种依赖性在单光子发射计算机断层扫描的幻影插入填充177 Lu解决方案。在椭圆体模的中心和边缘处对113 ml球体和代表脾脏的数学模型和患者脾脏的解剖模型的插入物进行成像。对于这些插入物，对于使用AC和三重能量窗散射校正重建的图像，位置之间的校准因子差异约为10%。实验成像和蒙特卡罗模拟相结合，用于隔离可能的原因，由于成像或重建反过来。不同重建系统之间AC的不一致应用被确定为位置依赖性的起源。
Accurate image quantification requires accurate calibration of the detector and is vital if dosimetry is to be performed in molecular radiotherapy. A dependence on the position of calibration has been observed in single photon emission computed tomography images when attenuation correction (AC) and scatter correction are applied. This work investigates the origin of this dependence in single photon emission computed tomography scans of phantom inserts filled with 177 Lu solution. A 113 ml sphere and inserts representing a mathematical model of a spleen and an anatomical model of a patient spleen were imaged at the centre and edge of elliptical phantoms. For these inserts, the difference in calibration factor between the positions was around 10% for images reconstructed with AC and triple energy window scatter correction. A combination of experimental imaging and Monte Carlo simulation was used to isolate possible causes due to imaging or reconstruction in turn. Inconsistent application of AC between different reconstruction systems was identified as the origin of the positional dependence.