Impact of tissue kinetic heterogeneity on PET quantification: case study with the L-[1-11C]leucine PET method for cerebral protein synthesis rates.
Impact of tissue kinetic heterogeneity on PET quantification: case study with the L-[1-11C]leucine PET method for cerebral protein synthesis rates.
复制标题
组织动力学异质性对 PET 定量的影响：使用 L-[1-11C]亮氨酸 PET 方法测定脑蛋白合成率的案例研究。
DOI：
10.1038/s41598-017-18890-x
复制
发表时间：
2018
影响因子：
4.6
通讯作者：
Schmidt,KathleenC
中科院分区：
文献类型：
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作者：
Veronese,Mattia;Bertoldo,Alessandra;Tomasi,Giampaolo;Smith,CarolynBeebe;Schmidt,KathleenC
正电子发射计算机断层扫描的功能量化通常基于假设组织区域在动力学上是均匀的建模。即使在足够小到接近均质性的区域，由于PET扫描仪的分辨率限制而产生的溢出效应也可能将不均匀动力学引入测量数据。在这里，我们考虑在可访问的最小体积，单个图像体素处的动力学异质性的影响。我们使用L-[1-11C]亮氨酸正电子发射计算机断层扫描技术，比较了考虑动力学异质性的DO(频谱分析迭代滤波法，SAIF)和DO(基函数法，BFM)两种方法估计的体素方向的大脑蛋白质合成率(RCP)。在具有良好计数统计的高分辨率PET数据中，BFM产生的RCP估计值与SAIF相当，但计算成本更低；因此可以应用更简单、成本更低的方法。由于计数统计数据较差(注射放射性示踪剂剂量较低)，BFM估计更有偏差。在模拟低分辨率PET的平滑数据中，BFM得出的RCP估计比SAIF高9-14%，这与将同质组织模型应用于运动不同的数据是一致的。因此，对于分辨率较低的数据，有必要在分析中考虑动力学异质性。动力学异质性可能会以不同方式影响其他示踪剂和扫描方案的分析；应根据具体情况进行评估。
Functional quantification with PET is generally based on modeling that assumes tissue regions are kinetically homogeneous. Even in regions sufficiently small to approach homogeneity, spillover due to resolution limitations of PET scanners may introduce heterogeneous kinetics into measured data. Herein we consider effects of kinetic heterogeneity at the smallest volume accessible, the single image voxel. We used L-[1-11 C] leucine PET and compared rates of cerebral protein synthesis (rCPS) estimated voxelwise with methods that do (Spectral Analysis Iterative Filter, SAIF) and do not (Basis Function Method, BFM) allow for kinetic heterogeneity. In high resolution PET data with good counting statistics BFM produced estimates of rCPS comparable to SAIF, but at lower computational cost; thus the simpler, less costly method can be applied. With poorer counting statistics (lower injected radiotracer doses), BFM estimates were more biased. In data smoothed to simulate lower resolution PET, BFM produced estimates of rCPS 9–14% higher than SAIF, overestimation consistent with applying a homogeneous tissue model to kinetically heterogeneous data. Hence with lower resolution data it is necessary to account for kinetic heterogeneity in the analysis. Kinetic heterogeneity may impact analyses of other tracers and scanning protocols differently; assessments should be made on a case by case basis.