Moradi Hamed, Vashistha Rajat, O'Brien Kieran, Hammond Amanda, Vegh Viktor, Reutens David
Centre for Advanced Imaging, Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, Australia.
ARC Training Centre for Innovation in Biomedical Imaging Technology, The University of Queensland, Brisbane, Australia.
EJNMMI Res. 2024 Jan 2;14(1):1. doi: 10.1186/s13550-023-01061-7.
In parametric PET, kinetic parameters are extracted from dynamic PET images. It is not commonly used in clinical practice because of long scan times and the requirement for an arterial input function (AIF). To address these limitations, we designed an F-fluorodeoxyglucose (F-FDG) triple injection dynamic PET protocol for brain imaging with a standard field of view PET scanner using a 24-min imaging window and an input function modeled using measurements from a region of interest placed over the left ventricle.
To test the protocol in 6 healthy participants, we examined the quality of voxel-based maps of kinetic parameters in the brain generated using the two-tissue compartment model and compared estimated parameter values with previously published values. We also utilized data from a 36-min validation imaging window to compare (1) the modeled AIF against the input function measured in the validation window; and (2) the net influx rate ([Formula: see text]) computed using parameter estimates from the short imaging window against the net influx rate obtained using Patlak analysis in the validation window.
Compared to the AIF measured in the validation window, the input function estimated from the short imaging window achieved a mean area under the curve error of 9%. The voxel-wise Pearson's correlation between [Formula: see text] estimates from the short imaging window and the validation imaging window exceeded 0.95.
The proposed 24-min triple injection protocol enables parametric F-FDG neuroimaging with noninvasive estimation of the AIF from cardiac images using a standard field of view PET scanner.
在参数化正电子发射断层扫描（PET）中，动力学参数是从动态PET图像中提取的。由于扫描时间长以及需要动脉输入函数（AIF），它在临床实践中并不常用。为了解决这些局限性，我们设计了一种用于脑成像的F-氟脱氧葡萄糖（F-FDG）三重注射动态PET协议，使用标准视野PET扫描仪，成像窗口为24分钟，并使用放置在左心室上的感兴趣区域的测量值对输入函数进行建模。
为了在6名健康参与者中测试该协议，我们检查了使用双组织隔室模型生成的基于体素的脑动力学参数图的质量，并将估计的参数值与先前发表的值进行了比较。我们还利用了来自36分钟验证成像窗口的数据来比较：（1）建模的AIF与在验证窗口中测量的输入函数；（2）使用短成像窗口的参数估计计算的净流入率（[公式：见正文]）与使用Patlak分析在验证窗口中获得的净流入率。
与在验证窗口中测量的AIF相比，从短成像窗口估计的输入函数在曲线下面积误差的平均值为9%。短成像窗口和验证成像窗口的[公式：见正文]估计值之间的体素级Pearson相关性超过0.95。
所提出的24分钟三重注射协议能够使用标准视野PET扫描仪从心脏图像中无创估计AIF，实现参数化F-FDG神经成像。
