Molecular Imaging Group, Department of Radiology, Faculty of Medicine, University of Santiago de Compostela (USC), IDIS, Campus Vida, 15782, Santiago de Compostela, Spain.
Nuclear Medicine Department and Molecular Imaging Group, IDIS and University Hospital Santiago de Compostela (CHUS), Travesía da Choupana s/n, 15706, Santiago de Compostela, Spain.
Mol Imaging Biol. 2021 Jun;23(3):350-360. doi: 10.1007/s11307-020-01556-y. Epub 2020 Nov 17.
Preclinical dynamic brain PET studies remain hampered by the limitations related to the measurement of the arterial input function (AIF). In this regard, the use of an arterial-venous shunt is a promising method for the generation of real-time AIFs, but its application in longitudinal studies is still impeded by the cumbersome surgeries and high failure rates. We studied the feasibility and reproducibility of double arterial-venous shunt strategies for conducting longitudinal PET studies with real-time AIFs in rats.
We studied the feasibility of double arterial-venous shunts in rats in the right/left inguinal region and evaluated inter-animal and intra-animal AIF reproducibilities. Image-derived input function (IDIF) was also obtained for comparison. Dynamic brain FDG PET studies were conducted to estimate kinetic constants and Cerebral Metabolic Rate of Glucose (CMR) obtained from standard 2-tissue compartment (2TCM) and Patlak analysis.
We showed that longitudinal AIFs from double arterial-venous shunts can be obtained with very high success rate of the surgeries (88 %). Our results provided highly reproducible AIF measurements with low inter-animal variabilities (11 %) and intra-animal variabilities (5-10 %) that were included into the kinetic models, such that longitudinal rate constants and CMR can be efficiently estimated without bias associated to the double shunt. Our results indicated that longitudinal IDIF can be also generated without bias along time but showing higher intra-animal uncertainties.
We have demonstrated the feasibility and high reproducibility of conducting longitudinal AIF measurements and consequently accurate kinetic modeling using arterial shunt method.
临床前动态脑 PET 研究仍然受到与动脉输入函数 (AIF) 测量相关的限制。在这方面，动静脉分流的使用是生成实时 AIF 的有前途的方法，但由于手术繁琐和失败率高，其在纵向研究中的应用仍然受到阻碍。我们研究了在大鼠中使用双动静脉分流策略进行实时 AIF 纵向 PET 研究的可行性和可重复性。
我们研究了在右/左腹股沟区域进行双动静脉分流在大鼠中的可行性，并评估了动物间和动物内 AIF 的可重复性。还获得了图像衍生输入函数 (IDIF) 进行比较。进行动态脑 FDG PET 研究以估计从标准 2 组织区室 (2TCM) 和 Patlak 分析获得的动力学常数和葡萄糖脑代谢率 (CMR)。
我们表明，双动静脉分流的纵向 AIF 可以以非常高的手术成功率获得（88%）。我们的结果提供了高度可重复的 AIF 测量，动物间变异性低（11%），动物内变异性低（5-10%），这些变异性包含在动力学模型中，因此可以有效地估计纵向速率常数和 CMR，而不会与双分流相关的偏差。我们的结果表明，纵向 IDIF 也可以无偏地随时间生成，但显示出更高的动物内不确定性。
我们已经证明了使用动脉分流方法进行纵向 AIF 测量和随后的准确动力学建模的可行性和高度可重复性。
