Kato A, Diksic M, Yamamoto Y L, Strother S C, Feindel W
J Cereb Blood Flow Metab. 1984 Dec;4(4):555-63. doi: 10.1038/jcbfm.1984.80.
A new experimental approach was designed to measure regional rate constants for [18F]2-fluoro-2-D-deoxyglucose in the three-compartment model. A programmed infusion was used to keep the plasma tracer concentration constant for the first 20 min. Positron emission tomography images of the brain were taken every minute for 20 min in a low-resolution mode, then every 15-20 min for 2-3 h in a medium-resolution mode. Two simplified operational equations for the calculation of the regional rate constants were derived that incorporated the contribution of the vascular compartment to tissue activity. The first equation was applied to data collected during the initial 20 min (when the concentration of plasma tracer was constant) to estimate the values of k1*, k2*, k3*, and the fraction of the vascular compartment. The second equation was applied to data collected during the whole experimental period to find the value of k4* and to provide a better estimate of k3*. The regional rate constants measured experimentally in three dogs and a brain tumor patient agreed well with those in the literature. This method permits estimation of the local CMRglu under pathological conditions using regionally measured rate constants and provides new information on the pathophysiological meaning of the rate constants.
设计了一种新的实验方法来测量三房室模型中[18F]2-氟-2-D-脱氧葡萄糖的区域速率常数。采用程序输注在最初20分钟内保持血浆示踪剂浓度恒定。以低分辨率模式每分钟采集一次大脑的正电子发射断层扫描图像，持续20分钟，然后以中等分辨率模式每15 - 20分钟采集一次，持续2 - 3小时。推导了两个简化的运算方程来计算区域速率常数，其中纳入了血管房室对组织活性的贡献。第一个方程应用于最初20分钟（血浆示踪剂浓度恒定时）收集的数据，以估计k1*、k2*、k3的值以及血管房室的分数。第二个方程应用于整个实验期间收集的数据，以求出k4的值并更好地估计k3*。在三只狗和一名脑肿瘤患者身上实验测量的区域速率常数与文献中的结果吻合良好。该方法允许使用区域测量的速率常数在病理条件下估计局部葡萄糖代谢率，并提供有关速率常数病理生理意义的新信息。
