Sandell A, Ohlsson T, Erlandsson K, Strand S E
Department of Radiation Physics, University Hospital, Lund, Sweden.
J Nucl Med. 1998 Mar;39(3):552-5.
An alternative method of determining the integrated input function, necessary in the quantitative [18F]fluorodeoxyglucose (FDG) autoradiographic model, has been developed. Using erythrocytes as reference tissue, researchers require only one blood sample after injection of FDG to obtain the integrated input function.
The amount of FDG-6-PO4 in the erythrocytes is proportional to their exposure to FDG, that is, the integrated input function. Free FDG is removed by washing the erythrocytes twice. Inter- and intraindividual differences of the metabolic rate of erythrocytes are corrected for by an in vitro incubation with a known amount of FDG.
Validation of the proposed method was done by correlating the integrated input function, based on the glucose metabolism of the erythrocytes, to the integrated input function obtained by multiple venous blood samples. The new method provides the integrated input function with an accuracy better than +/-8%.
By using erythrocytes as a reference tissue, researchers can determine the integrated input function in the quantitative FDG autoradiographic model with an accuracy sufficient for clinical PET studies. The simplicity of the method also makes it suitable for FDG studies on small children. With two samples, the method can also be used for a simplified graphical Patlak analysis.
已开发出一种在定量[18F]氟脱氧葡萄糖（FDG）放射自显影模型中确定积分输入函数的替代方法。以红细胞作为参考组织，研究人员在注射FDG后仅需采集一份血样即可获得积分输入函数。
红细胞中FDG-6-PO4的量与它们对FDG的暴露量成正比，即与积分输入函数成正比。通过洗涤红细胞两次可去除游离的FDG。通过与已知量的FDG进行体外孵育来校正个体间和个体内红细胞代谢率的差异。
通过将基于红细胞葡萄糖代谢的积分输入函数与通过多个静脉血样获得的积分输入函数进行关联，对所提出的方法进行了验证。新方法提供的积分输入函数的准确度优于±8%。
通过将红细胞用作参考组织，研究人员可以在定量FDG放射自显影模型中确定积分输入函数，其准确度足以用于临床PET研究。该方法的简单性也使其适用于对幼儿的FDG研究。使用两份样本，该方法还可用于简化的图形化Patlak分析。
