Buck A, Gucker P M, Schönbächler R D, Arigoni M, Kneifel S, Vollenweider F X, Ametamey S M, Burger C
PET Center, Division of Nuclear Medicine, University Hospital, Zurich, Switzerland.
J Cereb Blood Flow Metab. 2000 Feb;20(2):253-62. doi: 10.1097/00004647-200002000-00005.
11CMcN-5652 is an established positron emission tomography tracer used to assess serotonergic transporter density. Several methods have been used to analyze 11CMcN-5652 data; however, no evaluation of candidate methods has been published in detail yet. In this study, compartmental modeling using a one-tissue compartment model (K1, k2"), a two-tissue compartment model (K1 to k4), and a noncompartmental method that relies on a reference region devoid of specific binding sites were assessed. Because of its low density of serotonergic transporters, white matter was chosen as reference. Parameters related to transporter density were the total distribution volume DV" (= K1/k2", one tissue compartment), DVtot, (=K1/k1' (1 + k3/k4), two tissue compartments), and Rv (= k3'/k4, noncompartmental method). The DV", DVtot, and Rv values extended over a similar range and reflected the known pattern of serotonergic transporters. However, all parameters related to transporter density were markedly confounded by nonspecific binding. With regard to K1, the one-tissue compartment model yielded markedly lower values, which were, however, more stable. The minimal study duration needed to determine stable values for the distribution volume was approximately 60 minutes. The choice of the method to analyze 11CMcN-5652 data depends on the situation. Parametric maps of Rv are useful if no information on K1 is needed. If compartmental modeling is chosen, both the one- and the two-tissue compartment models have advantages. The one-tissue compartment model underestimates K1 but yields more robust values. The distribution volumes calculated with both models contain a similar amount of information. None of the parameters reflected serotonergic transporter density in a true quantitative manner, as all were confounded by nonspecific binding.
11CMcN - 5652是一种已确立的正电子发射断层扫描示踪剂，用于评估血清素转运体密度。已有多种方法用于分析11CMcN - 5652数据；然而，尚未有对候选方法的详细评估发表。在本研究中，评估了使用单组织隔室模型（K1，k2"）、双组织隔室模型（K1至k4）的隔室建模以及依赖于无特异性结合位点的参考区域的非隔室方法。由于血清素转运体密度较低，选择白质作为参考。与转运体密度相关的参数为总分布容积DV"（= K1/k2"，单组织隔室）、DVtot（= K1/k1' (1 + k3/k4)，双组织隔室）和Rv（= k3'/k4，非隔室方法）。DV"、DVtot和Rv值在相似范围内扩展，并反映了已知的血清素转运体模式。然而，所有与转运体密度相关的参数都受到非特异性结合的显著混淆。关于K1，单组织隔室模型得出的值明显较低，不过更稳定。确定分布容积稳定值所需的最短研究持续时间约为60分钟。分析11CMcN - 5652数据的方法选择取决于具体情况。如果不需要关于K1的信息，Rv的参数图很有用。如果选择隔室建模，单组织和双组织隔室模型都有优势。单组织隔室模型低估了K1，但得出的值更稳健。用这两种模型计算的分布容积包含相似量的信息。没有一个参数以真正定量的方式反映血清素转运体密度，因为所有参数都受到非特异性结合的混淆。
