Buiter Hans J C, van Velden Floris H P, Leysen Josée E, Fisher Abraham, Windhorst Albert D, Lammertsma Adriaan A, Huisman Marc C
Department of Nuclear Medicine & PET Research, VU University Medical Center, P.O. Box 7057, 1007 MB Amsterdam, The Netherlands.
Int J Mol Imaging. 2012;2012:580717. doi: 10.1155/2012/580717. Epub 2012 Sep 23.
Background. An important step in the analysis of positron emission tomography (PET) studies of the brain is the definition of regions of interest (ROI). Image coregistration, ROI analysis, and quantification of brain PET data in small animals can be observer dependent. The purpose of this study was to investigate the feasibility of ROI analysis based on a standard MR template and an additional [(18)F]NaF scan. Methods. [(18)F]NaF scans of 10 Wistar rats were coregistered with a standard MR template by 3 observers and derived transformation matrices were applied to corresponding [(11)C]AF150(S) images. Uptake measures were derived for several brain regions delineated using the MR template. Overall agreement between the 3 observers was assessed by interclass correlation coefficients (ICC) of uptake data. In addition, [(11)C]AF150(S) ROI data were compared with ex vivo biodistribution data. Results. For all brain regions, ICC analysis showed excellent agreement between observers. Reproducibility, estimated by calculation of standard deviation of the between-observer differences, was demonstrated by an average of 17% expressed as coefficient of variation. Uptake of [(11)C]AF150(S) derived from ROI analysis closely matched ex vivo biodistribution data. Conclusions. The proposed method provides a reproducible and tracer-independent method for ROI analysis of rat brain PET data.
背景。脑正电子发射断层扫描（PET）研究分析中的一个重要步骤是定义感兴趣区域（ROI）。小动物脑PET数据的图像配准、ROI分析和定量可能依赖于观察者。本研究的目的是探讨基于标准MR模板和额外的[（18）F]NaF扫描进行ROI分析的可行性。方法。3名观察者将10只Wistar大鼠的[（18）F]NaF扫描图像与标准MR模板进行配准，并将得到的变换矩阵应用于相应的[（11）C]AF150（S）图像。使用MR模板勾勒出几个脑区，并得出摄取测量值。通过摄取数据的组内相关系数（ICC）评估3名观察者之间的总体一致性。此外，将[（11）C]AF150（S）ROI数据与离体生物分布数据进行比较。结果。对于所有脑区，ICC分析显示观察者之间具有极好的一致性。通过计算观察者间差异的标准差来估计的可重复性，以变异系数表示平均为17%。ROI分析得出的[（11）C]AF150（S）摄取与离体生物分布数据密切匹配。结论。所提出的方法为大鼠脑PET数据的ROI分析提供了一种可重复且与示踪剂无关的方法。
