Presotto Luca, Ballarini Tommaso, Caminiti Silvia Paola, Bettinardi Valentino, Gianolli Luigi, Perani Daniela
Division of Neuroscience, In vivo human molecular and structural neuroimaging unit, IRCCS San Raffaele Scientific Institute, Milan, Italy.
Vita-Salute San Raffaele University, Via Olgettina 60, 20132, Milan, Italy.
Neuroinformatics. 2017 Apr;15(2):151-163. doi: 10.1007/s12021-016-9322-9.
F-fluoro-deoxy-glucose Positron Emission Tomography (FDG-PET) allows early identification of neurodegeneration in dementia. The use of an optimized method based on the SPM software package highly improves diagnostic accuracy. However, the impact of different scanners for data acquisition on the SPM results and the effects of different pools of healthy subjects on the statistical comparison have not been investigated yet. Images from 144 AD patients acquired using six different PET scanners were analysed with an optimized single-subject SPM procedure to identify the typical AD hypometabolism pattern at single subject level. We compared between-scanners differences on the SPM outcomes in a factorial design. Single-subject SPM comparison analyses were also performed against a different group of healthy controls from the ADNI initiative. The concordance between the two analyses (112 vs. 157 control subjects) was tested using Dice scores. In addition, we applied the optimized single-subject SPM procedure to the FDG-PET data acquired with 3 different scanners in 57 MCI subjects, in order to assess for tomograph influence in early disease phase. All the patients showed comparable AD-like hypometabolic patterns, also in the prodromal phase, in spite of being acquired with different PET scanners. SPM statistical comparisons performed with the two different healthy control databases showed a high degree of concordance (76% average pattern volume overlap and 90% voxel-wise agreement in AD-related brain structures). The validated optimized SPM-based single-subject procedure is influenced neither by the scanners used for image acquisition, nor by differences in healthy control groups, thus implying a great reliability of this method for longitudinal and multicentre studies.
氟代脱氧葡萄糖正电子发射断层扫描（FDG-PET）能够早期识别痴呆中的神经退行性变。基于统计参数映射（SPM）软件包的优化方法的使用极大地提高了诊断准确性。然而，不同的数据采集扫描仪对SPM结果的影响以及不同健康受试者群体对统计比较的影响尚未得到研究。使用六种不同的PET扫描仪采集的144例阿尔茨海默病（AD）患者的图像，采用优化的单受试者SPM程序进行分析，以在单受试者水平上识别典型的AD代谢减低模式。我们在析因设计中比较了扫描仪之间在SPM结果上的差异。还针对来自阿尔茨海默病神经影像学计划（ADNI）倡议的另一组健康对照进行了单受试者SPM比较分析。使用骰子系数测试了两种分析（112名与157名对照受试者）之间的一致性。此外，我们将优化的单受试者SPM程序应用于57例轻度认知障碍（MCI）受试者用3种不同扫描仪采集的FDG-PET数据，以评估断层扫描仪在疾病早期阶段的影响。尽管这些患者的图像是用不同的PET扫描仪采集的，但所有患者在疾病前驱期也都表现出类似AD的代谢减低模式。使用两个不同的健康对照数据库进行的SPM统计比较显示出高度一致性（在与AD相关的脑结构中，平均模式体积重叠率为76%，体素水平一致性为90%）。经过验证的基于SPM的优化单受试者程序既不受用于图像采集的扫描仪的影响，也不受健康对照组差异的影响，因此意味着该方法在纵向和多中心研究中具有很高的可靠性。
