METHODS: The retrospective study included 41 PSP patients, 21 with Richardson\'s syndrome (PSP-RS), 20 with variant PSP phenotypes (vPSP) and 46 sex- and age-matched healthy controls. A pretrained support vector machine (SVM) for the classification of atrophy profiles from automatic MRI volumetry was used to analyse T1w-MRI (output: MRI-SVM-PSP score). Covariance pattern analysis was applied to compute the expression of a predefined PSP-related pattern in FDG-PET (output: PET-PSPRP expression score).
RESULTS: The area under the receiver operating characteristic curve for the detection of PSP did not differ between MRI-SVM-PSP and PET-PSPRP expression score (p≥0.63): about 0.90, 0.95 and 0.85 for detection of all PSP, PSP-RS and vPSP. The MRI-SVM-PSP score achieved about 13% higher specificity and about 15% lower sensitivity than the PET-PSPRP expression score. Decision tree models selected the MRI-SVM-PSP score for the first branching and the PET-PSPRP expression score for a second split of the subgroup with normal MRI-SVM-PSP score, both in the whole sample and when restricted to PSP-RS or vPSP.
CONCLUSIONS: FDG-PET provides added value for PSP-suspected patients with normal/inconclusive T1w-MRI, regardless of PSP phenotype and the methods to analyse the images for PSP-typical features.
方法:回顾性研究包括41例PSP患者,21患有理查森综合征(PSP-RS),具有变体PSP表型(vPSP)的20个和46个性别和年龄匹配的健康对照。使用预训练的支持向量机(SVM)对来自自动MRI容积法的萎缩谱进行分类,以分析T1w-MRI(输出:MRI-SVM-PSP评分)。应用协方差模式分析来计算FDG-PET中预定义的PSP相关模式的表达(输出:PET-PSPRP表达评分)。
结果:MRI-SVM-PSP和PET-PSPRP表达评分之间检测PSP的受试者工作特征曲线下面积没有差异(p≥0.63):检测所有PSP约为0.90、0.95和0.85,PSP-RS和vPSP。与PET-PSPRP表达评分相比,MRI-SVM-PSP评分的特异性高约13%,敏感性低约15%。决策树模型选择第一个分支的MRI-SVM-PSP评分和第二个分裂的具有正常MRI-SVM-PSP评分的亚组的PET-PSPRP表达评分,在整个样本中以及仅限于PSP-RS或vPSP时。
结论:FDG-PET为疑似PSP的T1w-MRI正常/不确定的患者提供了附加价值,无论PSP表型和分析PSP典型特征的图像的方法。