Department of Nuclear Medicine, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan.
Department of Neurology, Cognition and Aging Center, Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiw, Taiwan.
BMC Med Imaging. 2024 Mar 28;24(1):75. doi: 10.1186/s12880-024-01256-x.
Based on a longitudinal cohort design, the aim of this study was to investigate whether individual-based F fluorodeoxyglucose positron emission tomography (F-FDG-PET) regional signals can predict dementia conversion in patients with mild cognitive impairment (MCI).
We included 44 MCI converters (MCI-C), 38 non-converters (MCI-NC), 42 patients with Alzheimer's disease with dementia, and 40 cognitively normal controls. Data from annual cognitive measurements, 3D T1 magnetic resonance imaging (MRI) scans, and F-FDG-PET scans were used for outcome analysis. An individual-based FDG-PET approach was applied using seven volumes of interest (VOIs), Z transformed using a normal FDG-PET template. Hypometabolism was defined as a Z score < -2 of regional standard uptake value ratio. For the longitudinal cognitive test scores, generalized estimating equations were used. A linear mixed-effects model was used to compare the temporal impact of cortical hypometabolism and cortical thickness degeneration.
The clinical follow-up period was 6.6 ± 3.8 years (range 3.1 to 16.0 years). The trend of cognitive decline could differentiate MCI-C from MCI-NC after 3 years of follow-up. In the baseline 18F-FDG-PET scan of the patients with MCI, medial temporal lobe (MTL; 94.7% sensitivity, 80.5% specificity) and posterior cingulate cortex (PCC; 89.5% sensitivity, 73.1% specificity) hypometabolism predicted conversion with high accuracy. F-FDG-PET hypometabolism preceded dementia conversion at an interval of 3.70 ± 1.68 years and was earlier than volumetric changes, with the exception of the MTL.
Our finding supports the use of individual-based F-FDG-PET analysis to predict MCI conversion to dementia. Reduced FDG-PET metabolism in the MTL and PCC were strongly associated with future cognitive decline in the MCI-C group. Changes in F-FDG-PET occurred 1 to 8 years prior to conversion to dementia. Progressive hypometabolism in the PCC, precuneus and lateral temporal lobe, but not MTL, preceded MRI findings at the MCI stage.
基于纵向队列设计，本研究旨在探讨个体氟-18 氟代脱氧葡萄糖正电子发射断层扫描（F-FDG-PET）的区域信号是否可以预测轻度认知障碍（MCI）患者向痴呆的转化。
我们纳入了 44 名 MCI 转化者（MCI-C）、38 名非转化者（MCI-NC）、42 名阿尔茨海默病伴痴呆患者和 40 名认知正常对照者。使用年度认知测量、3D T1 磁共振成像（MRI）扫描和 F-FDG-PET 扫描的数据进行结果分析。使用 7 个感兴趣区（VOI）进行个体 FDG-PET 方法，使用正常 FDG-PET 模板进行 Z 变换。低代谢定义为区域标准摄取比值的 Z 分数< -2。对于纵向认知测试评分，使用广义估计方程。线性混合效应模型用于比较皮质下代谢和皮质厚度退化的时间影响。
临床随访时间为 6.6±3.8 年（范围 3.1 至 16.0 年）。在 3 年的随访后，认知衰退的趋势可以将 MCI-C 与 MCI-NC 区分开来。在 MCI 患者的基线 18F-FDG-PET 扫描中，内侧颞叶（MTL；94.7%的灵敏度，80.5%的特异性）和后扣带回皮层（PCC；89.5%的灵敏度，73.1%的特异性）低代谢具有高准确性预测转化。F-FDG-PET 低代谢在痴呆转化前的间隔为 3.70±1.68 年，早于体积变化，除 MTL 外。
我们的发现支持使用个体 F-FDG-PET 分析来预测 MCI 向痴呆的转化。MCI-C 组未来认知能力下降与 MTL 和 PCC 的 FDG-PET 代谢降低密切相关。F-FDG-PET 变化发生在向痴呆转化前 1 至 8 年。在 MCI 阶段，PCC、楔前叶和外侧颞叶的进行性低代谢先于 MRI 发现，而 MTL 则不然。
