Department of Nuclear Medicine, University Hospital, LMU Munich, Munich, Germany.
Department of Neurology, University Hospital, LMU Munich, Munich, Germany.
Eur J Nucl Med Mol Imaging. 2024 Mar;51(4):1023-1034. doi: 10.1007/s00259-023-06493-w. Epub 2023 Nov 16.
Metabolic network analysis of FDG-PET utilizes an index of inter-regional correlation of resting state glucose metabolism and has been proven to provide complementary information regarding the disease process in parkinsonian syndromes. The goals of this study were (i) to evaluate pattern similarities of glucose metabolism and network connectivity in dementia with Lewy bodies (DLB) subjects with subthreshold dopaminergic loss compared to advanced disease stages and to (ii) investigate metabolic network alterations of FDG-PET for discrimination of patients with early DLB from other neurodegenerative disorders (Alzheimer's disease, Parkinson's disease, multiple system atrophy) at individual patient level via principal component analysis (PCA).
FDG-PETs of subjects with probable or possible DLB (n = 22) without significant dopamine deficiency (z-score < 2 in putamen binding loss on DaT-SPECT compared to healthy controls (HC)) were scaled by global-mean, prior to volume-of-interest-based analyses of relative glucose metabolism. Single region metabolic changes and network connectivity changes were compared against HC (n = 23) and against DLB subjects with significant dopamine deficiency (n = 86). PCA was applied to test discrimination of patients with DLB from disease controls (n = 101) at individual patient level.
Similar patterns of hypo- (parietal- and occipital cortex) and hypermetabolism (basal ganglia, limbic system, motor cortices) were observed in DLB patients with and without significant dopamine deficiency when compared to HC. Metabolic connectivity alterations correlated between DLB patients with and without significant dopamine deficiency (R = 0.597, p < 0.01). A PCA trained by DLB patients with dopamine deficiency and HC discriminated DLB patients without significant dopaminergic loss from other neurodegenerative parkinsonian disorders at individual patient level (area-under-the-curve (AUC): 0.912).
Disease-specific patterns of altered glucose metabolism and altered metabolic networks are present in DLB subjects without significant dopaminergic loss. Metabolic network alterations in FDG-PET can act as a supporting biomarker in the subgroup of DLB patients without significant dopaminergic loss at symptoms onset.
FDG-PET 的代谢网络分析利用了静息状态葡萄糖代谢的区域间相关指数，已被证明可提供帕金森综合征疾病过程的补充信息。本研究的目的是：（i）评估具有亚阈值多巴胺能丧失的路易体痴呆（DLB）受试者的葡萄糖代谢和网络连通性模式与疾病晚期的相似性；（ii）通过主成分分析（PCA）研究 FDG-PET 代谢网络改变，以在个体患者水平上区分早期 DLB 患者与其他神经退行性疾病（阿尔茨海默病、帕金森病、多系统萎缩）。
对无明显多巴胺缺乏（与健康对照组相比，DaT-SPECT 纹状体结合损失的 z 分数＜2）的可能或可能的 DLB 受试者（n=22）的 FDG-PET 进行全局均值标度，然后进行相对葡萄糖代谢的感兴趣区分析。与健康对照组（n=23）和明显多巴胺缺乏的 DLB 受试者（n=86）相比，比较了单个区域代谢变化和网络连通性变化。PCA 用于在个体患者水平上测试区分 DLB 患者与疾病对照组（n=101）。
与健康对照组相比，具有和不具有明显多巴胺缺乏的 DLB 患者均观察到代谢低下（顶叶和枕叶皮层）和代谢亢进（基底节、边缘系统、运动皮层）的相似模式。DLB 患者之间存在代谢连通性改变（r=0.597，p＜0.01）。由具有明显多巴胺缺乏的 DLB 患者和健康对照组训练的 PCA 可在个体患者水平上区分无明显多巴胺能丧失的 DLB 患者与其他神经退行性帕金森病（曲线下面积（AUC）：0.912）。
在无明显多巴胺能丧失的 DLB 患者中存在改变的葡萄糖代谢和改变的代谢网络的疾病特异性模式。FDG-PET 中的代谢网络改变可作为无明显多巴胺能丧失的 DLB 患者在症状发作时的支持性生物标志物。
