Abstract

Objective

[¹⁸F]-fluoro-2-deoxy-d-glucose positron emission tomography (¹⁸F-FDG PET) imaging and magnetic resonance imaging (MRI) of brain in ALS patients with frontotemporal lobe dementia (ALS-FTD) reveal hypometabolism and hypermetabolism, as well as gray matter (GM) and white matter (WM) abnormalities in different brain regions, respectively. Hypometabolism arising from neuronal dysfunction or loss is the most recognized pathophysiologic change in neurodegeneration, whereas mechanisms underlying hypermetabolism remain unclear. We hypothesize that hypometabolic and hypermetabolic brain regions in ALS-FTD represent differential degeneration of GM and WM structures, as revealed by co-registered MRI in a two time-point longitudinal multimodal study. Methods: A 69-year-old female with ALS-FTD underwent ¹⁸F-FDG PET, diffusion tensor imaging (DTI), and T1-weighted MRI at baseline (15 months after symptom onset), and 20.4 months later. Cerebral glucose metabolism rate, cortical thickness, cortical area, and WM network changes were measured longitudinally. Results and conclusion: The patient had symptoms and signs of bulbar-onset upper motor neuron (UMN)-predominant ALS with language and behavioral dysfunction. Evaluation at baseline showed bulbar dysfunction, and impaired language and executive function. At follow-up, worsened bulbar and other motor functions, and prominent FTD both reflected significant progression. Cortical thickness and surface area showed differential involvement in the hypometabolic and hypermetabolic regions. WM connections from frontal regions to other brain regions were completely absent by graph theory-based network analysis when compared to temporal regions indicating prominent frontal lobe degeneration. Structural neuroimaging reveals different patterns of GM and WM involvement in the hypometabolic and hypermetabolic brain regions in a patient with ALS-FTD.

中文翻译：

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ALS-FTD 患者代谢低下和代谢亢进大脑区域的灰质和白质变性有所不同：一项纵向 MRI - PET 多模式研究

 抽象的

 客观的

伴有额颞叶痴呆 (ALS-FTD) 的 ALS 患者脑部 [ ¹⁸ F]-氟-2-脱氧-d-葡萄糖正电子发射断层扫描 ( ¹⁸ F-FDG PET) 成像和磁共振成像 (MRI) 揭示代谢低下和代谢亢进，以及不同大脑区域的灰质（GM）和白质（WM）异常。神经元功能障碍或丧失引起的代谢低下是神经变性中最常见的病理生理变化，而代谢亢进的机制仍不清楚。我们假设 ALS-FTD 中代谢低下和代谢亢进的大脑区域代表了 GM 和 WM 结构的差异性变性，正如在两个时间点纵向多模态研究中联合注册 MRI 所揭示的那样。方法：一名患有 ALS-FTD 的 69 岁女性在基线（症状出现后 15 个月）和 20.4 个月后接受了¹⁸ F-FDG PET、弥散张量成像 (DTI) 和 T1 加权 MRI。纵向测量大脑葡萄糖代谢率、皮质厚度、皮质面积和WM网络变化。结果和结论：患者有延髓发病的上运动神经元（UMN）为主的 ALS 症状和体征，伴有语言和行为功能障碍。基线评估显示延髓功能障碍以及语言和执行功能受损。在随访中，延髓和其他运动功能恶化以及显着的 FTD 都反映了显着的进展。皮质厚度和表面积在代谢低下和代谢亢进区域中表现出不同的参与程度。 与表明额叶明显退化的颞区相比，基于图论的网络分析完全不存在从额叶区域到其他大脑区域的 WM 连接。结构神经影像揭示了 ALS-FTD 患者代谢低下和代谢亢进大脑区域中 GM 和 WM 参与的不同模式。