Gutierrez Albenda David, Ulate Blanco Paula, Murillo Julyana, Solano Brenes Juan J, Sánchez Hidalgo Nelson Mauricio
Cyclotron PET/CT Laboratory, University of Costa Rica, San José, CRI.
School of Medicine, Faculty of Medicine, University of Costa Rica, San José, CRI.
Cureus. 2025 Aug 11;17(8):e89795. doi: 10.7759/cureus.89795. eCollection 2025 Aug.
Neurodegenerative dementias comprise a heterogeneous group of diseases with distinct pathological substrates, among which Alzheimer's disease, dementia with Lewy bodies (DLB), and frontotemporal dementia are the most prominent. The early and accurate diagnosis of these conditions remains a clinical challenge, in which both structural and functional imaging techniques play crucial roles. This article presents a case of a 68-year-old female patient with progressive cognitive decline, evaluated using ¹⁸F-fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET), which revealed a characteristic pattern of symmetric hypometabolism in the temporal, parietal, and occipital lobes, with preserved metabolism in the posterior cingulate cortex (the cingulate island sign), a finding highly suggestive of DLB. This case highlights the value of ¹⁸F-FDG PET as a diagnostic tool in the differential evaluation of dementias and underscores the importance of recognizing the specific metabolic pattern of DLB to support timely clinical decision-making. The model incorporating visual and semi-quantitative parameters achieved a diagnostic accuracy of 84.3%.
神经退行性痴呆是一组具有不同病理基础的异质性疾病，其中阿尔茨海默病、路易体痴呆（DLB）和额颞叶痴呆最为突出。这些疾病的早期准确诊断仍然是一项临床挑战，结构和功能成像技术在其中都起着关键作用。本文介绍了一例68岁女性进行性认知衰退患者，使用¹⁸F-氟脱氧葡萄糖正电子发射断层扫描（¹⁸F-FDG PET）进行评估，结果显示颞叶、顶叶和枕叶出现对称性代谢减低的特征性模式，而后扣带回皮质代谢保留（扣带回岛征），这一发现高度提示DLB。该病例突出了¹⁸F-FDG PET作为痴呆鉴别评估诊断工具的价值，并强调了识别DLB特定代谢模式以支持及时临床决策的重要性。纳入视觉和半定量参数的模型诊断准确率达到84.3%。
