Neuroscience Research Center, Faculty of Medical Sciences, Lebanese University, Beirut, Lebanon.
Department of Biomedical Sciences, School of Pharmacy, Lebanese International University, Beirut, Lebanon.
BMC Neurol. 2023 Oct 24;23(1):385. doi: 10.1186/s12883-023-03432-y.
Dementia is generally caused by neurodegenerative diseases affecting the brain, which leads to a progressive neurocognitive decline characterized by inability to perform major higher functioning tasks. Fluorodeoxyglucose-positron emission tomography (FDG-PET) scan is one of the main imaging tests performed for diagnostic purposes. However, with FDG-PET being quite expensive and not widely available, an attempt to find an alternative is set. Arterial-spin-labelling magnetic resonance imaging (ASL-MRI) is an increasingly investigated substitute to FDG-PET for the diagnosis of dementia. Thereby, the main purpose of this systematic review and meta-analysis is to compare the diagnostic ability of FDG-PET and ASL-MRI in detecting dementia.
PRISMA checklist for diagnostic test accuracy was employed in outlining this paper. A literature search was done using several search engines including PubMed, Core, and Cochrane. Two researchers (HH and SH) extracted the essential information from all included articles. Risk of bias was evaluated by the Quality Assessment of Diagnostic Accuracy Studies tool, version 2 (QUADAS-2). A qualitative analysis and summary of studies' results were provided. In addition, a meta-analysis was executed based on the studies which involved sensitivity and specificity measures of diagnostic accuracy.
Fourteen total studies were included in the given review. Qualitative analysis of the articles showed that nine studies demonstrated an overlap between metabolic and perfused brain maps as derived by FDG-PET and ASL-MRI respectively, while the remaining five studies registered significant differences across both modalities, with superiority to FDG-PET. As for the meta-analysis implemented, summary ROC-curve analysis revealed that FDG-PET performed better than ASL-MRI, with pooled sensitivity being significantly higher for FDG-PET.
Comparing the diagnostic value of FDG-PET and ASL-MRI, the results of this systematic review and meta-analysis indicate that FDG-PET still has an advantage over ASL-MRI. Such implication could be related to the technical differences relating to both modalities, with ASL-MRI having lower temporal resolution. It's worth mentioning that specificity was rather quite similar among both modalities and some studies found an overridden metabolic and perfused images. These findings call for future research to focus their scope of investigation while exploring the diagnostic value of ASL-MRI.
痴呆症通常由影响大脑的神经退行性疾病引起，导致以无法执行主要高级功能任务为特征的进行性神经认知衰退。氟代脱氧葡萄糖正电子发射断层扫描（FDG-PET）扫描是为诊断目的而进行的主要成像测试之一。然而，由于 FDG-PET 非常昂贵且并非广泛可用，因此尝试寻找替代方法。动脉自旋标记磁共振成像（ASL-MRI）是 FDG-PET 用于诊断痴呆症的替代方法，越来越受到研究。因此，本系统评价和荟萃分析的主要目的是比较 FDG-PET 和 ASL-MRI 检测痴呆症的诊断能力。
采用 PRISMA 诊断测试准确性检查表概述本文。使用包括 PubMed、Core 和 Cochrane 在内的多个搜索引擎进行文献检索。两名研究人员（HH 和 SH）从所有纳入的文章中提取必要信息。使用质量评估诊断准确性研究工具（版本 2，QUADAS-2）评估偏倚风险。提供了研究结果的定性分析和总结。此外，根据涉及诊断准确性敏感性和特异性测量的研究，还执行了荟萃分析。
综述共纳入 14 项研究。对文章的定性分析表明，9 项研究显示 FDG-PET 和 ASL-MRI 分别得出的代谢和灌注脑图之间存在重叠，而其余 5 项研究在两种模式下均存在显著差异，且 FDG-PET 更具优势。对于实施的荟萃分析，汇总 ROC 曲线分析表明 FDG-PET 优于 ASL-MRI，FDG-PET 的汇总敏感性明显更高。
比较 FDG-PET 和 ASL-MRI 的诊断价值，本系统评价和荟萃分析的结果表明，FDG-PET 仍然优于 ASL-MRI。这种影响可能与两种模式的技术差异有关，ASL-MRI 的时间分辨率较低。值得注意的是，两种模式的特异性相当相似，一些研究发现代谢和灌注图像重叠。这些发现呼吁未来的研究在探索 ASL-MRI 的诊断价值时，将其研究范围集中在这方面。
