Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; Leipzig University Medical Center, IFB Adiposity Diseases, Leipzig, Germany; Department of Medical Engineering and Biotechnology, University of Applied Science, Jena, Germany.
Neuroimage Clin. 2019;21:101594. doi: 10.1016/j.nicl.2018.11.004. Epub 2018 Nov 15.
Recently, revised diagnostic criteria for Parkinson's disease (PD) were introduced (Postuma et al., 2015). Yet, except for well-established dopaminergic imaging, validated imaging biomarkers for PD are still missing, though they could improve diagnostic accuracy. We conducted systematic meta-analyses to identify PD-specific markers in whole-brain structural magnetic resonance imaging (MRI), [18F]-fluorodeoxyglucose-positron emission tomography (FDG-PET) and diffusion tensor imaging (DTI) studies. Overall, 74 studies were identified including 2323 patients and 1767 healthy controls. Studies were first grouped according to imaging modalities (MRI 50; PET 14; DTI 10) and then into subcohorts based on clinical phenotypes. To ensure reliable results, we combined established meta-analytical algorithms - anatomical likelihood estimation and seed-based D mapping - and cross-validated them in a conjunction analysis. Glucose hypometabolism was found using FDG-PET extensively in bilateral inferior parietal cortex and left caudate nucleus with both meta-analytic methods. This hypometabolism pattern was confirmed in subcohort analyses and related to cognitive deficits (inferior parietal cortex) and motor symptoms (caudate nucleus). Structural MRI showed only small focal gray matter atrophy in the middle occipital gyrus that was not confirmed in subcohort analyses. DTI revealed fractional anisotropy reductions in the cingulate bundle near the orbital and anterior cingulate gyri in PD. Our results suggest that FDG-PET reliably identifies consistent functional brain abnormalities in PD, whereas structural MRI and DTI show only focal alterations and rather inconsistent results. In conclusion, FDG-PET hypometabolism outperforms structural MRI in PD, although both imaging methods do not offer disease-specific imaging biomarkers for PD.
最近，修订版的帕金森病（PD）诊断标准已经出台（Postuma 等人，2015 年）。然而，除了已经确立的多巴胺能成像，PD 的验证性成像生物标志物仍然缺失，尽管它们可以提高诊断的准确性。我们进行了系统的荟萃分析，以确定全脑结构磁共振成像（MRI）、[18F]-氟脱氧葡萄糖正电子发射断层扫描（FDG-PET）和弥散张量成像（DTI）研究中的 PD 特异性标志物。总的来说，共确定了 74 项研究，包括 2323 名患者和 1767 名健康对照者。这些研究首先根据成像方式（MRI 50 项；PET 14 项；DTI 10 项）进行分组，然后根据临床表型分为亚组。为了确保可靠的结果，我们结合了已建立的荟萃分析算法——解剖似然估计和基于种子的 D 映射——并在联合分析中对其进行了交叉验证。使用 FDG-PET 在双侧顶下小叶和左侧尾状核广泛发现葡萄糖代谢低下，两种元分析方法均得到证实。在亚组分析中证实了这种代谢低下模式，并与认知缺陷（顶下小叶）和运动症状（尾状核）有关。结构 MRI 仅显示中枕叶的小焦点灰质萎缩，但在亚组分析中未得到证实。DTI 显示 PD 患者眶额和前扣带回附近扣带束的各向异性分数降低。我们的结果表明，FDG-PET 可靠地识别出 PD 中一致的功能性脑异常，而结构 MRI 和 DTI 仅显示出局灶性改变，且结果相当不一致。总之，尽管这两种成像方法都没有为 PD 提供特异性的成像生物标志物，但 FDG-PET 代谢低下在 PD 中优于结构 MRI。
