Department of Radiology, Mayo Clinic, Rochester, MN, United States; Department of Neurology, Charles University, 2(nd) Faculty of Medicine, Motol University Hospital, Prague, Czech Republic.
Department of Radiology, Mayo Clinic, Rochester, MN, United States; Department of Information Technology, Mayo Clinic, Rochester, MN, United States.
Neuroimage Clin. 2018 Jun 19;19:939-947. doi: 10.1016/j.nicl.2018.06.020. eCollection 2018.
Visually preserved metabolism in posterior cingulate cortex relative to hypometabolism in precuneus and cuneus, the , is a feature of dementia with Lewy bodies (DLB) on FDG-PET. Lower (posterior cingulate cortex/cuneus+precuneus; FDG-CISr) values have been associated with a higher Braak neurofibrillary tangle stage in autopsied DLB. Using voxel-wise analysis, we assessed the patterns of regional cortical perfusion and metabolism, and using an atlas-based approach, we measured perfusion cingulate island sign ratio on arterial spin labeling MRI (ASL-CISr), and its associations with FDG-CISr, uptake on tau-PET and clinical severity in DLB. Our study sample ( = 114) included clinically probable DLB patients ( = 19), age-matched patients with probable Alzheimer's disease dementia (AD; = 19) and matched controls ( = 76) who underwent MRI with 3-dimensional pseudo-continuous arterial spin labeling, 18F-FDG-PET and 18F-AV-1451 tau PET. Patterns of cortical perfusion and metabolism were derived from quantitative maps using Statistical Parametric Mapping. DLB patients showed hypoperfusion on ASL-MRI in precuneus, cuneus and posterior parieto-occipital cortices, compared to controls, and relatively spared posterior cingulate gyrus, similar to pattern of hypometabolism on FDG-PET. DLB patients had higher ASL-CISr and FDG-CISr than AD patients ( <0.001). ASL-CISr correlated with FDG-CISr in DLB patients ( = 0.67; =0.002). Accuracy of distinguishing DLB from AD patients was 0.80 for ASL-CISr and 0.91 for FDG-CISr. Lower ASL-CISr was moderately associated with a higher composite medial temporal AV-1451 uptake ( = -0.50; =0.03) in DLB. Lower perfusion in precuneus and cuneus was associated with worse global clinical scores. In summary, the pattern of cortical hypoperfusion on ASL-MRI is similar to hypometabolism on FDG-PET, and respective cingulate island sign ratios correlate with each other in DLB. Non-invasive and radiotracer-free ASL-MRI may be further developed as a tool for the screening and diagnostic evaluation of DLB patients in a variety of clinical settings where FDG-PET is not accessible.
后部扣带回皮层的代谢保持完好，而楔前叶和楔叶的代谢降低，这是路易体痴呆（DLB）在 FDG-PET 上的特征。较低的 （后部扣带回皮层/楔前叶+楔叶；FDG-CISr） 值与尸检 DLB 中更高的 Braak 神经纤维缠结阶段有关。使用体素分析，我们评估了区域性皮质灌注和代谢的模式，并使用基于图谱的方法，测量了动脉自旋标记 MRI（ASL-CISr）上的扣带回岛征比，及其与 FDG-CISr、tau-PET 摄取和 DLB 临床严重程度的相关性。我们的研究样本（n=114）包括临床可能的 DLB 患者（n=19）、年龄匹配的可能阿尔茨海默病痴呆（AD）患者（n=19）和匹配的对照（n=76），他们接受了 3 维伪连续动脉自旋标记、18F-FDG-PET 和 18F-AV-1451 tau PET 的 MRI 检查。皮质灌注和代谢模式是使用统计参数映射从定量图谱中得出的。与对照组相比，DLB 患者的 ASL-MRI 显示楔前叶、楔叶和后部顶枕叶皮质的灌注减少，而后部扣带回 gyrus 相对保留，与 FDG-PET 上的代谢减少模式相似。DLB 患者的 ASL-CISr 和 FDG-CISr 高于 AD 患者（p<0.001）。DLB 患者的 ASL-CISr 与 FDG-CISr 相关（r=0.67；p=0.002）。ASL-CISr 区分 DLB 与 AD 患者的准确率为 0.80，FDG-CISr 为 0.91。DLB 患者中，较低的 ASL-CISr 与较高的内侧颞叶 AV-1451 摄取复合评分中度相关（r=-0.50；p=0.03）。楔前叶和楔叶的灌注降低与全球临床评分较差相关。总之，ASL-MRI 上皮质灌注减少的模式与 FDG-PET 上的代谢减少相似，DLB 中相应的扣带回岛征比相互相关。非侵入性和无放射性示踪剂的 ASL-MRI 可能会进一步发展成为一种工具，用于在各种无法进行 FDG-PET 的临床环境中筛选和诊断评估 DLB 患者。
