Bauer Theresa, Brendel Matthias, Zaganjori Mirlind, Bernhardt Alexander M, Jäck Alexander, Stöcklein Sophia, Scheifele Maximilian, Levin Johannes, van Eimeren Thilo, Drzezga Alexander, Sabri Osama, Barthel Henryk, Perneczky Robert, Höglinger Günter, Franzmeier Nicolai, Gnörich Johannes
Department of Nuclear Medicine, University Hospital, LMU Munich, Munich, Germany.
Department of Nuclear Medicine, University Hospital, LMU Munich, Munich, Germany; German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany; Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.
Neuroimage. 2025 Feb 1;306:121001. doi: 10.1016/j.neuroimage.2025.121001. Epub 2025 Jan 9.
Standardized evaluation of [F]PI-2620 tau-PET scans in 4R-tauopathies represents an unmet need in clinical practice. This study aims to investigate the effectiveness of visual evaluation of [F]PI-2620 images for diagnosing 4R-tauopathies and to develop a straight-forward reading algorithm to improve objectivity and data reproducibility.
A total of 83 individuals with [F]PI-2620 PET scans were included. Participants were classified as probable 4R-tauopathies (n = 29), Alzheimer's disease (AD) (n = 20), α-synucleinopathies (n = 15), and healthy controls (n = 19) based on clinical criteria. Visual assessment of tau-PET scans (choice: 4R-tauopathy, AD-tauopathy, no-tauopathy) was conducted using either 20-40-minute or 40-60-minute intervals, with raw (common) and cerebellar grey matter scaled standardized reading settings (intensity-scaled). Two readers evaluated scans independently and blinded, with a third reader providing consensus in case of discrepant primary evaluation. A regional analysis was performed using the cortex, basal ganglia, midbrain, and dentate nucleus. Sensitivity, specificity, and interrater agreement were calculated for all settings and compared against the visual reads of parametric images (0-60-minutes, distribution volume ratios, DVR).
Patients with 4R-tauopathies in contrast to non-4R-tauopathies were detected at higher sensitivity in the 20-40-minute frame (common: 79%, scaled: 76%) compared to the 40-60-minute frame (common: 55%, scaled: 62%), albeit with reduced specificity in the common setting (20-40-min: 78%, 40-60-min: 95%), which was ameliorated in the intensity-scaled setting (20-40-min: 91%, 40-60-min: 96%). Combined assessment of multiple brain regions did not significantly improve diagnostic sensitivity, compared to assessing the basal ganglia alone (76% each). Evaluation of intensity-scaled parametric images resulted in higher sensitivity compared to intensity-scaled static scans (86% vs. 76%) at similar specificity (89% vs. 91%).
Visual reading of [F]PI-2620 tau-PET scans demonstrated reliable detection of 4R-tauopathies, particularly when standardized processing methods and early imaging windows were employed. Parametric images should be preferred for visual assessment of 4R-tauopathies.
在临床实践中，对4R- tau蛋白病的[F]PI-2620 tau正电子发射断层扫描（PET）进行标准化评估是一项尚未满足的需求。本研究旨在探讨对[F]PI-2620图像进行视觉评估以诊断4R- tau蛋白病的有效性，并开发一种简单的阅读算法以提高客观性和数据可重复性。
共纳入83例进行了[F]PI-2620 PET扫描的个体。根据临床标准，参与者被分为可能的4R- tau蛋白病（n = 29）、阿尔茨海默病（AD，n = 20）、α-突触核蛋白病（n = 15）和健康对照（n = 19）。tau-PET扫描的视觉评估（选择：4R- tau蛋白病、AD- tau蛋白病、无tau蛋白病）使用20至40分钟或40至60分钟间隔进行，并采用原始（普通）和小脑灰质缩放标准化阅读设置（强度缩放）。两名阅片者独立且盲法评估扫描结果，如有主要评估结果不一致，则由第三名阅片者达成共识。使用皮质、基底神经节、中脑和齿状核进行区域分析。计算所有设置下的敏感性、特异性和阅片者间一致性，并与参数图像（0至60分钟，分布容积比，DVR）的视觉读数进行比较。
与非4R- tau蛋白病患者相比，4R- tau蛋白病患者在20至40分钟帧（普通：79%，缩放：76%）中的检测敏感性高于40至60分钟帧（普通：55%，缩放：62%），尽管在普通设置下特异性降低（20至40分钟：78%，40至60分钟：95%），而在强度缩放设置下有所改善（20至40分钟：91%，40至60分钟：96%）。与单独评估基底神经节相比（均为76%），多个脑区的联合评估并未显著提高诊断敏感性。在相似的特异性（89%对91%）下，强度缩放参数图像的评估比强度缩放静态扫描具有更高的敏感性（86%对76%）。
对[F]PI-2620 tau-PET扫描进行视觉阅读显示，对4R- tau蛋白病的检测可靠，特别是在采用标准化处理方法和早期成像窗口时。对于4R- tau蛋白病的视觉评估，应优先选择参数图像。
