Department of Surgical Sciences, Uppsala University, Uppsala, Sweden; Medical Physics, Uppsala University Hospital, Uppsala, Sweden.
Department of Surgical Sciences, Uppsala University, Uppsala, Sweden; Department of Medicinal Chemistry, Uppsala University, Uppsala, Sweden.
Neuroimage Clin. 2019;22:101681. doi: 10.1016/j.nicl.2019.101681. Epub 2019 Jan 22.
[F]THK5317 is a PET tracer for in-vivo imaging of tau associated with Alzheimer's disease (AD). This work aimed to evaluate optimal timing for standardized uptake value ratio (SUVR) measures with [F]THK5317 and automated generation of SUVR-1 and relative cerebral blood flow (R) parametric images. Nine AD patients and nine controls underwent 90 min [F]THK5317 scans. SUVR-1 was calculated at transient equilibrium (TE) and for seven different 20 min intervals and compared with distribution volume ratio (DVR; reference Logan). Cerebellar grey matter (MRI) was used as reference region. A supervised cluster analysis (SVCA) method was implemented to automatically generate a reference region, directly from the dynamic PET volume without the need of a structural MRI scan, for computation of SUVR-1 and R images for a scan duration matching the optimal timing. TE was reached first in putamen, frontal- and parietal cortex at 22 ± 4 min for AD patients and in putamen at 20 ± 0 min in controls. Over all regions and subjects, SUVR-1 correlated best with DVR-1, R = 0.97. High correlation was found between values generated using MRI- and SVCA-based reference (R = 0.93 for SUVR-1; R = 0.94 for R). SUVR allows for accurate semi-quantitative assessment of tau pathology and SVCA may be used to obtain a reference region for calculation of both SUVR-1 and R with 40 min scan duration.
[F]THK5317 是一种用于阿尔茨海默病（AD）相关 tau 的体内成像的正电子发射断层扫描（PET）示踪剂。本研究旨在评估[F]THK5317 的标准化摄取值比（SUVR）测量的最佳时间，并自动生成 SUVR-1 和相对脑血流（R）参数图像。9 名 AD 患者和 9 名对照者接受了 90 分钟[F]THK5317 扫描。在瞬态平衡（TE）和 7 个不同的 20 分钟间隔计算 SUVR-1，并与分布容积比（DVR；参考 Logan）进行比较。小脑灰质（MRI）用作参考区。实施了监督聚类分析（SVCA）方法，该方法可从动态 PET 体积中自动生成参考区，而无需进行结构 MRI 扫描，以用于计算与最佳时间匹配的扫描持续时间的 SUVR-1 和 R 图像。在 AD 患者中，纹状体、额皮质和顶叶皮质在 22±4 分钟达到 TE，而在对照组中在纹状体中在 20±0 分钟达到 TE。在所有区域和受试者中，SUVR-1 与 DVR-1 相关性最佳，R=0.97。使用 MRI 和 SVCA 基于参考的方法生成的值之间相关性较高（SUVR-1 为 R=0.93；R 为 R=0.94）。SUVR 可用于准确评估 tau 病理学的半定量评估，SVCA 可用于获得参考区，以计算 40 分钟扫描时间的 SUVR-1 和 R。
