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O5‐01‐02: FUNCTIONAL BRAIN ARCHITECTURE PREDICTS LONGITUDINAL TAU SPREADING IN ALZHEIMER'S DISEASE
Author(s) -
Franzmeier Nicolai,
Neitzel Julia,
Rubinski Anna,
Ewers Michael
Publication year - 2019
Publication title -
alzheimer's and dementia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.713
H-Index - 118
eISSN - 1552-5279
pISSN - 1552-5260
DOI - 10.1016/j.jalz.2019.06.4835
Subject(s) - resting state fmri , entorhinal cortex , voxel , tau pathology , functional connectivity , neuroscience , alzheimer's disease , psychology , medicine , hippocampus , disease , radiology
O5-01-01 HEAD-TO-HEAD IN VIVO COMPARISON OF TAU POSITRON EMISSION TOMOGRAPHY LIGANDS FFLORTAUCIPIR AND F-RO948 Ruben Smith, Michael Sch€oll, Tomas Ohlsson, Jonas J€ogi, Olof Strandberg, Oskar Hansson, Clinical Memory ResearchUnit, Lund University, Malm€o, Sweden; Sk ane University Hospital, Lund, Sweden; Lund University, Malm€o, Sweden; Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Gothenburg, Sweden; University College London, London, United Kingdom; Memory Clinic, Sk ane University Hospital, Lund, Sweden; ClinicalMemory ResearchUnit, Department of Clinical Sciences, Malm€o, Lund University, Lund, Sweden. Contact e-mail: ruben.smith@med.lu.se Background: F-Flortaucipir (FTP) is the most widely used PET ligand for the in vivo assessment of tau pathology. It binds to paired-helical filament tau and has been shown to be useful in the diagnosis of AD. However, off-target binding e.g. in the choroid plexus and the basal ganglia hamper accurate quantification of FTP in these and adjacent regions. Recently, several other tau PET ligands have been developed. Here, we compare 18F-FTP with the novel tau ligand F-RO948 head-to-head in vivo. Methods: Within this study, 33 individuals have undergone FFTP PET at 80-100 min and F-RO948 at 7090 min post ligand injection. Four subjects have undergone dynamic scanning 0-100 min. Subject diagnoses were: 18 AD (Abpositive), three MCI (Ab positive), four Progressive Supranuclear Palsy patients, three with semantic variant Primary Progressive Aphasia, one Dementia with Lewy Bodies and four neurologically healthy controls (mean age 71.6 6 8.2 y). The average time between PET scans was 21 6 41 days. Standardized uptake value ratios (SUVR) were created using an inferior cerebellar reference region. Results: The neocortical retention of the two radioligands was highly similar when assessed using SUVR-values. A small, but significant, increase in retention was found in the entorhinal cortex (Braak stage I-II) using F-RO948 (Figure 1). On visual inspection, F-RO948 uptake was substantially lower in the basal ganglia, the thalamus, and the choroid plexus, but not in the substantia nigra compared to F-FTP uptake (Figure 2). Statistical comparison confirmed significantly lower F-RO948 uptake in the choroid plexus and the basal ganglia (Figure 3). However, some cases exhibited strong F-RO948 signal in the skull or the meninges, which was not observed for F-FTP, and at a group level the skull/meningeal binding was significantly higher in the F-RO948 scans. Conclusions: F-RO948 and F-FTP performed very similarly in neocortical target regions, whereas F-RO948 showed a lower binding to the well-known off target regions for F-FTP (basal ganglia, thalamus and choroid plexus). Instead F-RO948 showed a higher offtarget uptake in the skull/meninges compared to F-FTP.