Dataset Information

Tau-positron emission tomography correlates with neuropathology findings.

ABSTRACT:

Introduction

Comparison of tau (flortaucipir) positron emission tomography (FTP-PET) to autopsy is important to demonstrate the relationship of FTP-PET to neuropathologic findings.

Methods

Autopsies were performed on 26 participants who had antemortem FTP-PET. FTP-PET standardized uptake value ratios (SUVRs) were compared to autopsy diagnoses and Braak tangle stage. Quantitative tau burden was compared to regional FTP-PET signal.

Results

Participants with Braak stages of IV or greater had elevated FTP-PET signal. FTP-PET was elevated in participants with Alzheimer's disease. An FTP-PET SUVR cut point of 1.29 was determined to be optimal. Quantitative measurements of hippocampal and temporal lobe tau burden were highly correlated to FTP-PET signal (rho's from 0.61 to 0.70, P ≤ .02).

Discussion

Elevated FTP-PET reflects Braak IV or greater neuropathology. Participants with primary age-related tauopathy and hippocampal sclerosis did not show elevated FTP-PET signal. Secondary neuropathologic diagnoses of Alzheimer's disease neuropathologic change can lead to borderline elevated FTP-PET signal.

SUBMITTER: Lowe VJ

PROVIDER: S-EPMC7067654 | biostudies-literature |

REPOSITORIES: biostudies-literature

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