Related Experiment Video
Updated: Aug 31, 2026

Abbiategrasso Brain Bank Protocol for Collecting, Processing and Characterizing Aging Brains
Published on: June 3, 2020
[(18)F]THK-5117 PET for assessing neurofibrillary pathology in Alzheimer's disease
Ryuichi Harada1, Nobuyuki Okamura, Shozo Furumoto
1Division of Neuro-imaging, Institute of Development, Aging and Cancer, Tohoku University, Sendai, 980-8575, Japan.
Purpose:
Visualization of the spatial distribution of neurofibrillary tangles would help in the diagnosis, prevention and treatment of dementia. The purpose of the study was to evaluate the clinical utility of [(18)F]THK-5117 as a highly selective tau imaging radiotracer.
Methods:
We initially evaluated in vitro binding of [(3)H]THK-5117 in post-mortem brain tissues from patients with Alzheimer's disease (AD). In clinical PET studies, [(18)F]THK-5117 retention in eight patients with AD was compared with that in six healthy elderly controls. Ten subjects underwent an additional [(11)C]PiB PET scan within 2 weeks.
Results:
In post-mortem brain samples, THK-5117 bound selectively to neurofibrillary deposits, which differed from the binding target of PiB. In clinical PET studies, [(18)F]THK-5117 binding in the temporal lobe clearly distinguished patients with AD from healthy elderly subjects. Compared with [(11)C]PiB, [(18)F]THK-5117 retention was higher in the medial temporal cortex.
Conclusion:
These findings suggest that [(18)F]THK-5117 provides regional information on neurofibrillary pathology in living subjects.
Related Concept Videos
Alzheimer's Disease: Overview
The clinical diagnosis of AD hinges on the presence of memory and other cognitive impairments. Biomarkers, such as changes in Aβ and tau...
Alzheimer Disease ll: Pathophysiology
Dementia l: Introduction

