SNMMI image of the year: In vivo selective imaging of tau pathology in Alzheimer's disease with F-18

June 10, 2014, Society of Nuclear Medicine

A PET image using F-18 THK5117, a novel tracer that labels neurofibrillary tangles with high selectivity, has been selected as the Society of Nuclear Medicine and Molecular Imaging's (SNMMI) 2014 Image of the Year. Researchers selected this image from more than 1,700 studies presented during the 2014 SNMMI Annual Meeting in St. Louis, Mo. Each year, SNMMI chooses an image that exemplifies the most cutting-edge nuclear medicine or molecular imaging research today and demonstrates the ability of molecular imaging to detect, diagnose and treat disease and help select the most appropriate therapy.

Dementia affects nearly 40 million people worldwide, and Alzheimer's disease (AD) is the leading form of dementia. There are two distinct pathological changes seen in Alzheimer's brain—senile plaques, which have amyloid deposition, and neurofibrillary tangles, which have hyperphosphorylated tau deposition. In comparison to well-established amyloid PET tracers, radiotracers that bind to tau/neurofibrillary tangles are still under development.

During the study, Nobuyuki Okamura, MD, PhD, of Tohoku University School of Medicine and his team had eight AD patients and six age-matched healthy control (HC) subjects undergo F-18 THK5117 PET scans for 90 minutes. PET scans were performed with C-11 Pittsburgh Compound B (PiB) on the same population. Standard uptake value ratios (SUVRs) were calculated 60-80 minutes post-injection for THK5117 and 40-70 minutes post-injection for PiB using the cerebellar cortex as the reference region. Partial volume correction, accounting for both grey matter atrophy and white matter spillover, was performed using PMOD 3.4 software.

"In this study, the selective binding ability of F-18 THK5117 to tau was confirmed by the direct comparison with the amyloid PET tracer PiB." stated Okamura. "I hope that this technique will contribute to the development of new anti-dementia drugs. I feel very honored to receive this award. I would like to thank all the team members and subjects who participated in this research project."

AD patients showed F-18 THK5117 retention in the lateral and medial temporal cortices, areas known to contain high concentrations of tau deposits. F-18 THK5117 SUVR in these areas reached a plateau at 60 minutes post-injection. Regional distribution of F-18 THK5117 differed considerably from that of C-11 PiB in AD brains. F-18 THK5117 retention in the temporal cortex was correlated with the severity of dementia. In addition, F-18 THK5117 retention in the hippocampus was correlated with hippocampal volume in AD patients. Intriguingly, F-18 THK5117 retention in the right temporal lobe was observed in HC subjects with right temporal lobe atrophy.

"Dr. Okamura's work is in the forefront of such research." noted Satoshi Minoshima, MD, PhD, chair of the SNMMI Scientific Program Committee. "His group has successfully developed an F-18 labeled tracer, F-18 THK5117, that binds to tau/ seen in Alzheimer's disease. Owing to its longer half life, F-18 labeled tracers can potentially be distributed widely to many imaging centers. They demonstrated differential distributions of amyloid tracer versus tau/neurofibrillary tangle tracer in Alzheimer patients. Such observations shed critical light into pathogenesis and pathophysiology of Alzheimer's disease and will help develop better diagnostic methods and effective treatments."

Explore further: Depression in the elderly linked to Alzheimer's risk

More information: Scientific Paper 136: N. Okamura, R. Harada, and K. Yanai, Tohoku University School of Medicine, Sendai, Japan; S. Furumoto, R. Iwata, and M. Tashiro, Cyclotron and Radiosotope Center, Tohoku University, Sendai, Japan; K. Furukawa, A. Ishiki, and H. Arai, Institute of Development, Aging and Cancer, Tohoku University, Sendai Japan; and Y. Kudo, Clinical Research, Innovation and Education Center, Tohoku University Hospital, Sendai, Japan, "In vivo selective imaging of tau pathology in Alzheimer's Disease with 18F-THK5117." SNMMI Annual Meeting, June 7-11, 2014, St. Louis, Missouri.

Related Stories

Depression in the elderly linked to Alzheimer's risk

June 9, 2014
Many people develop depression in the latest stages of life, but until now doctors had no idea that it could point to a build up of a naturally occurring protein in the brain called beta-amyloid, a hallmark of Alzheimer's ...

Study examines amyloid deposition in patients with traumatic brain injury

November 11, 2013
Patients with traumatic brain injury (TBI) had increased deposits of β-Amyloid (Aβ) plaques, a hallmark of Alzheimer Disease (AD), in some areas of their brains in a study by Young T. Hong, Ph.D., of the University of Cambridge, ...

Fluorescent compounds allow clinicians to visualize Alzheimer's disease as it progresses

September 18, 2013
What if doctors could visualize all of the processes that take place in the brain during the development and progression of Alzheimer's disease? Such a window would provide a powerful aid for diagnosing the condition, monitoring ...

Study examines association between small-vessel disease, Alzheimer pathology

May 12, 2014
Cerebral small-vessel disease (SVD) and Alzheimer disease (AD) pathology appear to be associated.

Researchers identify new group of proteins in the brains of Alzheimer's patients

June 13, 2012
Researchers from Boston University School of Medicine (BUSM) have identified a novel group of proteins that accumulate in the brains of patients with Alzheimer's disease. These findings, which appear online in the Journal ...

Recommended for you

Rocky start for Alzheimer's drug research in 2018

January 19, 2018
The year 2018, barely underway, has already dealt a series of disheartening blows to the quest for an Alzheimer's cure.

Alzheimer's disease: Neuronal loss very limited

January 17, 2018
Frequently encountered in the elderly, Alzheimer's is considered a neurodegenerative disease, which means that it is accompanied by a significant, progressive loss of neurons and their nerve endings, or synapses. A joint ...

Anxiety: An early indicator of Alzheimer's disease?

January 12, 2018
A new study suggests an association between elevated amyloid beta levels and the worsening of anxiety symptoms. The findings support the hypothesis that neuropsychiatric symptoms could represent the early manifestation of ...

One of the most promising drugs for Alzheimer's disease fails in clinical trials

January 11, 2018
To the roughly 400 clinical trials that have tested some experimental treatment for Alzheimer's disease and come up short, we can now add three more.

Different disease types associated with distinct amyloid-beta prion strains found in Alzheimer's patients

January 9, 2018
An international team of researchers has found different disease type associations with distinct amyloid-beta prion strains in the brains of dead Alzheimer's patients. In their paper published in Proceedings of the National ...

Advances in brain imaging settle debate over spread of key protein in Alzheimer's

January 5, 2018
Recent advances in brain imaging have enabled scientists to show for the first time that a key protein which causes nerve cell death spreads throughout the brain in Alzheimer's disease - and hence that blocking its spread ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.