Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Imaging shows brain connection breakdown in early Alzheimer's disease

01.12.2014

Changes in brain connections visible on MRI could represent an imaging biomarker of Alzheimer's disease, according to a new study presented today at the annual meeting of the Radiological Society of North America (RSNA).

Alzheimer's disease is the most common form of dementia. As many as 5 million Americans are affected, a number expected to grow to 14 million by 2050, according to the Centers for Disease Control and Prevention.


Structural connectomes (top two rows) and corresponding florbetapir PET images (bottom two rows) in four patients with normal cognition (NC) with the lowest whole cortex amyloid burden (left) and the four patients with AD with the highest whole cortex amyloid burden (right) focused on the composite regions used in connectome versus amyloid analysis. Nodes represent the centroids of the FreeSurfer parcellations in the frontal (red), cingulate (green), temporal (light blue), and parietal (dark blue) regions. This is merely a schematic intended to show the concepts and is not intended to show any visually discernible generalizable difference between the patients with NC and those with AD. Structural network metrics provide more sensitive information about the connectome than are apparent through visualization alone.

Credit: RSNA

Preventive treatments may be most effective before Alzheimer's disease is diagnosed, such as when a person is suffering from mild cognitive impairment (MCI), a decline in cognitive skills that is noticeable but not severe enough to affect independent function. Previous efforts at early detection have focused on beta amyloid, a protein found in abnormally high amounts in the brains of people with Alzheimer's disease.

For the new study, researchers looked at the brain's structural connectome, a map of white matter tracts that carry signals between different areas of the brain.

"The structural connectome provides us with a way to characterize and measure these connections and how they change through disease or age," said study co-author Jeffrey W. Prescott, M.D., Ph.D., radiology resident at Duke University Medical Center in Durham, N.C.

Dr. Prescott and colleagues analyzed results from 102 patients enrolled in a national study called the Alzheimer's Disease Neuroimaging Initiative (ADNI) 2. The patients had undergone diffusion tensor imaging (DTI), an MRI method that assesses the integrity of white matter tracts in the brain by measuring how easy it is for water to move along them.

"It is known that water prefers moving along the defined physical connections between regions in the brain, which makes DTI a great tool for evaluating the structural connectome," Dr. Prescott said.

The researchers correlated changes in the structural connectome with results from florbetapir positron emission tomography (PET) imaging, a technique that measures the amount of beta amyloid plaque in the brain. Increased florbetapir uptake corresponds with greater amounts of the protein.

The results showed a strong association between florbetapir uptake and decreases in strength of the structural connectome in each of the five areas of the brain studied.

"This study ties together two of the major changes in the Alzheimer's brain--structural tissue changes and pathological amyloid plaque deposition--and suggests a promising role for DTI as a possible diagnostic adjunct," Dr. Prescott said.

Based on these findings, DTI may offer a role in assessing brain damage in early Alzheimer's disease and monitoring the effect of new therapies.

"Traditionally, Alzheimer's disease is believed to exert its effects on thinking via damage to the brain's gray matter, where most of the nerve cells are concentrated," said Jeffrey R. Petrella, M.D., professor of radiology at Duke and senior author on the study. "This study suggests that amyloid deposition in the gray matter affects the associated white matter connections, which are essential for conducting messages across the billions of nerve cells in the brain, allowing for all aspects of mental function."

"We suspect that as amyloid plaque load in the gray matter increases, the brain's white matter starts to break down or malfunction and lose its ability to move water and neurochemicals efficiently," added Dr. Prescott.

The researchers plan to continue studying this cohort of patients over time to gain a better understanding of how the disease evolves in individual patients. They also intend to incorporate functional imaging into their research to learn about how the relationship between function and structure is affected with increasing amyloid burden.

Other co-authors on the study are P. Murali Doraiswamy, M.D., and Kingshuk R. Choudhury, Ph.D.

Note: Copies of RSNA 2014 news releases and electronic images will be available online at RSNA.org/press14 beginning Monday, Dec. 1.

RSNA is an association of more than 54,000 radiologists, radiation oncologists, medical physicists and related scientists, promoting excellence in patient care and health care delivery through education, research and technologic innovation. The Society is based in Oak Brook, Ill. (RSNA.org)

For patient-friendly information on MRI and PET, visit RadiologyInfo.org.

Linda Brooks | EurekAlert!

Further reports about: Disease PET RSNA Radiological Radiological Society beta breakdown cognitive nerve cells radiology role structural

More articles from Health and Medicine:

nachricht Cardiac diseases: when less is more
30.03.2017 | Universitätsspital Bern

nachricht TSRI researchers develop new method to 'fingerprint' HIV
29.03.2017 | Scripps Research Institute

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Researchers shoot for success with simulations of laser pulse-material interactions

29.03.2017 | Materials Sciences

Igniting a solar flare in the corona with lower-atmosphere kindling

29.03.2017 | Physics and Astronomy

As sea level rises, much of Honolulu and Waikiki vulnerable to groundwater inundation

29.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>