Featured Research

from universities, journals, and other organizations

PET's Imaging Power May Be Best Indicator For Determining Which Patients Develop Alzheimer's

October 6, 2005
Society of Nuclear Medicine
Positron emission tomography (PET) imaging--with the radiotracer fluorodeoxyglucose (FDG)--is a promising tool in detecting Alzheimer's disease in patients who have mild cognitive impairment (MCI), according to a study reported in the October issue of the Society of Nuclear Medicine's Journal of Nuclear Medicine.

Related Articles

"PET imaging with FDG represents one of the mostpromising tools for diagnosis of Alzheimer's," said Alexander Drzezga,M.D., who is the senior physician with the department of nuclearmedicine at the Technical University of Munich in Germany. In fact,using PET imaging with FDG "may be the best indicator for determiningwhich MCI patients are most at risk of developing Alzheimer's," addedthe lead author of "Prediction of Individual Clinical Outcome in MildCognitive Impairment (MCI) by Means of Genetic Assessment and 18F-FDGPET."

Mild cognitive impairment (MCI) is a term used to describea subtle but measurable deterioration of cognitive capabilities, suchas memory function. Individuals with MCI are able to functionreasonably well in everyday activities, such as managing finances andpurchasing items at stores without assistance, but may have difficultyremembering details of conversations, events and upcoming appointments.

Patientswith MCI do not yet exhibit the criteria for the diagnosis of dementia,but the disorder is seen as a precursor to Alzheimer's disease, whichtakes years to develop in a person, said Drzezga. Many patients withMCI develop a progressive decline in their thinking abilities overtime, and Alzheimer's disease is usually the underlying cause.Alzheimer's is the most common form of dementia among older people; itis a progressive, irreversible brain disorder with no known cause orcure. More than 4.5 million Americans suffer from Alzheimer's and itssymptoms of memory loss, confusion, impaired judgment, personalitychanges, disorientation and loss of language skills.

"A highpercentage of MCI patients will develop Alzheimer's disease within ayear; however, some of these patients will never develop dementia andmay even improve with time," said Drzezga. Most MCI patients who showedabnormalities typical of Alzheimer's in their original PET scandeveloped dementia within 16 months, according to findings from the30-patient study. Most patients who did not show abnormalities in theiroriginal PET scan remained stable, he added.

Patients withAlzheimer's show characteristic changes of the cerebral glucosemetabolic pattern, with a decrease in affected brain regions, saidDrzezga. PET imaging with FDG allows the analysis of regional cerebralglucose metabolism. The study showed that "the assessment of cerebralglucose metabolism actually reflects ongoing pathological changesassociated with Alzheimer's disease on a molecular level and that themolecular imaging method PET is capable of depicting subtle changes inthe brain of MCI patients before a diagnosis of Alzheimer's based onneuropsychological evaluation is possible," said Drzezga.

Thestudy revealed that PET with FDG has a significantly higher accuracyfor detection of Alzheimer's than the genetic screening for theAPOEe4-risk factor. In addition, using both PET with FDG and theAPOEe4-genotype as genetic markers "allowed the definition of subgroupsof patients with very high risk and with very low risk," he added. Thisfinding could have implications for risk stratifying MCI patients intherapeutic trials, said Drzezga. "This study implies that PET—and inconsequence nuclear medicine—should continue to be strongly involved inthe challenging process of Alzheimer's research for early diagnosis aswell as for the development and evaluation of new treatment options,"he added.

Although there is currently no cure for Alzheimer's,new treatments are on the horizon as a result of accelerating insightinto the biology of the disease. "It is of increasing importance toidentify 'converters' at the earliest possible stage of disease todevelop and evaluate new and upcoming treatment options forAlzheimer's," added Drzezga, an SNM member.

PET is a safe,effective and painless biological imaging exam that "photographs" ordetects the presence and extent of neurological conditions. PET usesvery small amounts of radioactive materials that are targeted tospecific organs, bones or tissues. Radiotracers (such as FDG) areinjected and then detected by a special type of camera that works withcomputers to provide precise pictures of the area of the body beingimaged and molecular images of the body's biological functions. "Thecombination of molecular imaging with genotype assessment representsthe unique opportunity to interpret imaging findings in the context ofbackground information," explained Drzezga. "As we increase ourunderstanding of the human genome, individualized therapy andindividualized diagnosis will become increasingly important," he added."The current study underlines that a genetic disposition does notnecessarily represent a determined prognosis, thus, the need formeasures that allow the definition of the actual onset of a diseaseprocess is apparent. Molecular imaging could play an important role inthis context," he stated.

"Prediction of Individual Clinical Outcome in Mild Cognitive Impairment (MCI) by Means of Genetic Assessment and 18F-FDGPET" appears in the October issue of the Journal of Nuclear Medicine,which is published by the Society of Nuclear Medicine. Besides Drzezga,authors include Markus Schwaiger, M.D., department of nuclear medicine,Technical University of Munich, Germany; Timo Grimmer, M.D., MatthiasRiemenschneider, M.D., Panagiotis Alexopoulus, M.D., and AlexanderKurz, M.D., all with the department of psychiatry and psychotherapy,Technical University of Munich, Germany; Nicola Lautenschlager, M.D.,school of psychiatry and clinical neurosciences, University of WesternAustralia, Crawley, Australia; Hartwig Siebner, M.D., department ofneurology, Christian-Albrechts-University, Kiel, Germany, andNeuroImage-Nord, Hamburg, Germany; and Satoshi Minoshima, M.D., Ph.D.,department of radiology, University of Washington, Seattle.

Story Source:

The above story is based on materials provided by Society of Nuclear Medicine. Note: Materials may be edited for content and length.

Cite This Page:

Society of Nuclear Medicine. "PET's Imaging Power May Be Best Indicator For Determining Which Patients Develop Alzheimer's." ScienceDaily. ScienceDaily, 6 October 2005. <www.sciencedaily.com/releases/2005/10/051005231450.htm>.
Society of Nuclear Medicine. (2005, October 6). PET's Imaging Power May Be Best Indicator For Determining Which Patients Develop Alzheimer's. ScienceDaily. Retrieved November 29, 2014 from www.sciencedaily.com/releases/2005/10/051005231450.htm
Society of Nuclear Medicine. "PET's Imaging Power May Be Best Indicator For Determining Which Patients Develop Alzheimer's." ScienceDaily. www.sciencedaily.com/releases/2005/10/051005231450.htm (accessed November 29, 2014).

Share This

More From ScienceDaily

More Health & Medicine News

Saturday, November 29, 2014

Featured Research

from universities, journals, and other organizations

Featured Videos

from AP, Reuters, AFP, and other news services

Rural India's Low-Cost Sanitary Pad Revolution

Rural India's Low-Cost Sanitary Pad Revolution

AFP (Nov. 28, 2014) — One man hopes his invention -– a machine that produces cheap sanitary pads –- will help empower Indian women. Duration: 01:51 Video provided by AFP
Powered by NewsLook.com
Research on Bats Could Help Develop Drugs Against Ebola

Research on Bats Could Help Develop Drugs Against Ebola

AFP (Nov. 28, 2014) — In Africa's only biosafety level 4 laboratory, scientists have been carrying out experiments on bats to understand how virus like Ebola are being transmitted, and how some of them resist to it. Duration: 01:18 Video provided by AFP
Powered by NewsLook.com
WHO Says Male Ebola Survivors Should Abstain From Sex

WHO Says Male Ebola Survivors Should Abstain From Sex

Newsy (Nov. 28, 2014) — WHO cites four studies that say Ebola can still be detected in semen up to 82 days after the onset of symptoms. Video provided by Newsy
Powered by NewsLook.com
Ebola Leaves Orphans Alone in Sierra Leone

Ebola Leaves Orphans Alone in Sierra Leone

AFP (Nov. 27, 2014) — The Ebola epidemic sweeping Sierra Leone is having a profound effect on the country's children, many of whom have been left without any family members to support them. Duration: 01:02 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.


Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News


Free Subscriptions

Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile

Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?

Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins