Featured Research

from universities, journals, and other organizations

PET Scan Distinguishes Alzheimer's From Other Dementia

Date:
November 1, 2007
Source:
University of Utah Health Sciences Center
Summary:
A PET scan that measures uptake of sugar in the brain significantly improves the accuracy of diagnosing a type of dementia often mistaken for Alzheimer's disease, a new study has found. The scan, FDG-PET, helped six doctors from three national Alzheimer's disease centers correctly diagnose frontotemporal dementia and Alzheimer's in almost 90 percent of cases.

A PET scan (positron emission tomography) that measures uptake of sugar in the brain significantly improves the accuracy of diagnosing a type of dementia often mistaken for Alzheimer's disease, a study led by a University of Utah dementia expert has found.

Related Articles


The scan, FDG-PET, helped six doctors from three national Alzheimer's disease centers correctly diagnose frontotemporal dementia (FTD) and Alzheimer's in almost 90 percent of cases in the study--an improvement of as much as 14 percent from usual clinical diagnostic methods. FDG stands for fluorodeoxyglucose, a short-lived radioactive form of sugar injected into people during PET scans to show activity levels in different parts of the brain. In Alzheimer's, low activity is mostly in the back part of the brain; in FTD, low activity is mostly in the front of the brain.

FDG-PET is an especially powerful tool in early treatment of FTD, said the study's lead author, Norman L. Foster, M.D., professor of neurology and director of the Center for Alzheimer's Care, Imaging and Research at the University of Utah School of Medicine.

FTD is a common cause of early onset dementia among people 45-64 years old and is marked by behavioral changes and language difficulties. Like Alzheimer's, it can take years to develop and, for now, is incurable. Although FTD is a separate disorder, it often meets clinical diagnostic criteria for Alzheimer's and often is misdiagnosed even by dementia experts.

"Early diagnosis of FTD can have a tremendous impact on the treatment for patients and their family members. Many patients are misdiagnosed and may be hospitalized and receive drugs for the wrong disease," Foster said. "Accurate diagnosis bypasses the costs, side-effects, and frustration of misguided care. Furthermore, one-third of FTD patients have a family history of a similar disorder and family members need to know if they are at increased risk of the disease."

"Dr. Foster's work involving patients from several NIA-sponsored Alzheimer's Disease Centers advances the use of PET imaging as a clinical tool," said Creighton Phelps, Ph.D., program director of the Alzheimer Disease Centers at the National Institute on Aging. "Combined with the patient's medical history and psychometric testing, it enhances a physician's ability to more accurately distinguish between FTD and early-onset AD."

As the U.S. population ages, the number of people with dementia is projected to increase markedly, with Utah and the Intermountain West expected to experience the fastest rate of growth. Although FDG-PET is widely available, it is not often used in dementia, because of insurance concerns. Medicare recently agreed to pay for FDG-PET scans to evaluate dementia, but currently many insurance companies in the Intermountain West and Utah do not. Foster is working to make FDG-PET scans available to those who need them and results of this study prove they sometimes are worth doing.

"This study shows FDG-PET is a reliable and valid diagnostic test that can aid physicians in making the sometimes difficult clinical distinction between AD (Alzheimer's disease) and FTD," Foster and his co-authors wrote. But PET scans alone are not enough to confirm FTD or Alzheimer's. "A careful consideration of the medical history and examination will continue to be essential to dementia evaluation."

Foster and his colleagues examined the medical records and FDG-PET scans of 45 patients who later had autopsies. Microscopic examination found 31 had Alzheimer's and 14 had FTD. The researchers summarized the clinical course of the disease in each patient. The expert neurologists at the NIH centers, who had 10 years to 25 years of experience, then were asked to decide what caused each patient's dementia using clinical information alone or using FDG-PET images.

The experts correctly distinguished FTD and Alzheimer's using only the clinical methods in 76 percent to 79 percent of the cases. Using the FDG-PET scans alone, however, the physicians correctly diagnosed the two dementias in 85 percent to 89 percent of cases. Adding FDG-PET to clinical information increased the correct diagnosis from 79 percent to 90 percent. The highest accuracy in diagnosis was achieved with SSP (stereotactic surface projection) displays, which summarize changes in brain activity and apply a statistical test to show significant areas of damage.

The PET scans also had other benefits. The researchers found in 42 percent of cases, the scans increased the experts' confidence in a correct diagnosis or made them question and sometimes change an incorrect diagnosis.

The study has appeared online in the journal Brain.

The study was funded by the National Institute on Aging, a part of the National Institutes of Health.


Story Source:

The above story is based on materials provided by University of Utah Health Sciences Center. Note: Materials may be edited for content and length.


Cite This Page:

University of Utah Health Sciences Center. "PET Scan Distinguishes Alzheimer's From Other Dementia." ScienceDaily. ScienceDaily, 1 November 2007. <www.sciencedaily.com/releases/2007/11/071101122822.htm>.
University of Utah Health Sciences Center. (2007, November 1). PET Scan Distinguishes Alzheimer's From Other Dementia. ScienceDaily. Retrieved December 20, 2014 from www.sciencedaily.com/releases/2007/11/071101122822.htm
University of Utah Health Sciences Center. "PET Scan Distinguishes Alzheimer's From Other Dementia." ScienceDaily. www.sciencedaily.com/releases/2007/11/071101122822.htm (accessed December 20, 2014).

Share This


More From ScienceDaily



More Mind & Brain News

Saturday, December 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Buzz60 (Dec. 19, 2014) A double-amputee makes history by becoming the first person to wear and operate two prosthetic arms using only his mind. Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com
Prenatal Exposure To Pollution Might Increase Autism Risk

Prenatal Exposure To Pollution Might Increase Autism Risk

Newsy (Dec. 18, 2014) Harvard researchers found children whose mothers were exposed to high pollution levels in the third trimester were twice as likely to develop autism. Video provided by Newsy
Powered by NewsLook.com
Yoga Could Be As Beneficial For The Heart As Walking, Biking

Yoga Could Be As Beneficial For The Heart As Walking, Biking

Newsy (Dec. 17, 2014) Yoga can help your weight, blood pressure, cholesterol and heart just as much as biking and walking does, a new study suggests. Video provided by Newsy
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.

Save/Print:
Share:

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



Save/Print:
Share:

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