Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Automated analysis of MR images may identify early Alzheimer’s disease

26.05.2009
Analyzing MRI studies of the brain with software developed at the Martinos Center for Biomedical Imaging at Massachusetts General Hospital (MGH) may allow diagnosis of Alzheimer's disease and of mild cognitive impairment, a lesser form of dementia that precedes the development of Alzheimer's by several years.

In their report that will appear in the journal Brain and has been released online, the MGH/Martinos team show how their software program can accurately differentiate patients with mild cognitive impairment or Alzheimer's disease from normal elderly individuals based on anatomic differences in brain structures known to be affected by the disease.

"Traditionally Alzheimer's has been diagnosed based on a combination of factors – such as a neurologic exam, detailed medical history and written tests of cognitive functioning – with neuroimaging used primarily to rule out other diseases such as stroke or a brain tumor," says Rahul Desikan MD, PhD, of the Martinos Center and Boston University School of Medicine, lead author of the Brain paper. "Our findings show the feasibility and importance of using automated, MRI-based neuroanatomic measures as a diagnostic marker for Alzheimer's disease."

The researchers note that mild cognitive impairment occurs in about 20 percent of elderly individuals – as many as 40 percent of those over 85 – 80 percent of whom develop Alzheimer's within five or six years. Since drugs that may slow the progression of Alzheimer's are in development, the ability to treat patients in the earliest stages of the disease may significantly delay progression to dementia. To investigate whether MR imaging can produce diagnostic markers for mild cognitive impairment and Alzheimer's disease, the research team used FreeSurfer – an openly available imaging software package developed at the Martinos Center and the University of California at San Diego – to examine a number of neuroanatomic regions across a range of normal individuals and patients with mild cognitive impairment and Alzheimer's disease.

In the first phase of the study, the investigators examined MR images of 97 elderly individuals, some who had been determined to have mild cognitive impairment and others who were cognitively normal. Analyzing those images identified three regions of the brain where structural differences distinguished the normal controls from participants with mild cognitive impairment with an accuracy of 91 percent. Earlier pathological and imaging studies have found evidence of early Alzheimer's disease in these three areas – the hippocampus, entorhinal cortex and the supramarginal gyrus.

To validate the accuracy and assess the reliability of the first-phase observations, the investigators analyzed imaging data from 216 individuals in the Alzheimer's Disease Neuroimaging Database – 94 of whom were normal, 58 who had mild cognitive impairment at the time of imaging and went on to develop dementia, and 65 who had probable Alzheimer's based on their clinical symptoms. These participants also had a series of neuropsychological tests, and samples of cerebrospinal fluid were available for many of them.

Automated MRI measures of the same three areas identified in the first phase – entorhinal cortex, hippocampus, and supramarginal gyrus – discriminated individuals with mild cognitive impairment from normal elderly controls with 95 percent accuracy, and patients with Alzheimer's were discriminated from normal controls with 100 percent accuracy. The MRI measures also were significantly correlated with clinical and cognitive tests of dementia, particularly memory decline, and with biomarkers of cellular pathology such as the Alzheimer's-associated forms of the tau and amyloid proteins.

"Our results indicate that these automated MRI measures are one effective way of identifying individuals in the earliest stages of Alzheimer's disease, but before this technology can be used clinically, several follow-up studies need to be done," says Desikan. "Those include determining whether these automated MRI measures can accurately predict which individuals with mild cognitive impairment will progress to Alzheimer's; seeing if they can differentiate Alzheimer's from other neurodegenerative diseases; assessing how these measures do at early diagnosis, compared to other measures such as cellular biomarkers; and then validating all of these findings against the gold standard for diagnosis, postmortem examination of brain tissue."

Bruce Fischl, PhD, of the Martinos Center is the senior author of the Brain study. Additional co-authors are Nicholas Schmansky, Douglas Greve and David Salat of the Martinos Center; Howard Cabral, Boston University School of Public Health; Christopher Hess, William Dillon, Christine Glastonbury and Michael Weiner, University of California, San Francisco; and Randy Buckner, Harvard University and Howard Hughes Medical Institute. Support for the study came from the American Federation for Aging Research, the National Center for Research Resources, the National Institute for Biomedical Imaging and Bioengineering, the Mental Illness and Neuroscience Discovery Institute, the National Institute on Aging, the National Institute for Neurologic Disorders and Stroke and several other organizations.

Massachusetts General Hospital, established in 1811, is the original and largest teaching hospital of Harvard Medical School. The MGH conducts the largest hospital-based research program in the United States, with an annual research budget of more than $500 million and major research centers in AIDS, cardiovascular research, cancer, computational and integrative biology, cutaneous biology, human genetics, medical imaging, neurodegenerative disorders, regenerative medicine, systems biology, transplantation biology and photomedicine.

Sue McGreevey | EurekAlert!
Further information:
http://www.mgh.harvard.edu

More articles from Medical Engineering:

nachricht Novel breast tomosynthesis technique reduces screening recall rate
21.02.2017 | Radiological Society of North America

nachricht Biocompatible 3-D tracking system has potential to improve robot-assisted surgery
17.02.2017 | Children's National Health System

All articles from Medical Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Microhotplates for a smart gas sensor

22.02.2017 | Power and Electrical Engineering

Scientists unlock ability to generate new sensory hair cells

22.02.2017 | Life Sciences

Prediction: More gas-giants will be found orbiting Sun-like stars

22.02.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>