Washington, July 12 : Canadian scientists have unearthed clear evidence that increases in the size of the ventricles, fluid-filled cavities in the brain, are directly linked with cognitive impairment and Alzheimer's disease. Robert Bartha and his colleagues at Robarts Research Institute at The University of Western Ontario have found that the volume of the brain ventricles expands as surrounding tissue dies.
Writing about their findings in the journal Brian, the researchers say that ventricle size increases with mild cognitive impairment before a diagnosis of Alzheimer's disease, and continues to increase with the onset and progression of Alzheimer's disease after only six months.
"These findings mean that, in the future, by using magnetic resonance imaging (MRI) to measure changes in brain ventricle size, we may be able to provide earlier and more definitive diagnosis," said Bartha, who is also an Associate Professor in the Schulich School of Medicine and Dentistry in Medical Biophysics.
"In addition, as new treatments for Alzheimer's are developed, the measurement of brain ventricle changes can also be used to quickly determine the effectiveness of the treatment," the researcher added. According to the researchers, their study also revealed that Alzheimer's patients with a genetic marker for Alzheimer's disease exhibited faster expansion in ventricle volume. The researchers used MRI scans from individuals from across North America for their study, and examined 500 data sets of individuals at baseline and six months later.
The images were obtained from the Alzheimer's Disease Neuroimaging Initiative (ADNI), a large multi-site trial sponsored by the National Institutes of Health in the United States and the pharmaceutical industry.
The images included MRIs of individuals with no cognitive impairment, those with mild cognitive impairment, and people with Alzheimer's disease.
The researchers examined the MRIs using software developed by Cedara Software, the OEM division of Merge Healthcare, which enabled them to process large volumes of data very quickly.
"This is one of the first major research studies published using data from ADNI, but there will be many more neuroimaging and biomarker discoveries to arise from the ADNI project. It is a tremendous opportunity for researchers anywhere in the world to use the ADNI databases, to collaborate and share their findings in a new way that will move Alzheimer's disease research forward more quickly, objectively and effectively. Already we are building new international collaborations, arising from ADNI, that we could not have even imagined," said Dr. Michael Borrie, a co-investigator on the research.