Neurodegeneration, or the dysfunction and eventual death of brain cells, can lead to many symptoms – most prominently associated with dementia. Improper blood supply to the brain, often resulting from issues with local blood vessels, can lead to similar impacts. Both these phenomena can lead to the erosion of the brain.
Neuroimaging is one of the key ways to study the structure and the function of the brain in a non-invasive way.
There are many ways to try to gauge what is going on in the brain during a person’s lifetime, but neuro (brain) imaging allows clinicians and researchers to actually see the physical manifestations of neurodegeneration and cerebrovascular damage to the brain.
ONDRI’s neuroimaging contribution to science
Working with the Ontario Brain Institute, ONDRI has released significant dementia-related data from its Foundational Study (2014-18). These data, delivered through the Brain-CODE neuroinformatics platform, include de-identified neuroimages and, importantly, associated volumetric data, along with other measures.
Volumetric data provide objective measures of the size of the brain. To a trained professional, these measures can be compared to ‘normal’ volumetric measures to help determine the degree of neurodegeneration or cerebrovascular effects that the brain has suffered.
The release of volumetric data following a research study is not the norm. This feat required significant planning, preparation, and detailed analytical work.
Volumetric data allows for cross-platform analysis
Volumetric brain measures are a way to deliver important quantitative information to an audience of scientists who have other related expertise but are not experts in neuroimaging. This allows for these neuroimaging data to be used to verify or substantiate observations in other fields or platforms, in a highly effective and efficient way.
This facet of ONDRI’s data release highlights the strength of the ONDRI initiative overall, i.e., the incredible ability of this cross-disease, cross-platform dataset to facilitate new important discoveries in this complex area of study.
Quantifying inherent distortions
A related aspect worth mentioning is the work ONDRI researchers completed to quantify the effect of gradient distortions on their images. This detailed analysis allowed researchers to appreciate the scale of such distortions and assess their potential impact on comparisons of specific brain volumes between different participant groups.
“Our ONDRI neuroimaging data are world class with respect to the methods and standards that were used to gather them, along with their cleanliness and precision”, said Robert Bartha PhD, a Scientist in the imaging research group at the Robarts Research Institute at Western University, and Lead of ONDRI’s Neuroimaging Platform.
Scientists working as part of the neuroimaging platform worked so effectively to ensure these data were of the highest quality, that they have been able to conduct unique studies that require a high level of alignment between different imaging contrasts – like exploring how areas of the brain are functionally and structurally connected.
Potential neuroimaging breakthroughs
One of the ways ONDRI’s neuroimaging data are currently being used is through studying resting state functional MRI for brain image mapping.
Resting state data through ONDRI’s research were acquired over 10 minutes – with participants lying in a relaxed state as their brain was imaged. Scientists then examined these data, looking for how signals fluctuate, and brain activity levels differ in different parts of the brain, over this period.
This analysis has led to the development of brain maps that help to illuminate how different parts of the brain communicate with each other.
If the images are of high quality and comparable, as they are with ONDRI, researchers can use these data to differentiate between people living with conditions such as mild cognitive impairment, and those with other disorders, or even with no related disorders.
This work will potentially lead to significant breakthroughs in diagnostic capability for the future, dovetailing on the many breakthroughs achieved through ONDRI to date.
Images leading to correction of misdiagnoses
ONDRI studied five diseases that can cause dementia, utilizing the same protocols, including a common neuroimaging protocol. This unique methodology, which also included the standardization of images received from different scanners at different labs, allowed researchers the opportunity to verify diagnoses; the methodology even allowed researchers, in some cases, to reclassify participants as having a different diagnosis than they came into the study with.
“ONDRI’s Foundational Study represented the ‘Cadillac’ of functional MRI protocols”, said Joel Ramirez PhD, Research Associate at Sunnybrook Research Institute and ONDRI researcher.
“The resulting high quality data have allowed us to make discoveries that would not have been possible otherwise; discoveries such as the NOTCH3 variant and its potential association with Parkinson Disease, for example. Most important, many of ONDRI’s studies that started in other platforms have then accessed the neuroimaging data to verify their findings visually”, Ramirez continued.
To date ONDRI researchers have published many important studies emanating from the neuroimaging platform, with more important contributions to come.
“Ultimately, we would like qualified individuals to be able to look at an image of the brain to understand what is going on from a biological point of view, and furthermore, to use this image as a reliable indicator of what will happen in the future. This would allow people time to plan for quality-of-life improvements and interventions,” said Bartha.
ONDRI is proud to have released baseline data from its Foundational Study through the Ontario Brain Institute’s Brain-CODE platform.