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Dementia tracked using healthy-brain MRIs

Researchers have determined a method to predict the progression of dementias using MRIs of healthy brains, according to recent study results.

Researchers used MRIs of 14 healthy brains to create models that accurately represented the spread of dementia along neuronal pathways. The models closely matched actual MRIs of 36 patients with dementia — 18 with Alzheimer’s disease and 18 with frontotemporal dementia.

The models revealed that various forms of dementia spread along vulnerable fiber pathways in the brain, and not by proximity, researchers wrote. That kind of progression, they added, is similar to prion disease. Results show that brain damage occurs through “prion-like” transsynaptic transmission of disease agents such as the beta-amyloid and tau proteins, which are “misfolded” and then replicated.

Michael Weiner, MD, one of the study’s researchers and a UCSF professor of medicine, radiology and psychiatry, emphasized in a press release the similarity between prion disease and dementia. “The idea of a prion-like mode of progression in dementias, which many scientists are beginning to support, is that the misfolded protein in one neuron will infect a neighboring brain cell, causing proteins in that cell to misfold in turn, and that the spread of these misfolded proteins flows along certain networks in the brain,” he said. “For instance, in Alzheimer’s, there is a spread of amyloid protein along the memory network. This paper reinforces the idea that the damage occurs progressively along that network and others.”

According to the researchers, there are an estimated 25 million people worldwide affected by dementia. The modeling techniques featured in the study can be used for differential diagnosis and “especially prediction of future atrophy using baseline MRI morphometrics,” they wrote.

Disclosure: The researchers report no relevant financial disclosures.