by John R. Fischer
, Senior Reporter | August 24, 2017
Noninvasive imaging could detect
early signs of Alzheimer's disease
The human eye may hold clues for determining the presence of early signs of Alzheimer’s disease.
That is, according to researchers at Cedars-Sinai Medical Center in California and NeuroVision Imaging LLC who have developed a new form of technology for detecting the presence of beta-amyloid protein deposits in the retina that reflect those found within the brain. Their findings were published as a study in JCI Insight
“We report here the development of an approach,” Dr. Maya Koronyo-Hamaoui, a research associate at Cedars-Sinai and a scientist and inventor at NeuroVision, and the senior leading author of the study, told HCB News. “It combines the use of a proprietary curcumin formulation with higher bioavailability than other curcumin products and the use of scanning laser ophthalmoscope-based ophthalmic devices that were modified to capture large peripheral retinal regions (wide angle of view) and filters for autofluorescence and curcumin fluorescence.”
The study is the first to use a retinal scan with high resolution to noninvasively image and calculate the number of retinal findings with a connection to beta-amyloid plaques in living humans.
Before tests were conducted on live humans, test subjects included live mice, as well as comparison of the retinas and brains of deceased patients, 23 with confirmed cases of Alzheimer’s and 14 without it. More than 16 live patients were examined using autofluorescence imaging to identify deposits of plaque. Before humans, trials were also conducted on mice.
Researchers reported a 4.7-fold increase in retinal plaque among Alzheimer’s patients, compared to healthy ones. In addition, it showed a correlation between retinal and brain plaques and within that, coexistence between the two. It is also the first analysis to show retinal plaque clusters, known as “hot spots”, which contain the most toxic forms of beta-amyloid with patterns in superior peripheral regions that were not studied before. The use of autoflorescence showed a 2.1-fold increase in rate.
The approach differs from PET scans and the study of cerebrospinal fluid for deposits, as these methods are invasive, expensive and impractical for routine screening and follow-up examinations.
Koronyo-Hamaoui says it could eventually be applied to address other conditions, following testing in those areas of study.
“Potentially yes," she said, “for the detection of other acute and chronic diseases associated with amyloid accumulation and/or, potentially, for other neurodegenerative diseases associated with other types of protein aggregation (when using other contrast agents). However, at this point, this is all theoretical and has not been tested yet.”
The approach has been submitted for FDA approval.