Non invasive in vivo hyperspectral imaging of the retina for potential biomarker use in Alzheimer's disease
Studies of rodent models of Alzheimer's disease (AD) and of human tissues suggest that the retinal changes that occur in AD, including the accumulation of amyloid beta (Ab) may serve as surrogate markers of brain Ab levels. As Ab has a wavelength dependent effect on light scatter, we investigate the potential for in vivo retinal hyperspectral imaging to serve as a biomarker of brain Ab. Significant differences in the retinal reflectance spectra are found between individuals with high Ab burden on brain PET imaging and mild cognitive impairment (n 15) and age matched PET negative controls (n 20) Retinal imaging scores are correlated with brain Ab loads. The findings are validated in an independent cohort, using a second hyperspectral camera. A similar spectral difference is found between control and 5xFAD transgenic mice that accumulate Ab in the brain and retina. These findings indicate that retinal hyperspectral imaging may predict brain Ab load. The use of PET for detection of Ab in the brain in AD has limitations; studies also indicate that retinal changes, including Ab deposition, occur in AD. Here the authors demonstrate the potential to use in vivo retinal hyperspectral imaging as a surrogate for brain accumulation of Ab.
Nature Communications