Optometry and Vision Sciences - Research Publications

Permanent URI for this collection

http://hdl.handle.net/11343/312

Filters

2019 2
1 1
Reset filters

Settings
Statistics
Citations
Author: Bui, Bang × Author: Crowston, Jonathan × Author: Lim, Jeremiah × Author: Nguyen, Christine × Start date: 2009 ×

Search Results

Now showing 1 - 2 of 2
  • Item
    No Preview Available
    A retinal imaging biomarker of Alzheimer's disease
    van Wijngaarden, P ; Hadoux, X ; Hui, F ; Lim, J ; Nguyen, C ; Bui, B ; Crowston, J (Wiley, 2019-11-01)
    Background: Amyloid-beta (Ab) deposition in the brain is a diagnostic marker for Alzheimer's disease (AD), but current tests are costly and not widely available. Evidence from transgenic rodent models and post-mortem human tissues suggest that retinal accumulation of Ab may serve as a surrogate marker of brain Ab levels. As Ab has a wavelength-dependent effect on light scatter, we investigated the potential for in vivo retinal hyperspectral imaging to serve as a biomarker of brain Ab. Purpose: To develop and validate a retinal imaging biomarker of Alzheimer's disease. Methods: We performed human retinal hyperspectral imaging on individuals with high Ab burden on brain PET imaging and mild cognitive impairment (cases; n = 15), and age-matched PET-negative controls (n = 20). Image analysis methods were developed and validated on a second group of participants with and with (n = 4) and without (n = 13) moderate-to-high brain Ab burden and on transgenic mice (5xFAD) known to accumulate retinal Ab. Results: We show significant differences in retinal reflectance spectra between cases and controls in both cohorts (AUC ROC = 0.82, P = 0.001, 95% CI: 0.67-0.97). There was a moderate positive linear correlation between retinal imaging scores and brain Abburden (r = 0.46, 95%CI: 0.13-0.69, P = 0.008).The technique also enabled discrimination of AD-model mice from wild-type controls. Conclusion: We have developed a novel retinal imaging method to distinguish people with moderate-high brain Ab load from those without. This approach may have value for the diagnostic confirmation of AD.
  • Item
    Thumbnail Image
    Non-invasive in vivo hyperspectral imaging of the retina for potential biomarker use in Alzheimer's disease
    Hadoux, X ; Hui, F ; Lim, JKH ; Masters, CL ; Pebay, A ; Chevalier, S ; Ha, J ; Loi, S ; Fowler, CJ ; Rowe, C ; Villemagne, VL ; Taylor, EN ; Fluke, C ; Soucy, J-P ; Lesage, F ; Sylvestre, J-P ; Rosa-Neto, P ; Mathotaarachchi, S ; Gauthier, S ; Nasreddine, ZS ; Arbour, JD ; Rheaume, M-A ; Beaulieu, S ; Dirani, M ; Nguyen, CTO ; Bui, B ; Williamson, R ; Crowston, JG ; van Wijngaarden, P (NATURE PUBLISHING GROUP, 2019-09-17)
    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 (Aβ), may serve as surrogate markers of brain Aβ levels. As Aβ 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 Aβ. Significant differences in the retinal reflectance spectra are found between individuals with high Aβ 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 Aβ 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 Aβ in the brain and retina. These findings indicate that retinal hyperspectral imaging may predict brain Aβ load.