Purchase this article with an account.
Shaun Frost, Yogi Kanagasingam, Maya Koronyo-Hamaoui, Yosef Koronyo, David Biggs, Steven Verdooner, Ralph Martins; Retinal morphology in pre-clinical Alzheimer’s Disease. Invest. Ophthalmol. Vis. Sci. 2018;59(9):1123.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Brain imaging has revealed that amyloid beta-protein (AB) plaque pathology begins decades prior to diagnosis of Alzheimer’s disease (AD). Clinical trial results suggest that intervention in this pre-clinical phase will be required for disease modification, emphasizing the need for early detection. Our research has identified AB pathology, similar to that in the AD brain, but in the more accessible retina. Retinal morphology is being explored for non-invasive, early detection and monitoring of AD. In this study we utilise optical coherence tomography (OCT) to investigate whether retinal layer thickness is altered in clinical and pre-clinical AD, and how such changes relate to retinal and brain AB burden.
This report presents results from a trial of 192 participants from the Australian Imaging Biomarkers and Lifestyle (AIBL) study in Perth, Australia. The cohort included individuals with diagnosed AD (n=22), mild cognitive impairment (MCI, n=33) and healthy controls (HC, n=137). Participants underwent OCT imaging using a commercial device and automated software provided quantitative data on retinal layer thickness. OCT data was analysed with AIBL study data including clinical status, retinal AB burden, brain AB burden and cognitive test scores.
Significant thinning of retinal layers in the superior macula was observed in AD compared to HC (p < 0.05). Opposing this trend, increased thickness in the same region was associated with brain (p < 0.05) and retinal (p < 0.05) AB deposition in the HC group, suggesting that inflammation in this region may occur in pre-clinical AD. For the MCI subgroup with high brain AB burden, retinal thickness in the same region had a positive correlation with retinal AB burden (p < 0.05).
The results indicate that OCT can detect retinal changes in pre-clinical AD, and suggest that pre-clinical AD pathogenesis may involve inflammation in affected retinal regions, followed by thinning due to atrophy as the disease advances. Retinal imaging has potential for non-invasive, cost-effective screening for preclinical AD. A practical early detection test for AD would accelerate recruitment for therapeutic trials and provide the basis of a population screening test.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.
This PDF is available to Subscribers Only