Objective: Accumulating evidence suggests that the eye can be used in the assessment of
early on-set Alzheimer’s disease (AD). The eye offers a natural window to the brain through the retina.
The retina and brain share common developmental origins and patho-physiological origins and mechanisms,
having been sequestered from it during early development, but retaining its connections with
the brain via the optic nerve. Therefore, it is well understood that neurological abnormalities have a direct
profound impact on the retina. Recent studies suggest an array of physiological and pathological
changes in the retina in dementia and specifically in AD. There are also reports on imaging the two
hallmark proteins of the disease, extracellular amyloid beta peptides and intracellular hyper phosphorylated
tau protein, as a proxy to neuroimaging.
Results: In this review, we summarise retinal structural, functional and vascular changes reported to be
associated with AD. We also review techniques employed to image these two major hall mark proteins
of AD and their relevance for early detection of AD.