Retinal manifestations of Alzheimer's disease.

Alzheimer's disease (AD) is neurodegenerative condition and most common cause of dementia worldwide. Current criteria for its diagnosis and monitoring rely on subjective, expensive or invasive methods that lack sufficient sensitivity, such that a concrete diagnosis of AD can only be made postmortem. Given the structural similarities of the neuro-retina and central nervous system, researchers have shown many manifestations of AD to be detectible in the retinae of humans and transgenic models of AD. Due to the eye's unique optical properties allowing noninvasive in vivo imaging, the retina could provide a window for the early diagnosis and monitoring of AD long before symptom manifestation.