Vision Screening for Alzheimer's Disease: Prevention from an Ophthalmologist's Perspective (There is More to Vision than Meets the Eye).

Recent evidence suggests that memory impairment and vision impairment are closely linked in Alzheimer's disease and that special testing for vision impairment can improve early detection and treatment of dementia. Visual images, attention, memory, awareness, and salience are tightly bound together in the cerebral cortex; under normal circumstances, these functions perform seamlessly to produce a visual reality of the external world. Alzheimer's disease-now considered a chronic illness-unravels the fabric of reality woven together over a lifetime of experience: The disease produces disconnected threads of visual perception, memory, and cognition. The earliest neuroanatomic manifestations of this process begin in the limbic system and medial temporal lobe of the brain, areas critical for detailed visual perception and memory management. Thus, by using vision tests to detect impaired image formation and memory, vision care specialists can play a valuable role in secondary and tertiary prevention, as well as in early treatment of eye disease and dementia. In addition to reducing health care utilization, prevention can be expected to improve functioning and health-related quality of life.