More than 5.3 million Americans have Alzheimer’s, and it’s the sixth-leading cause of death, according to the Alzheimer’s Association.One of the main hurdles in diagnosing Alzheimer’s is that it’s not easy or cheap to diagnose. The only definite way to diagnose the disease is with an autopsy. Short of that, brain scans, such as computed tomography (CT) or magnetic resonance imaging (MRI), can be performed.But an MRI costs $4,000, Dr. Trempe says. “Little progress will be made in the treatment of Alzheimer’s disease unless we find a readily available, easy, repeatable, non-invasive way to diagnose the disease early,” he says.To that end, optometrists can perform the comprehensive eye exam that they do every day using existing, readily available equipment to detect the ocular signs of Alzheimer’s early on in the disease process, Dr. Trempe says.“Optometrists are located in every part of the country. They see more than 50 million patients every year,” he says. “They are in an ideal position to detect the early signs of Alzheimer’s disease in the general population.”These early signs, or biomarkers, can be easily overlooked because the pathological findings associated with Alzheimer’s disease are similar to, and overlap with, the findings associated with common age-related eye diseases.These biomarkers include cortical cataract, retinal nerve fiber layer thinning and drusen. Source: Review of Optometry - February 2010.