Here's how the Alzheimer's Association describes promising research that might offer an early diagnosis of Alzheimer's by detecting beta-amyloid protein plaques in the lens of the eye:
Building on their discovery that people with Alzheimer's have Beta-amyloid deposits that appear as unusual cataracts in the lens of the eye, Lee E. Goldstein, MD, PhD, of Brigham & Women's Hospital and Harvard Medical School [an accredited institution -ed.], Boston, and colleagues have developed a new, non-invasive, laser technology that may detect Alzheimer's at its earliest stages.
Clumps of abnormal Beta-amyloid protein (known as "plaques") accumulate outside the brain's nerve cells in people with Alzheimer's. As Goldstein and colleagues previously reported in the British medical journal The Lancet, these same Beta-amyloid clumps also collect in the lens of the eye as unusual "supranuclear cataracts." These Alzheimer's cataracts are different from common, age-related cataracts. This is the first evidence to date that Alzheimer's-related amyloid pathology may occur outside the brain.
In their most recent experiments to be reported in Madrid, the researchers used genetically engineered Alzheimer's mice to test a new, non-invasive molecular diagnostic technology. Goldstein and his team directed a brief pulse of infrared light - barely visible to humans - into the eye of each of four non-anesthetized Alzheimer mice and four age-matched normal mice every month starting at five months of age. Analysis of how the light bounced back from the lens completely separated the two types of mice by 10 months of age, when amyloid lesions were not detectable in the brain or eye by conventional means. The scientists believe that this technology, known as quasi-elastic light scattering (QLS), may detect the very earliest stages of Beta-amyloid pathology, even in eyes that are completely clear.
"Amyloid in the lens can be detected using extremely sensitive, non-invasive optical techniques. This makes the lens an ideal window for early detection and disease monitoring in Alzheimer's," Goldstein said.
