Researchers from University College London are working on a way in which eye tests could be used to diagnose Alzheimer's disease. The test works on the basis that the retina is an extension of the brain and involves a chemical marker being either injected into the arm or administered via eye drops. Once the substance is in the body it highlights dying nerve cells which can then be seen with an infrared camera. Anything more than 20 damaged cells could indicate the onset of Alzheimer's disease and once diagnosed treatment could start immediately.
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