WINDOW TO THE BRAIN: USING RETINAL BIOMARKERS TO DIAGNOSE ALZHEIMER'S DISE

Three biomarkers were identified to detect Alzheimer’s disease in the retina of the eye: thinning of the retinal nerve fiber layer, thickening of the choroid, and thinning of a retinal vein. To enable off-site analysis of retinal biomarkers in optical coherence tomography (OCT) scans, software was developed that is as accurate as the commercial Heidelberg Eye Explorer software that is available only with onsite scanning equipment (r2 = 0.999). A total of 163 eye scans were analyzed with the software. Results showed that the retinal nerve fiber layer was significantly thinner (p = 0.0004), the choroid was significantly thicker (p = 0.0171), and retinal vein diameter was significantly smaller (p < 0.0001) in the Alzheimer’s group than in the control group. An online statistical confidence interval calculator was used to establish normal ranges for each retinal biomarker, against which retinal biomarkers were compared to predict Alzheimer’s disease, and the normal ranges were coded into the software. The software showed 97% accuracy in identifying patients who have diagnoses of Alzheimer’s disease in their medical records. Finally, code was added to enable ophthalmologists and/or ophthalmology technicians to use the software to evaluate OCT retinal scans.