Speaker
Description
Introduction: We have previously demonstrated ex vivo, dye-free imaging of retinal protein deposits in the human retina which predict the presence of deposits in the brain of: 1) amyloid beta in association with Alzheimer’s disease (AD), 2) alpha synuclein in association with Dementia with Lewy Bodies (DLB) and Multiple System Atrophy (MSA) and 3) TDP-43 in association with ALS and FTLD-TDP. Postmortem, the number of deposits found in retinas with an associated brain pathology of AD predicted severity of the disease. In AD, retinal and brain deposits are found years before diagnosis. Here, we use polarized light to image protein deposits in the retina of the living eye.
Methods: A custom module was added to the front of a commercial retinal imaging system, which produced circularly polarized light incident on the eye. Light reflected from the retina exited the eye, was incident on the quarter wave plate followed by a linear polarizer and was recorded at 30 frames/sec. The individuals imaged included 1 with a diagnosis of AD, 1 over 65 with a family history of AD, 1 diagnosed with age related macular degeneration (AMD) and 1 who had no history of AD or AMD.
Results: In the individuals with either a family history of the disease or a diagnosis of AD, deposits, consistent with Alzheimer’s disease (and similar to those imaged ex vivo), were imaged in the anterior (neural) layers of the retina. One had numerous deposits and one had sparse deposits consistent with early Alzheimer’s disease pathology. Three individuals had deposits located in the more posterior layers of the retina, consistent with AMD.
Conclusion: This Imaging method would be the only dye-free, non-invasive, inexpensive and widely available diagnostic of pathology due to Alzheimer’s and other neurodegenerative diseases. It could facilitate early interventions known to slow diseases progression.
| Keyword-1 | Retina |
|---|---|
| Keyword-2 | Alzheimer's |
| Keyword-3 | Biomarker |