Abstract
Presentation Description :
The retina has been proposed as a window into the brain, and it may be affected in classic brain neurodegenerative pathologies like Parkinson disease (PD). Patients who suffer from PD also have visual impairments, and it is possible that retinal cellular and morphological changes could be used as biomarkers for PD. In the human PD retina, we have identified the same characteristic pathological features that are found in brain. The loss of retinal dopaminergic amacrine neurons and the impairment of their postsynaptic circuitries could explain the physiological visual symptoms. We describe accumulations of phosphorylated a-synuclein in ganglion cells and the presence of Lewy bodies, that correlate with brain neuropathology. In addition, there is a loss of ganglion and amacrine cells, and an inflammatory reaction mediated by microglia activation and Müller cells gliosis. Melanopsin retinal ganglion cells are also impaired, what may explain circadian dysfunctions and sleep disorders reported in PD patients. Some of these retinal cellular alterations may be observed in vivo, by OCT, fundus or pupillary reflex, and may act as early biomarkers of PD and help in disease diagnostic and treatment progression.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.