Phase contrast imaging to detect transparent cells in the retinal ganglion cells layer

The eye is an optical window giving access to neural networks in a non-invasive way. It is possible to find in the retina biomarkers informing about the pathological state of other parts of the human body, and in particular of the brain. Neurodegenerative diseases could thus be diagnosed early and monitored by high-resolution imaging of the retina. However, a large part of the neurons in the retina are too transparent to be detected by existing techniques. At the Quinze-Vingts hospital, we have a unique retinal imaging platform in which ophthalmologists, neurologists and engineers participate. We implemented a technique based on scanning laser ophthalmoscopy (SLO) to capture the fine variations in refractive index between retinal cells. In this project we aimed at imaging and monitor cellular changes on transparent cells in the retinal ganglion cells layer in vivo on healthy participants and patients with neurodegenerative diseases