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Retina, Vitreous and Uvea

Retina (rɛtini from Latin rēte meaning “net”) is a light-sensitive layer at the back of the eye that covers about 65 percent of its interior surface. It is the third and inner coat of the eye which is a light-sensitive layer of tissue. The optics of the eye create an image of the visual world on the retina (through the cornea and lens), which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical events that ultimately trigger nerve impulses. These are sent to various visual centres of the brain through the fibers of the optic nerve. The retina is a layered structure with several layers of neurons interconnected by synapses. The only neurons that are directly sensitive to light are the photoreceptor cells. These are mainly of two types: the rods and cones. Rods function mainly in dim light and provide black-and-white vision, while cones support daytime vision and the perception of colour.

The retina has ten distinct layers :-

Basement membrane elaborated by Müller cells (retinal cells).
Axons of the ganglion cell (neuron located in inner retina) nuclei (note that a thin layer of Müller cell footplates exists between this layer and the inner limiting membrane).
Contains nuclei of ganglion cells, the axons of which become the optic nerve fibres for messages and some displaced amacrine cells (interneurons in the retina).
Contains the synapse between the bipolar cell axons and the dendrites of the ganglion and amacrine cells.
Contains the nuclei and surrounding cell bodies (perikarya) of the amacrine cells, bipolar cells and horizontal cells.
Projections of rods and cones ending in the rod spherule and cone pedicle, respectively. These make synapses with dendrites of bipolar cells.[1] In the macular region, this is known as the Fiber layer of Henle.
Cell bodies of rods and cones
Layer that separates the inner segment portions of the photoreceptors from their cell nucleus
Layer of rod cells and cone cells
single layer of cuboidal cells (with extrusions not shown in diagram). This is closest to the choroid. These can be simplified into 4 main processing stages: photoreception, transmission to bipolar cells (exiss between photoreceptors, act to transmit signals from photoreceptors to ganglion cells), transmission to ganglion cells (neuron located near the inner surface) which also contain photoreceptors, the photosensitive ganglion cells (neuon located in retina), and transmission along the optic nerve. At each synaptic stage there are also laterally connecting horizontal (interconnecting neurons) and amacrine cells (interneurons in retina).