What is Retina?
The retina is an extremely thin-layered tissue that is positioned at inner back surface of eye. The image is formed onto retina by focusing of light by both lens and cornea. This light which strikes the retina causes a flow of electrical and chemical signals that eventually activate nerve impulses and as a result of this, generates an electrical retort in other layers of retina. These electrical signals are then sent to various visual centers of brain through fibers of optic nerves. When these electric signals enter in specific areas of our brain, it allows us to see and also to understand what we are seeing. The size of retina is about a postage stamp.
Retina comprises of a layered structure that has several layers of neurons which are interconnected by synapses. Macula is the central part of retina. There are two types of light receptor cells located within retina which are known as cones and rods. Rods permit us to see in situation of compact illumination. Cones supply us with color and sharpness of vision.
There are several types of Retinal Diseases:
•Age Related Macular Degeneration (ARMD)
•Retinopathy of prematurity