timesofummah.com – Understanding the Functions and Parts of the Cornea of the Eye. Cornea is the outermost layer of the eye in the form of a dome-shaped clear membrane, which covers the front of the eye. The role of the cornea is very important for vision. Each part of the eye’s cornea has its own function, but supports each other.
Unlike other body tissues, the cornea has no blood vessels. The function of blood vessels in the cornea is replaced by tears and aqueous humor (clear mucus in the eye). The cornea is a sensitive or sensitive tissue, because it is the part of the body that has the most nerve tissue.
Know the Function of the Cornea and Its Various Parts
The main function of the cornea is to refract (bend) and focus the light that enters the eye. In the process of seeing, incoming light needs to be refracted by the cornea towards the eye lens, then forwarded to the retina.
In the retina, light is converted into electrical impulses to be passed on to the brain, then translated into images. If the eye is likened to a camera, then the cornea is part of the camera lens.
The cornea also has another function, which is to protect the eye from foreign particles (germs or dirt) and exposure to ultraviolet light which can harm the eye.
To perform these various functions, the cornea has five parts, namely:
1. Epithelial tissue
Epithelial tissue is the outermost layer of the cornea which functions to protect the eye from foreign particles, such as dust, water or bacteria. The sclera or the white part of the eye also helps this function. Epithelial tissue is also a soft textured surface, similar to gelatin, which can absorb oxygen and nutrients from tears to the cornea.
In this network, there are thousands of nerve endings. Therefore, you can feel pain if your eyes are scratched or rubbed too hard. These nerve endings also help in the occurrence of the corneal reflex, or better known as the blink reflex, when the eye is hit by a foreign object.
2. Bowman layer
After the epithelial tissue, there is a transparent membrane made of collagen. This membrane is called Bowman’s layer and functions to maintain the shape of the cornea.
This layer has no regenerative (self-renewing) ability, so injury to this area will result in a permanent scar or scar tissue. If the scar is large enough, your vision may be disturbed.
The stroma is the thickest layer of the cornea, immediately behind Bowman’s layer. This layer is composed of water and collagen and is the area of light refraction on the cornea. Therefore, it is important to keep the stroma transparent and translucent.
In addition, the stroma also functions to maintain the shape of the cornea so that it remains elastic, dense and strong.
4. Descemet’s membrane
Descemet’s membrane is the thinnest and strongest tissue in the cornea. This membrane is made of collagen and serves as a resting place for endothelial cells while protecting them from infection and injury.
Descemet’s membrane has good self-healing ability, so it heals easily after injury.
5. Endothelial layer
The endothelial layer is a single, thin layer that lies in the innermost part of the cornea and is in direct contact with the aqueous humor. This layer functions to keep the cornea clear and regulate water levels in the eye, by absorbing water from the stroma.
Cornea is a very important part of the eye. Therefore, the health of the cornea needs to be maintained properly, so that vision problems do not occur due to diseases of the cornea. If the cornea is affected by certain diseases, for example a corneal abrasion or infection, then this condition can cause the eye to experience vision problems.