Understanding the Functions and Parts of the Cornea of the Eye

The cornea is the outer layer of the eye in the form of a dome-shaped membrane, which covers the front of the eye. The role of the cornea is very important for vision. Each part of the cornea of the eye has their respective functions, but they support one another. Unlike other body tissues, the cornea does not have blood vessels. The function of blood vessels in the cornea is replaced by tears and aqueous humor (slimy clear liquid in the eyes). Cornea is a sensitive or excitatory tissue, because it belongs to the part of the body that is passed through the most nerve tissue.

Get to know the Corneal Function and its various parts

The main function of the cornea is to refract (bend) and focus the light entering the eye. In the process of seeing, the incoming light needs to be refracted by the cornea into the lens of the eye, then forwarded to the retina. In the retina, light is converted into electrical impulses to be transmitted to the brain, then translated into images. When the eye is likened to a camera, the cornea is part of the camera lens. The cornea also has other functions, namely protecting the eye from foreign particles (germs or dirt) and exposure to ultraviolet rays that can harm the eye. To perform these functions, the cornea has five parts, namely:

1. Epithelial tissue

Epithelial tissue is the outer layer of the cornea that serves to protect the eye from foreign particles, such as dust, water, or bacteria. The sclera or the whites of the eyes help 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 when the eyes are scratched or rubbed too hard. These nerve endings also help the corneal reflex, or better known as the blink reflex, when the eye is exposed to a foreign object.

2. Bowman Layer

After epithelial tissue, there is a transparent membrane made of collagen. This membrane is called the Bowman layer and serves to maintain the shape of the cornea. This layer has no regenerative ability, so injury to this area will cause permanent scarring or scarring. If the scar is large enough, your vision may be disturbed.

3. Stroma

The stroma is the thickest layer of the cornea which is just behind the Bowman layer. This layer is composed of water and collagen and is an area of ​​refraction of light in the cornea. Therefore, it is important to keep the stroma transparent and translucent. In addition, the stroma also serves to maintain the shape of the cornea to remain elastic, dense, and strong.

4. Descemet membrane

Descemet membrane is the thinnest and strongest tissue in the cornea. This membrane is made of collagen and serves as a place for endothelial cells to rest while protecting them from infection and injury. Descemet membrane has a good self-recovery ability, so it is easy to heal after an injury.

5. Endothelial layer

The endothelial layer is a single, thin layer that lies in the deepest part of the cornea and is in direct contact with the aqueous humor. This layer serves to keep the cornea clear and regulates the water content 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 there is no visual impairment due to corneal disease. If complaints arise in the eye, such as the eyes continue to runny, reddish, too sensitive to light, and cloudy or blurred vision, you should immediately consult an ophthalmologist to be treated properly.