What Does cornea Mean
If we want to discover the meaning of the term cornea, it is inevitable that, in the first place, we know the etymological origin of that word. In this case, we can state that it comes from the medieval Latin word "cornea", which was a kind of tunic. A term this that, in turn, is related to the Latin noun “cornus”, which means “horn”.
In the field of anatomy , a membrane that is located in the anterior sector of the eyeball is called a cornea , through which the iris (the colored disc that, in its center, houses the pupil) is seen. It is a transparent and hard element.
The cornea is responsible for refracting light and gives the eye the ability to focus. It has a lens whose rear face is impregnated with aqueous humor (a liquid that oxygenates and nourishes the different structures of the eyeball), while its front face is in contact with a tear film that provides protection.
In the same way, we cannot ignore that another of the most important functions of the cornea is to act as a protective shield for the eye. Yes, because it takes care of dust or germs of all kinds. Specifically, this is a task that it also shares with tears, the eye socket, the eyelids and what is known as the sclera.
According to the species , the cornea has more or less layers. While dogs and cats, for example, have a four-layered cornea, the human cornea has six layers: corneal endothelium, Descemet's membrane, Dua's layer, corneal stroma, Bowman's stratum. and the corneal epithelium.
From these parts we can know data of interest such as these:
-The corneal endothelium, is made up of what are hexagonal cells and is responsible for hydrating the cornea to keep it transparent.
-Descemet's membrane, which has increased in thickness every ten years. It is made up of collagen fibers.
-The Dua layer, which is the last layer of the cornea.
-The corneal stroma, which is the thickest part.
-The Bowman stratum, which becomes thinner as human beings age.
-Corneal epithelium, which is formed by several layers of cells joined together.
The oxygen required by the cornea comes mostly from the aqueous humor. However, the membrane also receives oxygen from the air in the atmosphere, tears, and capillaries. Regarding nutrients, the cornea also receives them from aqueous humor, tears and capillaries.
Among the diseases that can affect the cornea are astigmatism , glaucoma , corneal dystrophy , megalocornea and keratitis . Depending on the type of disorder, treatment may require the use of contact lenses or refractive surgery.
Likewise, another series of problems, conditions or diseases that can affect the cornea are corneal erosions, ulcers, corneal opacity, allergies ...