banner

Cornea


data

The cornea is a transparent front part of the eye that covers the iris (colored part of the eye), pupil (opening at center of the eye), & anterior chamber (the fluid-filled inside of the eye). Collectively with the lens, cornea refracts light, roughly around 2/3rd of entire optical power of the eye.   In humans, the refractive power of cornea was around 43 dioptres. The cornea's core & major function is to refract, or bend, light. The cornea is mostly accountable to focus most of the light that enters the eye.
The cornea mainly composed of proteins & cells.
It does not consist of any kind of blood vessels, unlike most of the tissues in the human body. Blood vessels cloud the cornea will prevent from the refracting light adversely & properly, affect the vision.
Because there were no nutrient-supplying blood vessels in the cornea, tears & the aqueous humor (a watery fluid) in the anterior chamber will provide the cornea with the nutrients.

Corneal Layers: There are five major layers in cornea they are:

  • Corneal epithelium
  • Bowman's layer
  • Corneal stroma
  • Descemet's membrane
  • Corneal endothelium

The outer layer, is the epithelium, it is a layer of the cells which covers the cornea. It will absorb oxygen & nutrients from the tears & convey it to the rest of the cornea. It also contains some free nerve endings & also prevents from the foreign material which entering the eye.
Various refractive eye surgery procedures change the shape of the cornea to reduce the need for corrective lenses or otherwise improvement of the refractive state of eye.
 
The cornea tends to repair by itself swiftly from some minor abrasions. Deeper abrasions can also cause scars to form on cornea, which causes the cornea to lose its transparency; thereby it leads to visual impairment.

Authored by Dr.S Tony Fernandez

Ask doctor

Video Gallery

Testimonials

Call Us

Book Appointment Apply for B.SC OPTOMETRY