The cornea is the clear part of the front of the eye that allows light to pass into the eye, enabling a person to view things.
Presence of scar tissue following eye injury or post eye surgery or infection can result in the cornea becoming cloudy or opaque.
The scar tissue blocks the light from passing through the cornea, causing vision degradation and loss leading to a distorted vision or at times even vision loss.
In the absence of the scar tissue, the light would pass through the cornea where it would normally be bent and then focused through the iris onto the retina.
Corneal opacity can affect people of any age and is mostly seen in developing countries due to the eye injury and vitamin A deficiency as the primary cause.
Corneal opacity is the leading cause of blindness, globally and is ranked fourth after cataract, glaucoma, and age related macular degeneration as the cause of blindness.
The cornea consists of a strong, tough tissue composed of five different layers, each with a specific function.
The cornea protects the eye from dust, germs, UV rays, and other foreign substances. Along with the lens, it bends light rays onto the retina so that images appear in focus.
If the corneal shape is excessively steep, flat, or not completely round, it can cause nearsightedness, farsightedness, or astigmatism.
These are called refractive errors. Certain types of corneal diseases can change the shape of the cornea.
Following could be the symptoms of corneal damage:
- Redness and swelling of eyelid and eye tissues
- Blurred vision
- Irritation
- Light sensitivity
- Tearing
- Sensation of something in the eye
- Eye discharge
- Cloudy area on the cornea
- Loss of vision
The cornea protects the eye from dirt, debris, and germs, and to let the light in and bend it.
Cornea governs more than half of the eye’s focusing ability. Despite being very thin, cornea has five layers. Corneal clouding is the result of the damage to any of these layers.
Decreased vision or vision loss is one of the most common symptoms of corneal opacity.
A person may feel like there is something in his eye, even after flushing the eye and having someone look in it and may also suffer from sensitivity to light and unexplained eye redness, as well as have an area on the eye that looks cloudy or milky.
Factors that increase the likelihood of developing corneal opacity are measles, vitamin A deficiency, viral infections such as herpes zoster or shingles, ocular or eye herpes, and conjunctivitis or pink eye. Having an eye injury due to some chemical or physical reason or wearing contact lenses for a long-time can also increase the risk of corneal opacity.
When corneal opacity is suspected, a physician will use a slit lamp to examine the various structures of the eye.
With the use of a magnifying lens and eye drops that dilate the pupils and numb the eye, the physician can check for foreign bodies, and corneal scarring.
Majority of corneal opacity treatment includes oral medications or steroid and antibiotic eye drops.
In more serious cases, laser surgery helps remove the scarring from the corneal surface. Severe cases may warrant a need for cornea transplant.
In order to decrease the risk of corneal opacity, one needs to be careful while using contact lens and ideally should follow the guidelines for use and care of contact lenses.
Eye protection should be used wherever there is a risk of an eye injury. Every eye infection, be it mild or severe, should be monitored carefully by consulting the doctor.
OPTOMETRY-SHARP VISION
Optometrist