We all suffer from occasional red, yellowing or discoloured eyes, but if the condition becomes permanent, it may be an indication of other health issues.
Read: Eyesight and eye care basics
The sclera's purpose is to provide structure, strength, and protection to the eye. It forms the supporting wall of the eyeball, and is continuous with the cornea.
One of the main functions of the cornea is to protect the pupil and iris by deflecting sharp light.
When these parts of the eye becomes damaged, you can suffer serious visual problems and even impairment.
Diagram: inside your eye
Most commonly, damage to the white of the eye stems from aggravation caused by prolonged allergies, over-exposure to the sun, ocular rosacea, chronic medication, damage from smoking or drug abuse, computer strain or extreme tiredness.
It may also be an indication of liver problems, diabetes, hypertension and a buildup of cholesterol elsewhere in the body.
Read: Cope with seasonal allergies and reduce eye-aggravation
While having bloodshot or yellow eyes has health consequences and can be irritating, even painful, it has become a cosmetic concern for some.
People with bloodshot or discoloured eyes feel they look less attractive than their white-eyed peers and that the condition affects their self confidence.
To address the problem, there is a growing trend across the world to whiten or bleach their eyes to permanently restore whiteness.
One such treatment pioneered in Korea four years ago and now offered across the world, is by surgically stopping blood flow to some of the blood vessels in the eyes.
Dr. J.P. Dunn, an eye surgeon and medical director at Wills Eye Hospital in Philadelphia in the US, says the procedure - which can cost up to R50 000 per eye - is risky and not necessarily rewarding.
He has had to repair botched eye whitening procedures that, though rare, could lead to blindness. More commonly it leads to more redness and irritation, or even eye ulcers.
Read: Conditions that affect the cornea, including eye ulcers
Because of the high rate of complications, it has been banned in many countries.
US Ophthalmologist, Doctor Brian Boxer Wachler, has developed an eye bleaching procedure known as I-Brite to improve the white appearance of eyes.
The surgical procedure involves mapping out and separating the damaged membrane of the sclera from the underlying healthy membrane.
This procedure of removing the conjunctiva whitens and brightens the eye by delicately removing excessive red veins, yellow growths, or areas of brown pigmentation.
The blemished membrane is peeled off and, according to the doctor, after a month the body regenerates a new membrane.
The surgery takes 15 minutes and is done without anaesthesia.
What happens when you go for eye-bleaching?
This surgery is similar to the one pioneered in South Korea by Dr. Bong-Hyun Kim where, due to high rates of complications from the operation, the Korean Ministry of Health and Welfare banned the procedure in 2011, mainly due to the number of lawsuits arising.
What's our verdict?
Health24’s optometry expert Megan Goodman explains that I-Brite surgery resembles a common procedure for ptergyium excision. Pterygium is fleshy tissue that grows in a triangular shape over the cornea. It may grow large enough to interfere with vision, and surgery is required to remove it.
"The I-Brite procedure is similar to the ptergyium excision which is usually only performed as a last resort when other methods to improve vision and comfort have failed,” says Goodman.
"It is a routine procedure performed by ophthalmologists worldwide."
Lindi from SA tells shares her I-Brite experience
Is eye-bleaching safe?
Goodman says that it is difficult to say whether this type of treatment is promising, because the procedure is fairly new and not enough is known about its safety and side effects.
In her opinion the procedure seems to involve a conjunctiva resection, which means that the "affected" conjunctiva is removed.
She has some concern about a procedure that works so closely with the conjunctiva, as this membrane contains goblet cells with a substance called mucin.
“Mucin is a very important component of the tear film, in that it ‘sticks’ the other layers of the tear to the globe."
“A person is born with a fixed number of these cells and they cannot regenerate. Surgery that removes these cells could compromise the quality of the tear film, leading to dry eye,” she says.
Goodman adds that dry eye is one of the most common complaints in the elderly, even without surgery, and therefore recommends that anyone considering eye surgery of any kind should be sure extreme caution is exercised and make sure the benefits outweigh the risks.
In an article for Digital Eyeworld.org Dr Lathany, an ophthalmic surgeon and associate professor at New York Medical College, mentioned a case report that found that a 59-year-old man with a history of blepharitis after LASIK had the I-BRITE procedure done, but then presented a year later with progressive bilateral necrotizing scleritis and scleral calcification.
Eye bleaching or whitening, as done in the IBrite procedure, is not performed in South Africa.
White eyes naturally
1. Get enough sleep
Red sclera is often the result of sleep deprivation. The average adult needs about 6 to 8 hours of sleep a night.
2. Change Your Diet
Yellow sclera may be an indication of underlying liver disease, and a remedy would therefore be to consume enough fruit and vegetables and reduce salt intake. Also drink enough water.
Read: How a healthy diet protects the eyes
Alcohol, sugary beverages and drinks high in caffeine are bad for the liver, so stay clear of these if you suspect that your discoloured eyes may be related to a liver disease.
Should the cause of discoloured eyes be due to liver damage, it is important that you visit a doctor.
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Image: The Anatomy of the Eye: Shutterstock