Causes of Blindness

Cataract
Cataracts are common cause blindness and that these conditions can easily be treated and the blindness reversed.

A cataract is formed when the usually clear lens of our eyes becomes cloudy. This hinders light from entering the eye and causes vision to become blurred over time. We may also see halos around lights or feel that colors look dull.

This condition is often linked to ageing.

Prolong exposure to ultraviolet (UV) rays present in sunlight, long term use of drug like steroids and some diseases like diabetes raise the risk of developing cataracts.

Some people are born with cataracts and some develop them because of eye injuries.
We can avoid developing cataracts by wearing sunglasses with UV protection and prevent diabetes by leading a healthy lifestyle.

The standard treatment is to remove the cloudy lens and replace it with a clear artificial one. The lens can be designed to correct refractive errors like short sightedness which is a bonus to us as we will not need spectacles after the surgery.

But, in rare cases when cataracts are too severe and have damaged the cornea, this condition cannot be treated and that we are left with permanent blindness.

Undercorrected refractive errors

Undercorrected short sightedness, long sightedness, astigmatism and other refractive errors like cataracts are problems which can easily be treated.

All that we need is a pair of spectacles with lenses that correct these refractive errors.

Those with severe short sightedness can develop complications that can blind them permanently, although this rarely happen.

The problem can be so severe that it is the common cause of blindness. Undercorrected refractive errors are responsible for causing blindness in people who lost their vision in both eyes.

Short sightedness or myopia causes people to have difficulty seeing object that are far away. Myopia occurs when the eyeball grows too long and is unable to focus light rays on the retina, the membrane in the back of the eye on which image formed.

We can prevent it from developing or worsening by taking regular vision breaks like 5 minutes breaks from reading or writing and spend more time outdoors.

Glaucoma

Glaucoma causes fluid in the eye to build up which hold up the pressure inside. The high pressure damages the optic nerve that sends signals from our eyes to the brain to enable us to see.

The damage caused is irreversible and will lead to blindness in severe cases.

The diseases comes in several forms, majority will develop a form called primary open angle glaucoma. This will progresses slowly and painlessly and destroys peripheral vision before central vision, we will not notice that our vision is deteriorating.

Another form is called acute angle closure glaucoma, it occurs suddenly.

Pressure in the eye rises rapidly, causing pain and redness in the eye, blurred vision, headache and nausea.

Glaucoma linked to ageing.

The risk increases if we have family history of glaucoma, extreme short sightedness or chronic diseases like diabetes and high blood pressure.

Eye inflammation, advanced cataracts, tumours, injuries and surgery can also leads to glaucoma.

Most of the risk factors cannot be prevented. Early screening to detect the diseases is important and treatments are able to stop its progression in most cases.

The diseases are commonly treated with eye drops to lower the pressure. Laser treatment or surgeries are normally used at a later stage.

Sadly, some still end up losing their sight permanently.

Macular degeneration

Age related macular degeneration (AMD) causes the macula (the centre of the retina) to deteriorate.

It can be dry type when the yellow waste material is deposited on the macula or wet type when abnormal blood vessels grow under the macula, leak or damage it.

Exposure to high energy visible light from the sun may cause the risk of AMD. By wearing sunglasses will help to reduce or prevent AMD also by taking vitamins A, C, E, zinc and copper will slow down age related macular degeneration progression.

Regular laser therapy can seal leaky blood vessels and drugs can be injected regularly into the eye to stop it growth.


Diabetic retinopathy

Diabetic retinopathy causes abnormal blood vessels to grow over the retina and optic nerve of a diabetic person which later leak and damage the retina and nerve. It causes blurring of vision and floating black spots effect so called they seem to be seen floating. It can cause the retina to detach, damage the retina’s centre and develop into glaucoma.

The longer you have diabetes the greater your risk of having diabetic retinopathy. You should maintain your blood sugar levels to prevent it.

Laser therapy is used to burn off the abnormal blood vessels and dead parts of the retina and to prevent further damage to the eye.