The basic facts of glaucoma


Are you experiencing problems with your peripheral or side vision? Do you have to turn your head to see what is to your immediate right or left? It might be…….Glaucoma.

The mammalian eye as a sense organ,  allows vision. Human eyes help provide a three dimensional, moving image, normally coloured in daylight according to wkikipedia. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth.

Glaucoma is a group of diseases that can damage the eye’s optic nerve and result in vision loss and blindness.It occurs when the normal fluid pressure inside the eyes slowly rises. This results in gradual painless vision loss, usually beginning in the side vision and slowly moving inwards. If left untreated, vision loss will progress until vision is completely lost.

Vision loss from glaucoma is permanent. However, with early treatment, you can often protect against serious vision loss. Majority of persons with the disease are not even aware of having glaucoma, hence it is often referred to as ‘the sneak thief of sight’.

Glaucoma is the leading cause of irreversible blindness and the second most common cause of blindness worldwide.

What is optic nerve?
The optic nerve is a bundle of more than one nerve fibers. It connects the retina to the brain. The retina is the light sensitive tissue at the back of the eye. A healthy optic nerve is necessary for good vision.

How does open-angle glaucoma damage the optic nerve?
In the front of the eye, is a space called the anterior chamber. A clear fluid flows continuously in and out of the chambers and nourishes nearby tissues. The fluid leaves the chambers at the open angle where the cornea and iris meet. When the fluid reaches the angle, it flows through a spongy meshwork, like a drain and leaves the eye.

Sometimes, when the fluid reaches the angle, it passes too slowly through the meshwork drain. Asthe fluid builds up, the pressure inside the eye rises to a level that may damage the optic nerve. When the optic nerve is damaged from increased pressure, open-angle glaucoma – vision loss – may result. That’s why controlling pressure inside the eye is important.

Does increased eye pressure mean that you have the disease?

Increased eye pressure means you are at risk for glaucoma, but does not mean you have the disease. A person has it only if the optic nerve is damaged. If you have increased eye pressure but no damage to the optic nerve, you do not have glaucoma. However, you areat risk. Follow the advice of your eye doctor – ophthalmologist.

Can I develop glaucoma without an increase in my eye pressure?

Yes. Glaucoma can develop without increase in eye pressure. This form of glaucoma is called low-tension or normal-tension glaucoma. It is not as common as the open-angled glaucoma.

Who is at risk of having the disease?

People who are;

  • Age > 40 years
  • Intraocular pressure . 20mmHg
  • Systemic disease – Diabetes mellitus, systemic hypertension
  • Family history – Glaucoma is frequently inherited
  • Race – more common, develops earlier, and is more severe in blacks than in whites.
  • Refractive error – myopia/shortsightedness

How do I know that I have it?

Vision problems

At first, there no symptoms. Vision stays normal and there is no pain. However, as the disease progresses, a person with the disease may notice his or her vision gradually failing from the side. That is, objects in front may still be seen clearly, but objects at the periphery ( side ) may be missed.

Without treatment, people with the disease will lose their peripheral ( side ) vision. They seem to be  looking through be tunnel. Over time, straight-ahead vision may decrease until no vision remains.

The only way to find out if you have the disease is to see a specialist eye doctor ( an ophthalmologist ) who will carry out specialized tests that will help determine if you have glaucoma or if you are at risk for developing it.

How is it treated or managed?

There is no cure for it and visual loss is irreversible. However, glaucoma can be treated with eye drops, laser or surgery ( trabeculectomy ) – these will lower the pressure in the eye and thus prevent further visual loss and preserve existing vision, that is treatment is preservative.

What can you do to protect your vision if you have glaucoma?

Studies have shown that the early detection and treatment of the disease is the best way to control it. So, if you fall into one of the high-risk groups for the disease, make sure you have have your eyes examined through dilated pupils once a year by an ophthalmologist.

If you are being treated for glaucoma, the most important thing you can do to protect your vision is to follow your eye doctor’sinstructions – take medications as prescribed and return for regular eye checkups as recommended.

Since vision loss from glaucoma is permanent, it needs to be diagnosed early and appropriate treatment commenced as early as possible.


Leave a Reply

Your email address will not be published. Required fields are marked *