What is glaucoma?
Glaucoma is a condition in which the nerve cells that transmit information from the eye to the brain become damaged. This prevents visual information from getting from the retina in the eye to the brain.
Glaucoma is often associated with a build-up of pressure in the eye. The eye is normally filled with fluid that is constantly being replaced. If excessive amounts of fluid are produced or if it cannot drain away properly, the pressure inside the eye can become extremely high, but in other forms the pressure may remain normal.
What causes glaucoma?
The exact causes of glaucoma are unknown. In some cases, the drainage network of eye may not be formed properly, or may become blocked by natural materials or due to injury. In other cases, there is no clear cause.
Is the damage that occurs in glaucoma serious?
If untreated, glaucoma can cause blindness. As the nerve cells are progressively damaged, the ability to see objects in different parts of the visual field is lost. This can progress until only central vision is left or until the person is completely blind. The longer the disease is left untreated, the greater is the likelihood of damage.
Once damage has occurred, it cannot be reversed although often it is possible to prevent further damage. Modern examination techniques and treatment have made glaucoma a rare cause of blindness in Australia.
What are the signs of glaucoma?
Often you will not be aware that you have glaucoma until it is too late. Usually there are no symptoms until permanent damage has occurred.
In some cases, the increased pressure in the eye will cause blurred vision, apparent coloured rings around light, loss of side vision, and pain and redness of the eye.
How is glaucoma detected?
To diagnose glaucoma, the optometrist looks at the nerve fibres at the back of the eye, examines the eye’s drainage network, measures the pressure in the eye with a special instrument called a tonometer and tests the field of vision. These tests are simple and painless.
If glaucoma is detected at an early stage and treated promptly, it can usually be controlled with little or no further vision loss. This is why regular optometric examinations are so important.
Can glaucoma be prevented?
No, early detection and treatment are the best ways to control glaucoma.
Should I be tested for glaucoma?
People with a blood relative who has suffered from glaucoma and people over 40 years of age are more at risk and should have their eyes checked regularly by an optometrist.
There are various tests your optometrist can do and they include:
- Tonometry – a simple and painless measurement of the pressure in the eye
- Ophthalmoscopy – an examination of the back of the eye to observe the health of the optic nerve
- Visual Field Test – a check for the development of abnormal spots
How is glaucoma treated?
Firstly, eye drops and medicine are used to treat glaucoma. Surgery may be necessary if the blockage in the drainage system cannot be removed in other ways.
Visit, call or make an appointment on-line with one of our centres if you are concerned about the health of your eyes or would like to book an appointment for an eye examination.