What is Glaucoma?
Glaucoma is an eye disease that involves damage to the optic nerve. This nerve sends visual signals to the brain, where they are processed into what you “see”. No one knows what causes glaucoma, but pressure buildup in the eye is proven to be a major risk factor.
When the pressure in the eye gets too high, the optic nerve can get damaged. This damage causes some signals from the eye not to reach the brain. The result is that you can’t “see” everything your eye sees. This leads to reduced visual field, and if not managed, may even lead to blindness.
Glaucoma is one of the most common causes of preventable blindness in the world. There is no cure but early detection and proper treatment, can help you manage the disease and preserve your vision.
Who gets Glaucoma?
Glaucoma can affect people of every race, gender, and nationality. Anyone can develop glaucoma, but some people are at greater risk than others. Studies have proven that anyone who meets one or more of the following criteria is at increased risk:
- Over the age of 40: risk increases with increasing age
- Family history of glaucoma: risk is higher in relatives of people with glaucoma
- High intraocular eye pressure (IOP): eye pressure increases with age
- Ethnicity: glaucoma is more common and more severe in persons of African origin
- Near sightedness
- Other medical diseases, including diabetes, high blood pressure and migraine
- Regular, long-term use of glucocorticosteroids (e.g. cortisone)
- Previous eye injury
If you have any of these risk factors, it is important that you get regular eye check ups.
TYPES OF GLAUCOMA
A partial blockage in the drainage canals causes the IOP to rise slowly over time. The continuous high IOP causes optic nerve damage, resulting in visual field loss. The loss of eyesight is very gradual and you only become aware of the impact when the optic nerve is damaged extensively. This type of glaucoma is the most common form of glaucoma.
This is a far less common form than open-angle glaucoma. It is also called acute glaucoma. The drainage system is blocked by the iris ( the coloured part of your eye). The fluid is not able to drain through the little canals. It is very different from open-anle glaucoma because the pressure rises very quickly and it can also be very painful; with severe headaches, eye pain and nausea. Unless this condition is relieved promptly, blindness can result very quickly.
This is a rare form of glaucoma. The optic nerve is damaged even though IOP is not high.
Can occur as the result of an eye injury, inflammation or a tumor, or in advanced cases, cataracts or diabetes. This type might be mild or severe.
Occurs in infants, it is a very rare condition that develops as a result of incomplete development of the eye’s drainage canals during the prenatal period. The structural defects can be corrected with microsurgery.
Symptoms of glaucoma
Many people don’t know they have glaucoma until they lose some of their eyesight. However, ophthalmologists can detect and treat glaucoma before most patients experience any symptoms. Glaucoma develops slowly over time, which is why many patients will go years before noticing any symptoms. Patients with glaucoma may experience a gradual narrowing of their peripheral vision. This loss of eyesight is also called “ tunnel vision.” Unfortunately, loss of vision due to optic nerve damage can’t be reversed .
Unfortunately, there is no cure for glaucoma. The good news is that glaucoma can be treated effectively when caught early. Years of research have led to the discovery of numerous medications that have helped preserve the vision of millions of people around the world.
The primary effect of most glaucoma medications is lowering IOP by either increasing the flow of the fluid (aqueous humor) out of the eye, or by decreasing the production of aqueous humor. This has been proven over the years to be an effective way to help prevent or slow down vision loss in glaucoma patients.
There are several different types of medications. Your doctor will try to find the right medication(s) that will get your IOP to a desirable range and control it over time. He or she will also take into consideration your health and the potential for side effects.
Sometimes, the doctor performs a peripheral iridotomy using an Nd : YAG laser for narrow angle glaucoma. The laser creates a small hole in the peripheral iris which improves the circulation of fluid inside the eye and widens the anterior chamber. This can lower the intraocular pressure.
If treatment with one or more medications is unsuccessful, or laser isn’t recommended for you, then your doctor may recommend a surgical procedure called a trabeculectomy. This is usually done as an outpatient surgery. You are awake but don’t feel any pain since your eye is numbed.
During a trabeculectomy, a new drain is made in your eye so that fluid can bypass the clogged drainage holes and drain more freely.
How long due I continue with medication?
Glaucoma is a chronic disease that has no cure and requires medication for the rest of the patient’s life to preserve their vision.