Glaucoma is the name for a group of eye diseases that damage the optic nerve. This nerve carries information from the eye to the brain. When the nerve is damaged, you can lose your vision. It usually happens when fluid builds up in the front part of your eye. That extra fluid increases the pressure in your eye, damaging the optic nerve.
Glaucoma is an often painless but serious eye condition. Because, in its early stages, it usually has no symptoms. By the time you notice problems with your sight, the disease has progressed. At this point, irreversible vision loss has already occurred and additional loss may be difficult to stop.
It is one of the most common causes of legal blindness in the world. At first, people with glaucoma lose side (peripheral) vision. But without treatment, vision loss may get worse. This can lead to total blindness over time.
What causes glaucoma?
The exact cause isn’t known. Experts think that increased pressure in the eye may cause the nerve damage in many cases. Normally, fluid in your eye nourishes the eye and keeps it healthy. After the fluid circulates through the eye, it empties through a drain in the front of your eye.
In people who have glaucoma, the fluid doesn’t drain properly. Instead, it builds up and causes increased pressure in the eye. This pressure damages the optic nerve and causes vision loss. However, it is possible to develop glaucoma even if your eye pressure is normal.
What are the different types
There are 2 main types of glaucoma found in adults:
Open-angle glaucoma (OAG).
This is the most common type. It usually affects both eyes at the same time. Your vision gradually gets worse. But it gets worse so slowly that you may not notice it. According to the American Academy of Ophthalmology (AAO), OAG affects an estimated 2.2 million people in the United States, and that number is expected to increase to 3.3 million by 2020 as the U.S. population ages.
Closed-angle glaucoma (CAG)
It usually affects one eye at time. It produces sudden symptoms such as eye pain, headaches, and red eyes. CAG can happen suddenly and be a medical emergency. The attack may last for a few hours, and then return again for another round, or it may be continuous without relief. Each attack can cause progressively more vision loss.
Who gets glaucoma?
Risk factors for glaucoma include:
- Being 40 years of age or older.
- A family history of glaucoma.
- High pressure in the eyes.
- Heart disease.
- Near-sightedness (it is difficult for you to see objects in the distance).
What are the symptoms?
If you have OAG, the only symptom you are likely to notice is loss of vision. You may not notice this until it is serious. That’s because the eye that is less affected makes up for the loss at first. Side vision is often lost before central vision.
Symptoms of CAG can be mild, with symptoms like blurred vision that last only for a short time. Severe signs of CAG include longer-lasting episodes of blurred vision or pain in or around the eye. You may also see coloured halos around lights, have red eyes, or feel sick to your stomach and vomit.
If there are no recognizable symptoms, how can I tell if I have glaucoma?
The best way to detect glaucoma is by having your eyes examined. The (AAO) recommends that everyone get a baseline eye exam by age 40 or sooner if you have risk factors for eye disease, such as high blood pressure or diabetes. The AAO also recommends glaucoma screening every two to four years, depending on your age and if you have any risk factors.
Diagnosis can be made during routine eye examinations. Your ophthalmologist (eye doctor) will give you a comprehensive eye exam. This will include several tests. These tests include:
- Visual acuity test – measures how well you see at different distances.
- Gonioscopy, which is an examination of the eye’s drainage angle
- Visual field test – measures your side vision.
- Dilated eye exam – allows your eye care professional to examine your retina and optic nerve for signs of damage or other eye problems.
- Tonometry – measures the pressure inside the eye.
What treatment options are available?
Glaucoma can’t be cured. But there are things you can do to help. The purpose of treatment is to lower the pressure in the eye. This will prevent further nerve damage and vision loss. Treatment is with medicated eye drops. Medicines can also be orally (in pill form).
It is important to take glaucoma medicines regularly, as prescribed by your eye care professional. Because glaucoma doesn’t cause symptoms, you might forget to take your medicine. But you need to use the drops or pills regularly to help control the pressure in your eye.
When eye drops don’t help relieve pressure, you may need other treatment. Laser treatment uses a laser to open up the drain where fluid flows out. It is a painless procedure. If that doesn’t work, you may need surgery to create a new channel where fluid can flow out of your eye.
How do you cope with glaucoma?
If you have vision loss, you can keep your quality of life. You can use vision aids, such as large-print items and special video systems, to help you cope with reduced eyesight. Support groups and Counselling can also help you deal with vision loss.
How do you prevent it?
There’s nothing you can do to avoid getting glaucoma. But you can prevent it from having a large impact on your vision. The best way to do this is by getting doing routine eye examination. Maintaining an active lifestyle appears to be an effective way. You also can reduce your risk for glaucoma by not smoking, maintaining a healthy weight, and eating a varied and healthy diet.
I have glaucoma and cataracts. What can be done to help?
A cataract is a clouding of the lens of the eye that prevents light from entering. Since many people develop cataracts as they age, many people with glaucoma also have them. The 2 problems can be treated in many patients using a single combined procedure. Vision restoration is more quickly and usually no need for further surgery.