Dr Dulcy on Glaucoma: the thief of vision
OVER 40?: SEE EYE DOCTOR OFTEN
Most people do not have symptoms.First sign is often the loss of side vision.
It usually affects both eyes but it may be worse in one than the other.
Glaucoma is a disease that affects pressure within the eye, damaging the optic nerve. This leads to peripheral visual loss. It is one of the leading causes of blindness worldwide, and four in 50 South Africans over the age of 40 suffer from glaucoma.
Glaucoma usually does not produce symptoms until vision is already severely damaged. But if diagnosed early, the disease can be controlled and permanent vision loss can be prevented.
The disease may be inherited and may not show up until later in life. If you are over 40 and have a family history of the disease, you should get a complete eye exam from an ophthalmologist every one to two years.
Most people with glaucoma have no early symptoms or pain. You need to see your eye doctor regularly so she can diagnose and treat glaucoma before long-term visual loss happens. If you have diabetes, you may need to go to the doctor more often. Without treatment, glaucoma can cause total permanent blindness within a few years.
Causes
Glaucoma is the result of high fluid pressure inside your eye. This happens when the liquid in the front part of the eye doesn’t circulate the way it should.
Normally, the fluid, called aqueous humor, flows out of your eye through a meshlike channel. If this channel gets blocked, the liquid builds up.
The reason for the blockage is unknown, but doctors know it can be passed from parents to children.
Less common causes include a blunt or chemical injury to your eye, severe eye infection, blocked blood vessels inside the eye and inflammatory conditions.
It does happen that sometimes eye surgery to correct another condition can bring it on. It usually affects both eyes, but it may be worse in one than the other.
There are two main types of glaucoma:
Open-angle glaucoma: This is the most common type; also called wide-angle glaucoma. The drain structure in your eye called the trabecular meshwork looks normal, but fluid does not flow out like it should.
Angle-closure glaucoma: You may also hear it called acute or chronic angle-closure or narrow-angle glaucoma. Your eye does not drain right because the angle between your iris and cornea is too narrow. Your iris is in the way. This can cause a sudden buildup of pressure in your eye. It is also linked to farsightedness and cataracts, a clouding of the lens inside your eye.
You’re more likely to get it if you:
Are over 40 Have a family history of glaucoma Have poor vision Have diabetes Take steroid medications like prednisone Have had trauma to one eye or both
Symptoms
Most people do not have any symptoms. The fi rst sign is often a loss of peripheral, or side, vision. That can go unnoticed until late in the disease. That is why glaucoma is often called the “sneak thief of vision”.
Detecting glaucoma early is one reason you should have a complete exam with an eye specialist every one to two years.
If you have any of the following sympate symptoms, seek immediate medical care: Seeing halos around und lights Vision loss Redness in the eye e Eye that looks hazy zy (particularng (particularly in infants) Nausea or vomitting Eye pain Narrowed (or tunnel) nel) vision
Diagnosis
Your eye doctor will l use drops to open or dilate your our pupils and examine your eyes. The doctor will check your opou optic nerve, and if you have glaucoma, it will look a certain way. Glaucoma tests are painless and quick. gery, or microsurgery.
Eye drops: These either reduce the formation of fluid in the eye or increase its outflow. Side effects may include allergies, redness, stinging, blurred vision, and irritated eyes. Some glaucoma drugs may affect your heart and lungs. Tell your doctor about any other medications you are taking or are allergic to.
Laser surgery: This procedure can slightly increase the flow of the fluid from the eye if you have open-angle glaucoma. It can stop fluid blockage if you have angle-closure glaucoma.
Microsurgery: In a procedure called a trabeculectomy, the doctor creates a new channel to drain the fluid and ease eye pressure. Sometimes this form of glaucoma surgery fails and has to be redone.
Surgery can cause temporary or permanent vision loss, as well as bleeding or infection. Talk to your eye doctor to find out which glaucoma treatment is right for you.
Prevention:
Glaucoma cannot be prevented, but if you diagnose and treat it early, you can control it. Usually once you have lost the vision, it cannot be restored. However, lowering eye pressure can help preserve the sight you still have. Most people with glaucoma who follow their treatment plan and have regular eye exams do
not go blind.