The most common type of glaucoma is painless. Left untreated, it slowly destroys vision. In fact, most people who have chronic glaucoma are not aware that they are gradually robbed of their eyesight. In most cases, there are no warning symptoms and, by the time vision problems develop, irreversible visual damage may already have occurred.
The goal of glaucoma treatment is to lower the pressure in your eye, improve fluid drainage or reduce fluid production. Your glaucoma doctor at Virginia Eye Consultants may recommend eye drops, oral medications or surgery, such as Trabectome or the Glaukos iStent procedure.
Is not nearly as common as chronic glaucoma. Unlike the gradual destruction of vision that occurs in the chronic condition, acute glaucoma is marked by sudden severe pain in and around the eye and is often accompanied by nausea and vomiting. In order to alleviate the pressure and prevent further eye damage, emergency treatment, usually laser surgery, is required.
Screening for Glaucoma
In an effort to catch glaucoma early, screening has become widespread and may initially be done by a wide variety of health professionals.
Your eye care professional, optometrist, or family doctor may test your eye pressure. It can also be checked in a health care clinic or at your place of work. If the screening suggests that your pressure is elevated, further tests will be performed to establish the diagnosis of glaucoma. Because chronic glaucoma seldom causes symptoms, it’s extremely important for you to have a thorough eye exam around age forty- even if you have no complaints about your vision.
The Glaucoma Exam
Often a general eye examination begins with a visual acuity test that determines how sharp your vision is. Using one eye at a time, you’ll read a chart of letters or numbers of varying sizes from a set distance (often twenty feet). Then you may be asked to view the chart through an instrument known as a refractor. By shining a light through the refractor onto the retina, your doctor can determine if you need glasses.
A slit lamp is a microscope that magnifies and illuminates the cornea, iris, and lens. It aids your doctor in finding conditions such as cataracts and corneal problems. After your vision is checked, your doctor will examine the internal structures of the eye, including the optic nerve. Using an ophthalmoscope, a hand-held instrument, the doctor can see changes in the optic nerve that are characteristic of glaucoma. After the routine examination is completed, a series of specially designed tests are given to help in the specific diagnosis of glaucoma.
The diagnosis of glaucoma is confirmed by an array of diagnostic tools that allow your eye doctor to identify signs of glaucoma long before you have any symptoms. Your doctor may begin with tonometry, which measures the pressure in your eye. Another important test checks your side (peripheral) and central vision. Your doctor may examine the interior structures of your eye using gonioscopy. If glaucoma is diagnosed, your progress will be closely monitored during regular examinations.
Your examination will test your field of vision, including peripheral and central vision. This test is helpful in determining if your vision has begun to be affected-and, if so, to what extent. Your doctor may use the computerized vision test, the Goldmann perimeter screen test, or the tangent screen test to examine your field of vision. One eye is tested at a time.
During the computerized vision test, the examiner will ask you to place your chin on a stand in front of a screen connected to a computer. While looking straight ahead, you press a button whenever a light appears in view. The computer provides a printout of your field of vision. The Goldmann perimeter screen test is similar except that a computer is not used. An examiner records your responses as you indicate when a light comes into view. With the tangent screen test, the examiner uses a marker in place of a light to map your field of vision.
Another test, called gonioscopy, involves gently placing a special lens that contains a mirror on your eye. The doctor can look inside your eye to see the drainage area that can be a problem in glaucoma. Because the area between the iris and the cornea can be seen, this test is especially helpful in determining whether the angle between the cornea and iris has been narrowed. Gonioscopy may help your doctor diagnose the type of glaucoma you have.
What happens after diagnostic testing?
Once your diagnostic tests have been completed and glaucoma has been diagnosed, your doctor may monitor the progression of the disease with special photographs of the optic nerve. Your doctor can check for progressive enlargement of the optic cup, which indicates continuing damage from the elevated eye pressure. Your doctor may also note blood vessel changes in the optic cup, another sign of glaucoma progression. A special camera for photographing the optic nerve is often used during your eye examinations. Your doctor will advise you how often your eyes will need to be checked.
Occasionally, a person may have a “borderline” eye pressure, which means that, although the pressure is elevated, there is no evidence of glaucoma damage. If you are a glaucoma suspect with a borderline pressure, your doctor may not prescribe medication immediately. Instead, your pressure will require monitoring by your doctor so that if changes do occur, treatment can be started.
Can glaucoma be inherited?
Glaucoma tends to run in families, and if either of your parents or any of your grandparents had it, you have a higher than average chance of developing the disease. Although glaucoma is rare in children, it is a leading cause of blindness in people over forty.