To detect glaucoma, our ophthalmologist will test your visual acuity and visual field as well as the pressure in your eye. Regular eye exams help to
monitor the changes in your eyesight and to determine whether you may develop glaucoma.
During a glaucoma evaluation, your ophthalmologist will perform the following tests:
Tonometry measures your IOP by determining how your cornea responds when an instrument (or sometimes a puff of air) presses on the surface of your
eye. Eyedrops are usually used to numb the surface of your eye for this test.
For this test, your ophthalmologist inspects your eye’s drainage angle the area where fluid drains out of your eye. During gonioscopy, you sit in a
chair facing the microscope used to look inside your eye. You will place your chin on a chin rest and your forehead against a support bar while
looking straight ahead. The goniolens is placed lightly on the front of your eye, and a narrow beam of light is directed into your eye while your
doctor looks through the slit lamp at the drainag angle.Drops will be used to numb the eye before the test.
With this test, your ophthalmologist can evaluate whether or not there is any optic nerve damage by looking at the back of the eye (called the fundus).
There are two types of ophthalmoscopy: direct and indirect. With direct ophthalmoscopy, your ophthalmologist uses a small flashlight-like instrument
with several lenses that magnifies up to about 15 times. With indirect ophthalmoscopy, the ophthalmologist wears a headband with a light attached
and uses a small handheld lens to look inside your eye. Indirect ophthalmoscopy allows a better view of the fundus, even if your natural lens is
clouded by cataracts.
Visual field test
The peripheral (side) vision of each eye is tested with visual field testing, or perimetry. For this test, you sit at a bowl-shaped instrument called
a perimeter. While you stare at the center of the bowl, lights flash. Each time you see a flash, you press a button. A computer records your response
to each flash. This test shows if you have any areas of vision loss. Loss of peripheral vision is often an early sign of glaucoma.
Sometimes photographs or other computerized images are taken of the optic nerve to inspect the nerve more closely for damage from elevated pressure
in the eye.
Different scanners may be used to better determine the configuration of the optic nerve head or retinal nerve fiber layer.
Each of these evaluation tools is an important way to monitor your vision to help ensure that glaucoma does not rob you of your sight. Some of these
tests will not be necessary for everyone. Your ophthalmologist will discuss which tests are best for you. Some tests may need to be repeated on
a regular basis to monitor any changes in your vision caused by glaucoma.
Visit the American Academy of Ophthalmology for more information on glaucoma testing and treatments.