Glaucoma is detected through a comprehensive eye exam that includes:
Eye Chart
This eye chart test measures how well you see at various distances. A tonometer measures pressure inside the eye to detect glaucoma.
Visual Field Test
This test measures your side (peripheral) vision. It helps your eye care professional tell if you have lost side vision, a sign of glaucoma.
Dilated Eye Exam
Drops are placed in your eyes to widen, or dilate, the pupils. Your eye care professional uses a special magnifying lens to examine your retina and optic nerve for signs of damage and other eye problems. After the exam, your close-up vision may remain blurred for several hours.
Regular glaucoma check-ups include two routine eye tests: tonometry and ophthalmoscopy.
Tonometry
The tonometry test measures the inner pressure of the eye. Usually drops are used to numb the eye. Then the doctor or technician will use a special device that measures the eye’s pressure.
Ophthalmoscopy
Ophthalmoscopy is used to examine the inside of the eye, especially the optic nerve. In a darkened room, the doctor will magnify your eye by using an ophthalmoscope (an instrument with a small light on the end). This helps the doctor look at the shape and color of the optic nerve.
If the pressure in the eye is not in the normal range, or if the optic nerve looks unusual, then one or two special glaucoma tests will be done. These two tests are called perimetry and gonioscopy.
Perimetry
The perimetry test is also called a visual field test. During this test, you will be asked to look straight ahead and then indicate when a moving light passes your peripheral (or side) vision. This helps draw a “map” of your vision.
Gonioscopy
Gonioscopy is a painless eye test that checks if the angle where the iris meets the cornea is open or closed, showing if either open-angle or closed angle glaucoma is present.