The visual field test is done to determine your peripheral vision, or side vision and is required to diagnose, and monitor glaucoma over time.
A spot that is repeatedly presented in different areas of your peripheral vision, and each time you see it, you are required to click a button. Your doctor will ask you to keep looking ahead at the fixation light, and not look at this moving light, and press the button even if you think you see it.
Glaucoma Diagnosis and Staging
Your doctor will recommend the visual field test if she suspects you may have glaucoma. Other conditions in which she may recommend the test include diseases that affect the visual pathways of the brain, including tumors and stroke, and diseases of the optic nerve.
In case of glaucoma, the visual field data is used to diagnose, as well as determine the severity of disease. This helps your doctor choose your target eye pressure and the frequency of follow-up examinations.
Follow up Visits for Progression
After the initial diagnosis the doctor will ask you to come back for a repeat. She may recommend the test after three to twelve months, depending on how severe your disease was at diagnosis.
In case the visual fields shows any sign of deterioration, your doctor may change your medication to lower your eye pressures further.
Also, since the test is subjective, and you may get tired while doing it, your doctor may recommend a repeat of the test to confirm the results.
Is There An Easier Test?
Almost all patients dislike the visual field test. Not because it is painful, but becase it is tedious and often, unnerving. Remember, all glaucoma doctors dislike it as much because its results are often difficult to explain and vary from day to day, depending on how attentive the patient is on that day.
That said, there is really no alternative available on date to accurately measure and document optic nerve function, and your peripheral vision. This information helps your doctor make treatment decisions, and as on date, is irreplaceable in clinical practice.
What Can I Do To Do Well On The Visual Field Test?
Here’s a list of help you cope better:
- Make sure you sleep well the night before the test.
- Be comfortable, relax, and only when you think you are ready, start with the test.
- Press the button when you are sure you see the light spot.
- Don’t press the button when you cant see the light so you have a better result. The machine knows when you do that. Its called a false positive error.
- Do not move your eyes away from the central fixation light. the machine knows when you look around, searching for the light.its called a fixation loss, and the machine flags the test as unreliable.
- Your doctor will explain the long press to you. If you are getting tired, press the button, and hold the pressure. The test will stop. You can then recline your head, blink, and generally relax, before starting again.
