Understanding Procedures at the Eye Doctor: Visual Field Testing
This morning, I personally inserted my face into the machine pictured above, in order to go through the process of a visual field test. A visual field test is a method whereby an individual’s complete scope of vision (central and peripheral vision) can be properly measured by an optometrist.
During a visual field test, a machine technically draws a pictorial map of the each individual eye’s visual fields. Considered by and large to be a subjective examination, each patient must be educated on how the test works, what their part in the exam is, and the exam itself must be fully completed in order for the doctor to receive useful information about the patient’s vision.
What Can a Visual Field Test Tell an Optometrist?
The visual field test has the ability to detect many forms of dysfunction in both the central and side vision of a patient, which may have been caused by any number of conditions, including things as severe as strokes and brain tumors, as well as conditions of the eye such as glaucoma.
While visual field exams may be conducted via the use of a machine, it is also possible for a trained technician to directly conduct the exam. One of the benefits of a test that is conducted by a machine, is that once completed, the doctor and the patient have a detailed printout of the patient’s visual field to go over together.
What Is Visual Field Testing Used For?
An optometrist may perform a visual field test most often in order to detect signs of glaucoma damage to the optic nerve of the eye. Other conditions such as retinal disease, problems associated with the eyelid, disease affecting the optic nerve, may also account for the reasons why a visual field test might be conducted.
During a patient’s visit to the optometrist for a visual field test, one can expect to go through a procedure that lasts approximately 7-8 minutes for each eye. Patients begin by covering one eye with a patch, and then placing their chin and forehead against an open portion of the machine.
While focusing on a small light in the center of the machine’s visual field, tiny lights appear in various places on the surface of the machine. Each time the patient registers the appearance of one of these lights, they are asked to click a small remote that they hold in their hands. After completing the test, the patient and doctor go over the printed record of the examination.
This article includes numerous reasons why your optometrist may want to administer a Visual Field Test. This Wikipedia entry on Visual Field Tests details the types of examination methods potentially used in the conducting of a Visual Field Test.
Video on How a Visual Field Test Works
[Photos Via: amazingeye; advancedeyecareny]