There are various methods to check the visual field and this kind of test is an important tool for glaucoma and other eye conditions which can cause damage to the visual field.
When a visual field is tested, the goal is to measure how far a person can see in all directions when he or she is focusing in on a central target. The patient is looking at one point, but we want to know how much can be seen beyond and surrounding that target in the periphery. The eye doctor will be able to measure the extent of what you can and cannot see in your visual field and this is known as perimetry
There are various eye conditions and disorders which cause a change or loss of one’s visual field. Testing this aspect of a patient’s vision can help detect eye diseases. Certain conditions cause a loss of visual field in distinct ways such as specific patterns or shapes which make it easier to identify the cause for the loss of one’s visual field. For example, glaucoma causes visual field loss in very specific ways. Testing the visual field can be a crucial tool in diagnosing and monitoring a person’s eye condition.
If you have an eye disease such as glaucoma or there is reason to believe you might have it, then your eye doctor will test your visual field. After a diagnosis of a disease which affects the visual field, you will continually be monitored to assess the progression of the condition. In glaucoma, there is a typical progression of certain visual field defects and therefore, by testing the visual field, the eye doctor can gain a better understanding of what stage of glaucoma you have.
Visual field testing can be used for a wide variety of diseases which can affect your visual field. Some of these conditions include:
There are different types of visual field testing methods ranging from an approach that does not require equipment to methods that involve very intricate machinery.
There are two methods which are applied for either manual or automated perimetry: