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Visual field testing is done for a number of different reasons, but most often to test or manage patients who have glaucoma. So just what is this test that your eye doctor wants to have? It can be referred to by different names; automated perimetry, visual field testing, test threshold, SITA (slang for Swedish Interactive Thresholding Algorithm) or various other terms. The test method was originally called a tangent screen, which is a black square of suspended materialon the wall. The perimeter of Goldmann Bowl was next and it was a manual version a bit 'as the automatic use your ophthalmologist today. Your sensitivity to light on the retina (the light sensitive layer lining the eye) looks like a topographical map of a hill. The most delicate point is in the center, as the highest point on a hill and as you move away from this central point of view the tissue is less sensitive to light (as the shortest odds on a topographic map). The higher the center point to the macula, which is why the macular degeneration is only a small area of compromise to have devastating effects on vision. A visual field test measures the sensitivity of eyes out in the periphery of the retina. more eye exams only test the small central peak of the hill. The visual field test measures not only the peripheral retina, but to some extent the location of the nerves of the eye through the brain.
Your> Test the visual field will be either a screening test or threshold test. screening tests are used by an ophthalmologist to check eye diseases and vision problems in a method similar to how your family doctor should do blood pressure only to read the screen for high blood pressure. If the family doctor was more interested would like multiple readings and analysis methods more refined, perhaps a cardiac stress test to see how your heart and blood pressure on underdifferent conditions with a much larger number of data points. Similarly, a threshold visual field test done by your doctor eye is much more detailed testing. As the hill of vision narrows with age, a threshold test to compare the results of a population sample of similar age without glaucoma and other eye diseases. The examination of the eyes will produce a detailed statistical analysis.
You can expect the trial to take about 3 to 5 minutes for each eye, in most cases. L 'vision test is standardized for the eyes are dilated so you need to plan on 30 to 60 minutes in the office even if the visual experimentation is quite short. For the test on the real field of view, we sit with a half a bowl as a tool in front of you. If you wear contact lenses should be removed. The tools of the visual field to calculate a different recipe to compensate for the distance you are viewing. Prescriptionlenses are placed in a holder in front of your eyes to replace contact lenses or glasses. One eye is covered and you need to fixate on a central span of the test. A device similar to a mouse of a computer will be held in one hand and simply click it whenever you think you see a small point of light flash from anywhere in the bowl. The flashes are very short and may be close to where your eye is fixed on or very far in the peripheral field of vision. L 'brightness of the flash of light varies from very weak to very visible. In our Eye Center, which usually starts the test sequence in demo mode to familiarize patients with the process.
Many people worry about their answers, if clicked too late, accidentally clicked, and are uncomfortable with the darkness of some points of light at the limit of visual perception. This should not be a concern. Test the visual field is varied and sophisticated todaymeasures your mistakes, retests them, and provides an index that tells us how much variation there was in your eye examination. If reliability is too low we repeat the test on another day and almost always find the reliability of the examination halls eye to acceptable levels. There are also a factor for changes made by software that you can have cataracts or other conditions that are not in the retina and visual journey through the brain. With most of the tools of the visual fieldYou can pause the test yourself by holding down the clicker. That can give you the opportunity to relax, change positions, or ask a question to clarify what the answers should be. We usually start in a demonstration mode to familiarize patients with the process and go to the actual test once the patients seem to be comfortable. You can always request a first-time demonstration.
Besides glaucoma, a visual field test can be used to diagnose pituitary tumors, neurologicalproblems and unexplained loss of vision and headache.
One last point, if you live in the area such as Fort Collins, Colorado, the sun is very bright after your eyes are dilated. Be sure to leave with the sunglasses temporary if you do not already have high-quality sunglasses.
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