Corrective lens, What type of lens corrects astigmatism?
People with Poor Vision are recommended to see an eye doctor to have their vision checked. In most cases, individuals who suffer from poor vision are diagnosed with astigmatism. Astigmatism is a condition wherein the curvature of your cornea is imperfect. In other words, the curvature of your cornea doesn’t match with the curvature of your lens. According to statistics, 1 in every 3 Americans is diagnosed with astigmatism each year.
When the curvature of the cornea is abnormal light will get inside your eye causing you to see blurred images. A normal and healthy cornea is round and is shaped like a ball. For individuals with astigmatism, their cornea takes on the shape of a football, which explains the blurred images. Another reason for astigmatism is when the lens is irregularly shaped. The lens is found at the back of your cornea.
How Is Astigmatism Diagnosed?
How do you diagnose astigmatism? A lot of kids are actually born with this condition without them knowing it. The only time they’ll know if they have it is when they undergo an eye test. Most children struggle with their academics because they are having trouble reading books. To know whether your kids have astigmatism or not let them undergo regular eye tests. An eye doctor may use the following methods to check the eyes:
#1: Visual Acuity Test
In a visual acuity test, you will be asked to read different letters printed on a chart. The sizes of the letters become smaller as you go down each line.
#2: Astigmatic Dial
Your eye doctor may also use a different chart called an astigmatic dial. This is a chart that shows lines designed in a semi-circle. If a person looking at this chart has a perfect vision, all the lines will be clear to him or her but if that person suffers from astigmatism, he or she will only see a few clear lines.
A keratometer is used to measure the light from your cornea. It is a device that measures the overall radius of your cornea’s curve. The results will let your eye doctor know the degree of abnormality or the curvature.
#4. Corneal Topography
Another test that will show the curve and the shape of your cornea is a corneal topography test.
According to the American Optometric Association, children are encouraged to take eye tests when they reach 6 months, 3 years old, before they get into first grade and then every 2 years following that. Children who are at high risk of astigmatism are advised to take eye tests yearly. For adults, the recommended every 2 years is actually enough but if you suffer from health conditions such as diabetes you are required to take eye tests more often.
How Does Astigmatism Manifest?
What are the signs of astigmatism? The most common signs that indicate astigmatism include blurred vision whether near or far, frequent headaches, when a person squints way too often, eye strain and having difficulty driving during night time. Although these signs are not conclusive to astigmatism, you still need to have your eyes checked.
How Is This Treated and What Lens Can Correct It?
Mild astigmatism doesn’t need any treatment. Nevertheless, the ideal treatment for astigmatism is the use of corrective lenses.
Corrective lenses are effective in fixing vision problems associated with astigmatism because it bends incoming light. This feature in the lens will correct wrong refraction. In effect, the images will be clear because they will be appropriately projected to your retina. Corrective lenses can be designed via contact lenses or through glasses. Lenses designed for this specific eye abnormality will have to have a spherical power. This is designed for individuals who are near or far sighted. It must also have a lens power to fix astigmatism and an axis designation to describe the position of the cylinder correction.