Astigmatism refers to an eye condition that prevents you from focusing properly on an object by creating a sharp image on the retina. The blurred image could be due to an irregularity of the toric curvature of either the lens or the cornea.
Essentially, there are two types of astigmatism: regular and irregular. Regular astigmatism is the more common variant, and is characterized by a defect in the crystalline lens or the cornea of a person. Irregular astigmatism on the other hand is determined by scarring of the cornea, or scattering of the crystalline lens. This type of astigmatism cannot be corrected by regular corrective lenses of prescription glasses. Instead, people who have the condition are generally prescribed contact lenses.
Diagnosing and treating astigmatism
There are only three known treatment mechanisms for the condition: refractive surgery, spectacles and toric or hard contact lenses. The treatment is not the most difficult part for the people who suffer from the condition. Diagnosing astigmatism is slightly harder. Blurred vision could amount to any number of eye conditions. The condition can even be asymptomatic, making it difficult to point out sometimes, even for trained doctors.
Patients with high levels of astigmatism show signs of blurred vision, asthenopia, frequent headaches, squinting and fatigue. According to a research , astigmatism can lead to migraine attacks.
Tests that help diagnose astigmatism
Ophthalmologists use various tests to check whether a patient has astigmatism or not. Not only do these tests determine whether someone has the condition, but they also measure the extent to which the variation is. During an eye exam, your optometrist will ask you to look at a Snellen chart. If your visual acuity is generally less than expected, it is likely that you suffer from a similar condition.
A keratometer will help determine the curvature of the lens or cornea, and will thereby identify the flattest and steepest meridians of the front surface of the cornea. Based on this knowledge, your optometrist will prescribe spectacles or contact lenses with the suitable power.
For a better projection of the shape of the cornea, your eye doctor could use corneal topography instruments. The representation will help decide how much astigmatism actually affects your vision. Regular checkups with your eye doctor can help assess whether you suffer from such conditions before it starts affecting your daily life.