Characterized by an irregularly shaped lens or cornea, astigmatism distorts vision and often causes headaches and eye strain.
Like nearsightedness or farsightedness, astigmatism is a refractive error. This means light rays cannot come to a single point of focus.
How can I tell if I have astigmatism?
Visual Signs That You May Be Suffering
Blurred or Distorted Vision
Because of the shape of the lens or cornea, light may focus on several points in front of or behind the retina, causing visual errors such as halos around lights.
Difficulty with Night Vision
Many people experience distorted vision at night or in low-light situations. Commonly, patients have a hard time adjusting their eyes when driving, especially when another car passes in the opposite direction.
Squinting and Headaches
Many patients find themselves squinting to compensate for blurry vision. Habitual squinting and other forms of eye strain frequently lead to chronic headaches.
Genetics and Injury Can Put You at a Higher Risk
Many cases of astigmatism are present at birth, leading researchers to believe that genetics play a part in its development. In other cases, it astigmatism could arise as the child's eye is growing.
Patients who have experienced some form of eye trauma may be at a higher risk for developing astigmatism because the injury can cause the cornea to become distorted. Additionally, a condition called keratoconus, in which the corneas take on a cone-shape, can also put you at a higher risk for developing astigmatism.
So what causes the condition?
Astigmatism is Tied to Other Refractive Errors
This occurs when the cornea is excessively curved or the eye is longer than normal. Nearsightedness can lead to astigmatism, because it disrupts the way that light is focused on the retina.
This condition is the result of too little corneal curvature. In other words, the eye is shorter than it should be. Farsightedness can cause astigmatism in a similar manner to nearsightedness, because light is not properly focused on the retina.
"Astigmatism occurs in about one in three Americans, but the common condition is easily treatable." American Academy of Ophthalmology™
Avoiding Eye Strain and Eating a Wholesome Diet Can Help
Staring at a computer or television screen for long periods of time can put a tremendous amount of strain on your eyes. Avoiding this type of activity or at the very least, taking a break periodically, can help prevent the condition.
Do Not Read in Low Light
Poor lighting causes you to strain and squint when reading, placing unnecessary stress on your eyes. Ensuring that you have adequate lighting can help preserve your vision.
A Balanced Diet
Eating a diet rich in dark, leafy vegetables, organic pasteurized eggs, black currants, and salmon can keep your eyes strong and healthy. These foods contain essential nutrients that can protect ocular function.
Testing is Done During Your Annual Eye Exam
During your routine eye exam, your doctor will test for astigmatism with the same tools and instruments used to assess other aspects of your vision. Your doctor may shine a light at your pupil and incorporate a series of corrective lenses at different strengths (known as a refraction test) to determine the presence and severity of the condition. To examine the shape of the cornea, your doctor may use a keratometer.
Your doctor may use a keratometer, which can measure the curvature of your cornea.
Each of these tests are quick, easy, and painless.
There are Multiple Treatment Options
Corrective eyeglasses can be designed to correct your exact corneal irregularity. This form of eyewear can address astigmatism at the same time as nearsightedness or farsightedness.
Many cases of astigmatism can be corrected by wearing daily contact lenses. Other cases may be solved by wearing semi-rigid contacts for several hours each day to even out the curvature of the eye.
Just as LASIK can be used to correct other refractive errors, your doctor can use an excimer laser to reshape the cornea and provide relief from visual distortion.
Photorefractive Keratectomy (PRK)
PRK is similar to a LASIK surgery, with the main difference being that your doctor will remove the outer protective layer of the cornea to sculpt the shape of the eye. This outer layer, called epithelium, will grow back naturally.
Schedule Your Next Exam
Although misshapen corneas can cause a degree of visual errors, astigmatism is very common and easily treatable. Schedule your next eye exam and ask your doctor to test for the condition. Together, you can find the best way to bring the world back into focus.