The cornea around your iris and pupil is, under normal conditions, spherical. As light enters the eye, part of the job of your cornea is to focus that light, aiming it toward the retina, which is in the rear part of your eye. But what is the result when the cornea isn't exactly round? The eye cannot focus the light correctly on one focal point on your retina, and will cause your vision to be blurred. Such a condition is referred to as astigmatism.
Astigmatism is actually a fairly common vision problem, and usually comes with other vision errors that require vision correction. Astigmatism frequently occurs early in life and can cause eye fatigue, painful headaches and the tendency to squint when uncorrected. In children, it may cause obstacles in the classroom, often when it comes to reading or other visual tasks. Sufferers who work with fine details or at a computer monitor for excessive periods might find that the condition can be problematic.
Astigmatism is preliminarily diagnosed during an eye exam with an eye care professional and then fully diagnosed with an automated refraction or a retinoscopy exam, which measures the degree of astigmatism. Astigmatism is commonly fixed with contacts or eyeglasses, for those who prefer a non-invasive procedure, or refractive surgery, which changes the flow of light onto the retina to readjust the focal point.
Toric lenses are commonly prescribed for astigmatism because they permit the light to curve more in one direction than another. Regular contact lenses generally shift when you blink. But with astigmatism, the smallest movement can completely blur your sight. After you blink, toric lenses return to the same position on your eye to avoid this problem. Toric lenses are available in soft or rigid lenses.
In some cases, astigmatism can also be fixed with laser surgery, or by orthokeratology (Ortho-K), a non-surgical procedure that involves wearing rigid contacts to gradually change the shape of the cornea during the night. You should discuss your options and alternatives with your optometrist to determine what your best choice is for your needs.
For help explaining astigmatism to children, have them compare the back of two teaspoons - one circular and one oval. In the circular teaspoon, their mirror image will appear normal. In the oval one, their face will be stretched. And this is what astigmatism means for your eye; you end up viewing the world stretched out a bit.
Astigmatism changes over time, so make sure that you're regularly making appointments to see your optometrist for a proper exam. Also, make sure that your 'back-to-school' list includes taking your kids to an eye care professional. A considerable amount of your child's education (and playing) is mostly a function of their vision. You can allow your child get the most of his or her schooling with a thorough eye exam, which will pick up any visual abnormalities before they impact education, sports, or other extra-curricular activities. It's important to know that astigmatism is very treatable, and that the earlier to you begin to treat it, the better off your child will be.