What Is Astigmatism?

Astigmatism is a condition where the cornea has an irregular shape that causes problems with vision. The cornea, the clear covering of the lens and iris, serves as a protection to the eye and helps transmit light thru the eye. The cornea is normally spherical in shape, but those with astigmatism may have their cornea more oval shaped. This oval shaping causes light to scatter instead of focusing to a single point as it passes thru the cornea and results in blurred vision.

If you've ever looked at the images produced but those wavy mirrors at carnivals, you'll have some idea of how astigmatism can distort your vision.

Astigmatism is characterized by distortions in your field of vision, often noted as the blurring of lines. Astigmatism is also a common cause of eyestrain and headaches, especially with prolonged reading or lengthy sessions at the computer. Astigmatism causes blurring of your vision at all distances, so objects close up and even those far away will be blurred. Often present at birth, astigmatism affects many people, although not all cases are severe enough to require corrective treatment.

Astigmatism is usually discovered during routine eye exams when your doctor checks your eye's refraction and visual acuity using standard eye charts. Refraction is the ability to properly focus light rays on the retina and can be measured in a number of ways. Some doctors will ask a series of questions and conduct a visual acuity test, while others will use a keratoscope or keratometer to measure the curvature and shape of your cornea to determine your degree of astigmatism.

Astigmatism can be corrected thru the use of corrective lenses, involving either glasses or contact lenses. Astigmatism can also be corrected with refractive eye surgery.

Corrective Lenses for Astigmatism

Corrective lenses are a conservative method of dealing with astigmatism. Glasses and contact lenses are able to counter the effects of the irregularly shaped cornea and provide vision considerable improvement.

Ortho-K is an alte
ative method that uses special contact lenses that actually reshape the cornea. These special lenses are worn only at night and they gradually reshape the cornea by applying pressure in the right way.

LASIK Surgery for Astigmatism

A common misconception is that LASIK eye surgery doesn't apply to astigmatism, but that's false.

LASIK eye surgery is by far the most commonly selected procedure for refractive eye surgery. During the LASIK procedure, a small incision creates a corneal flap and an excimer laser is used to reshape the cornea. The excimer laser is different from other lasers in that it doesn't produce heat. Once the procedure has been completed, the corneal flap is repositioned normally and the healing process begins. Most people can notice quite an improvement in vision immediately upon completion of the procedure.

LASIK surgery is quick and painless, usually being performed on an out-patient basis. In most cases, you'll notice an immediate improvement in vision and the procedure is virtually painless, taking only a few minutes to complete.