Astigmatism Correction

Now, cataract patients with cataracts and astigmatism have another option — the AcrySof Toric Lens, which corrects for both conditions simultaneously. Implanted in the eye to restore vision after cataract surgery, the AcrySof Toric lens implant is an artificial lens specifically designed to provide both spherical and astigmatic correction. We invite you to call to have your questions answered or to make an appointment: (262) 637-0500.

About Astigmatism:
Whether myopic or hyperopic, most eyes have corneal astigmatism to some degree. Corneal astigmatism means that the front part of your eye, the clear window you look through, is not perfectly round. Instead of being spherical like a basketball, an astigmatic cornea is slightly flattened, more oval in shape like a football, with one side steeper than the other (as illustrated below).

Correction of astigmatism

astigmatism effect on sightBecause the astigmatic cornea is curved more (steeper) in one direction than the other, light entering the eye is refracted differently as it passes through these different areas. This causes light to come into focus at several different points on the back of the eye, rather than ideally coming into focus at just one point (note the illustration, right).

Depending on the direction and the amount of astigmatism, vision through an astigmatic cornea will be affected in various ways. The illustration (below) gives a broad example of the visual effects, depending on the overall direction of the curve:

vision with different types of astigmatism

Limbal Relaxing Incisions For Astigmatism Correction:
Following cataract surgery, eye surgeons commonly prescribe glasses or contact lenses to correct astigmatism. However, some surgeons will treat corneal astigmatism at the time of cataract surgery through the use of "limbal relaxing incisions" (LRI's). This involves making tiny incisions in the cornea to "relax" or flatten the steeper meridian, thereby causing the corneal curvature to become more rounded, reducing astigmatism.

lRI incisionsThese long, thin incisions are placed at the very edge of the cornea (known as the corneal limbus) on the steepest meridian, and differ in number and length according to the amount of astigmatism. Relaxing incisions generally do not eliminate corneal astigmatism completely, but rather reduce it to an acceptable level. Because the cornea is living tissue, there may be "over-response" or "under-response" to these incisions. Seldom is corneal astigmatism completely resolved; however, a significant reduction in your astigmatism produces a more satisfactory uncorrected visual result.

Some patients with extreme amounts of astigmatism may still require the addition of limbal relaxing incisions to correct astigmatism after cataract surgery with the AcrySof toric lens. For the patients, with unusually high amounts of astigmatism, implanting the toric lens means that less corneal surgery in the form of a limbal relaxing incision is needed to achieve the same amount of correction.

In the future, the AcrySof Toric Lens Implant will be available in higher powers of astigmatic correction so that even very high amounts of corneal astigmatism can be corrected without the addition of limbal relaxing incisions.

Make your appointment today with The Eye Centers of Racine & Kenosha, to see if the AcrySof Toric lens for the correction of astigmatism is right for you. If you would like further information, please call our office at: (262) 637-0500.

The Eye Centers of Racine and Kenosha provide the on-line information above solely for educational and communication purposes. Nothing contained on the site should be misconstrued as personal medical advice. None of the information published on the Eye Center website is intended to replace, supplement, or augment a medical visit with or medical advice from an eye care professional concerning the medical care of the viewer / user of the site. The Eye Centers of Racine and Kenosha disclaim any and all liability for injury or other damages resulting from the use of any information obtained from this website.