
Acrysof® Toric 

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Routine cataract surgery with a traditional monofocal implant does not necessarily eliminate the need for glasses for distance, near, intermediate vision, or all three. In other words, patients usually need to use glasses after cataract surgery with a traditional implant (but with those glasses, the vision should be clearer and patients should have fewer symptoms than before). One of the factors that can limit the sharpness of uncorrected vision (without glasses) after cataract surgery, is astigmatism. What is astigmatism? Astigmatism is an uneven curvature of the cornea. Like nearsightedness or farsightedness, astigmatism can make the vision blurry. It's easier to understand this concept by first asking the question, what does it mean to not have astigmatism? In simplistic terms, if there is no astigmatism, the cornea of the eye (see Tour of the eye) is shaped like a baseball cut in half. The curvature or steepness of the resulting half-dome is the same regardless of the direction from which it is viewed (imagine a miniature version of you walking around the circumference of this half-dome). Compare this to a cornea which is similar to a football cut in half lengthwise (in the long direction, through both pointy ends). The curvature of the cornea in the long direction (along the seams) is not as steep as along the short direction. Such a cornea focuses light, not at a single point, but at 2 points. Someone who has uncorrected astigmatism may see images that are fuzzy and doubled.
For patients who do have a significant amount of corneal astigmatism, getting a a toric implant at the time of cataract surgery would, in most cases, allow for good distance vision without glasses, though "cheaters" would still be necessary for reading or intermediate viewing. If such a patient just received a traditional lens implant, glasses would likely be necessary for distance, reading, and intermediate vision, usually bifocals, trifocals, or progressives.
One type of toric implant is the Acrysof® Toric IOL. In FDA studies, 60% of patients who received an Acrysof® Toric IOL in one eye achieved spectacle freedom for distance vision, compared to less than 40% of patients who received a non-toric or traditional monofocal IOL in one eye. Of the patients who received the Acrysof® Toric in both eyes, 97% achieved spectacle freedom for distance vision, compared to only 50% of patients who received non-toric or traditional monofocal IOLs in both eyes. In short, the Acrysof® Toric implant can reduce the need for glasses after cataract surgery in patients with astigmatism. |