Astigmatism

The smaller astigmatically neutral incisions we now routinely make enable us to deal more accurately during cataract surgery with pre-existing astigmatism.
Relaxing incisions into the steep meridian of the cornea (arcuate keratotomy or limbal relaxing incisions) are useful for reducing up to 5 diopters of pre-existing astigmatism.

Another way of correcting pre-existing astigmatism during cataract surgery is to use a new “toric” intraocular lens into which the astigmatism correction has already been incorporated. This lens has to be placed in the proper meridian.
For patients with even greater astigmatism, limbal relaxing incisions can be made several weeks before cataract surgery, followed by the insertion of a toric intraocular lens to treat the residual astigmatism. In addition, LASIK (laser in-situ keratomileusis) can be used to pre-treat corneal astigmatism and can be combined with limbal relaxing incisions, toric intraocular lenses or a combination of all three.