Astigmatic keratotomy to correct preexisting astigmatism in cataract patients

We evaluated three general strategies for dealing with astigmatism control following phacoemulsification with posterior chamber intraocular lens surgery: (1) a neutral wound closure to minimize surgically induced cylinder; (2) wound revision techniques to minimize residual postoperative cylinder; (3) astigmatic keratotomy incisions to treat preexisting astigmatism. With the neutral wound closure, mean postoperative keratometric cylinder averaged less than 1 diopter (D). In the presence of moderate preoperative astigmatism (1.0 D to 1.9 D), the wound revision technique tended to undercorrect, while the astigmatic keratotomy tended to overcorrect. However, the keratotomy procedure resulted in less postoperative cylinder. For cases with substantial preoperative astigmatism (greater than or equal to 2 D), the astigmatic keratotomy groups corrected more of the preoperative cylinder, which resulted in a greater proportion of cases with less than 1 D of postoperative cylinder and a smaller proportion with more than 2 D. Results suggest that astigmatic keratotomy is a useful adjunct to correct preexisting astigmatism in cataract patients. However, this procedure as any incisional refractive surgery technique has a certain amount of inherent biological variability.