Astigmatic keratotomy for post-keratoplasty astigmatism

PURPOSE: To assess astigmatic keratotomy as a means of managing post-keratoplasty astigmatism in the era of excimer laser refractive surgery. SETTING: Moorfields Eye Hospital, London, England. METHODS: Fifty paired arcuate keratotomies were performed with refractive and topographic guidance. Refraction, uncorrected visual acuity, best corrected visual acuity, and visual acuity with the patient's preferred correction were measured before and after surgery. RESULTS: The median follow-up was 34 months. The mean cylinder was 9.13 diopters (D) preoperatively and 4.85 D postoperatively. The mean spherical equivalent refraction was -4.21 D preoperatively and -4.26 D postoperatively. The amount of cylinder reduction was correlated with the amount of pre-existing cylinder (P<.001). Thirty eyes (60%) gained and 1 eye (2%) lost Snellen acuity with preferred correction. In the remaining 19 eyes (38%), there was no change in acuity with preferred correction. The mean change in visual acuity with preferred correction was a gain of 1.5 Snellen lines. Three patients intolerant of spectacles or contact lenses before surgery became tolerant. Ten patients (20%) previously unsuitable for laser in situ keratomileusis (LASIK) because of high cylindrical error went on to have LASIK. CONCLUSIONS: Astigmatic keratotomy remains a useful, safe, relatively simple surgical procedure for treating post-keratoplasty astigmatism. Reduction in cylinder was correlated with pre-existing cylinder. Vision with preferred correction was improved in 60% of cases. High astigmatism reduced to a level at which more definitive refractive surgery such as LASIK became feasible.