Three-year results of radial keratotomy

We complied three-year and longer follow-up data on 198 consecutive radial keratotomy surgeries performed by one of us (H.S.). Follow-up was obtained on 138 (70%) of these eyes. Results were compared with previously published two-year results. The mean spherical equivalent before surgery was -4.3 diopters, the average keratometry value was 44.11 D, and 75% of the eyes had an uncorrected distance acuity of 20/400 or more. The average change in the spherical equivalent was 3.74 D for eyes examined at three years, compared with 3.71 D for eyes examined at 18 months. Average keratometry value was 40.96 D after three years, compared with 41.16 D at 18 months. Uncorrected visual acuity was at least 20/40 in 73% of eyes examined after three years, as opposed to 72% at 18 months. For eyes examined at both 18 months and three years, the increase in spherical equivalent of 0.17 D was statistically significant, as was the decrease in average keratometry value of 0.20 D. Uncorrected visual acuity results were stable between 18 months and three years.