One-hundred-fourty-eight normal, sighted eyes, treated for myopia with argon fluoride 193-mm excimer laser, were analyzed 18 months postoperatively with respect to stability of refraction. Mean refraction 18 months after surgery was -0.32 D (+/- SD 0.89), a figure which was not significantly different from mean refractions at 12 and 15 months postoperatively. Also at 18 months, 86% of the eyes had an uncorrected visual acuity greater-than-or-equal-to 20/40, and 82% of the eyes were within 1.00 D of intended refraction (i. e. emmetropia). These percentages, which are directly related to postoperative refraction, are similar to those noted at 12 months after surgery. Although it may be too early to conclude that the 18-month refractions represent a definitive predictor of future refraction, the numerous similarities between the 12- and 18-months data presented in this study tend to suggest stability of refraction 18 months after excimer laser photorefractive keratectomy for myopia.
