TIME-DELAYED, 2-STEP EXCIMER-LASER PHOTOREFRACTIVE KERATECTOMY TO CORRECT HIGH MYOPIA

BACKGROUND: Besides scarring, undercorrection is an important complication of photorefractive keratectomy in myopes over 10.00 diopters. METHODS: We performed a two-step time delayed photorefractive keratectomy with time-different ablation zone diameters in a 24-year-old female with amblyopia to correct a total myopic refraction error of - 10.75 D, In the first session, a simple myopic correction of - 6.50 D with a 5-millimeter ablation zone was performed, and 6 months later, a second myopic correction of - 4.00 D with a 6.5-millimeter ablation zone was performed. RESULTS: Four months after the second photorefractive keratectomy with an ablation zone of 6.5 mm, the refraction was + 0.75 - 2.25 x 40-degrees and stayed constant for 2 more months. After the second treatment, an initial increase in corneal haze was seen, but after 4 months, the corneal haze did not exceed the status before the second treatment. CONCLUSION: A planned two-step, time-delayed photorefractive keratectomy with a larger second ablation zone is a possible approach to overcoming the problem of undercorrection and regression in high myopia.