Seven Year Results of Excimer Laser Photore fractive Keratecto my for Myopia.

Shin, Jeong Hwan; Park, Jong Seok; Lee, Hae Young

Original Article

Journal of the Korean Ophthalmological Society 2000;41(6):1310-1316.
Published online June 1, 2000.

Seven Year Results of Excimer Laser Photore fractive Keratecto my for Myopia.

Jeong Hwan Shin, Jong Seok Park, Hae Young Lee

Department of Ophthalmology, Seoul Red Cross Hospital, Seoul, Korea.

엑시머 레이저를 이용한 근시교정술의 7 년 경과관찰결과

신정환(Jeong Hwan Shin),박종석(Jong Seok Park),이해영(Hae Young Lee)

Abstract

To evaluate the long term efficacy of excimer laser photorefractive kerate-ctomy (PRK)for myopia, 37 eyes of 20 patients were observed for 7 years after PRK.The patients were divided into three groups according to preop-erative myopia :group 1 with diopters between -2.00 and -5.75, group 2with diopters between -6.00 and -9.75, group 3 with myopia over -10.0 diopter.During the follow up period, 6 months, 1 year, 2 years and 7 years, refractive error, uncorrected and best corrected visual acuity and corneal opacity were examined. Mean refractive errors seven years after PRK were changed significantly. In group 1 and group 3, long-term regression occured between 2 and 7 years (paired t test:p=0.01, p=0.01, respectively).In group 2, long-term regression occured between 1 and 7 years (p=0.02).At 7 years, in group 1, 92%of eyes, in group 2, 69%of eyes, and in group 3, 20%of eyes achieved uncorrected visual acuity of 0.5 or better.The group 3 showed a trend toward greater regression. With these results we thought that excimer PRK was effective for mild-to-moderate myopia, while less effective for high myopia.Despite the effi-cacy, we believe that slow myopic regression can continue up to 7 years and further follow-up is essential to assess long-term effect.

Key Words: Excimer laser;Myopic regression;Photorefractive keratectomy;Seven year clinical results