Effect of Excimer Laser Radial Kentotomy on the Correction of Myopia and Astigmatism: Report 2

Choi, Tae Hun; Lee, Ha Bum

Abstract

The term Excimer is a contraction of "Excited dimer", and it is emitting light produced in the far-ultraviolet portion of the spectrum and has a wave length of 193 nm produced by an argon fluoride. It ablate corneal tissue through photochemical Iaser tissue interaction without thermal damage. We performed the radial keratotomy with argon fluoride excimer laser (MEL50, MEDITEC,W.GERMANY) and treated 71 eyes of myopia and myopic astigmatism from February 1989 to February 1990. All eyes were followed up about six months to 1 yr or over 1 yr and the results were as follows: 1) The mean flattening by skiascopy was 2.32 diopters(D), that is 1.42 D of low myopia, 2.07 D of moderate myopia, 2.54 D of high myopia. By Keratometry, the mean flattening was 1.67 D, that is 2.0 D of low myopia, 1.9 D of moderate myopia, 1.52 D of high myopia. In the correction for the best visual acuity, spectacle diopter was decreased average 2.19 D, that is 1.75 D of low myopia, 2.32 D of moderate myopia, 2.15 D of high myopia respectively. After Ruiz operation, the astigmatic flattening in 4 cases were 2.0, 3.0, 2.0 and 1.0 D respectively. 2) The uncorrected visual acuity after surgery was 20/40 or better in 32% of the entire eye group, that is, 60% of low myopia, 60% of moderate myopia and 12% of high myopia.