Excimer laser photorefractive keratectomy for high myopia

One hundred and thirty-three eyes of 103 patients had photorefractive keratectomy with a slit scan mode excimer laser for myopia ranging from -6.00 to -22.00 diopters (D). The epithelium was removed with 20% ethanol, and the ablation was done with a tapered profile surrounding the optical zone. Patients were divided into two groups based on preoperative myopia: Group A, -6.00 D to -12.00 D (88 eyes); Group B, -12.50 D to -22.00 D (45 eyes). In Group A, mean preoperative refraction was -9.59 +/- 1.79 D. Mean postoperative refraction was -0.29 +/- 1.47 D at one month, -0.85 +/- 1.68 D at three months, -1.17 +/- 2.04 D at six months, and -0.56 +/- 0.74 D at one year. Anterior stromal haze was greatest at the end of the first month; it diminished thereafter. This haze did not reduce the best corrected visual acuity in any eye in Group A. Mean preoperative refraction in Group B was -14.69 +/- 5.27 D. Mean postoperative refraction was -1.34 +/- 2.02 D at one month, -0.76 +/- 2.08 D at three months, -3.88 +/- 2.32 D at six months, and -5.50 +/- 5.00 D at one year. Three eyes in Group B lost one or two lines of best corrected visual acuity as a result of severe stromal haze and epithelial scarring. Group A's results were similar to those obtained in eyes with low myopia.(ABSTRACT TRUNCATED AT 250 WORDS)