Photorefractive Keratectomy for Myopia of -8.00 to -24.00 Diopters

BACKGROUND: Sixty-eight highly myopic eyes (mean refraction, -11.17 diopters [D]; range, -8.00 D to -24.00 D) were treated with excimer laser photorefractive keratectomy and followed 1 year. METHODS: A 193 nm Meditec excimer laser was used with a 5.0-mm ablation zone without peripheral taper. All patients were followed during a period of at least 1 year. All patients had a complete ophthalmological examination including videokeratography and documentation of haze. RESULTS: After 1 year, uncorrected visual acuity was 20/20 or better in eight (13%) and 20/40 or better in 48% of eyes; 42% of eyes had a refraction within +0.50 D, 74% within +/-1.00 D, and 90% within +/-2.00 D of the planned correction. The eyes that needed only a single treatment obtained the best results. In 30% of eyes, two treatments were necessary in order to obtain acceptable results. A decrease of spectacle-corrected visual acuity, caused by the laser treatment, was exceptional, probably transient, and increased when a second treatment was necessary. Subjective complaints were present in four of 68 eyes. Eyes with clinically significant regression had more and longer lasting haze. CONCLUSION: Excimer laser photorefractive keratectomy for myopia of -8.00 D and more give less predictable results than those achieved for less than -8.00 D. Two treatments improve the outcome but cause more loss of spectacle-corrected visual acuity.