Excimer photorefractive keratectomy for myopia

Autor: Michael R. Deitz, Felix N. Sabates, Larry W. Piebenga, Camille S. Matta, Joseph Tauber, John W. Irvine
Rok vydání: 1993
Předmět:
Zdroj: Ophthalmology. 100(9)
ISSN: 0161-6420
Popis: Purpose: To study the safety, effectiveness, predictability, and stability of excimer laser photorefractive keratectomy (PRK) in 133 normally sighted eyes. Methods: An excimer laser was used with a fluence of 160 mJ/cm 2 at a frequency of 5 Hz and an ablation zone of 5.0 mm. The effects of nitrogen purge at surgery and postoperative steroids were evaluated. Results: No significant complications occurred in any patient. After an initial overcorrection, the refraction stabilized. The average results obtained at 6 months were maintained on successive examinations to 36 months. Analysis of their visual acuity in groups IIA, IIB, and III indicates that results at 6 months are predictive of final results at 1 to 3 years ( P 0.9). In myopia (1.00–6.00 diopters [D]) treated with the excimer laser, there was a trend toward improvement in results over the course of the study. In 60% in group IIA, 58% in group IIB, 71% in group III, and 88% in group III no nitrogen (no N 2 ), ±1 D was obtained. For 20/40 or better uncorrected visual acuity, the outcome was 70% for group IIA, 67% for group IIB, 75% for group III, and 100% for group III no N 2 . Significant improvement was noted without nitrogen purge. No significant improvement was observed from steroid treatment as used. Conclusion: In reducing myopia, PRK appears to be safe and effective. The results obtained are reasonably predictable and stable after 6 months. As more refinements are introduced, this procedure could become one of the most promising in refractive surgery.
Databáze: OpenAIRE