Excimer Laser Photorefractive Keratectomy. 18-month Follow-Up

摘要: Purpose: This study, comprising 120 patients (follow-up, 12 to 22 months; mean, 18 months), was designed evaluate the efficacy and safety of excimer laser photorefractive keratectomy. Methods: Ablation zone diameter (4 mm), ablation rate (0.22 μm/pulse), fluence (180 mJ/cm 2 ), frequency (10 Hz) were kept constant, all used a standard topical corticosteroid regimen. Results: Overcorrection followed by regression stable refraction 4 months. At 1 year, 95% 70%, respectively, undergoing −2.00 diopters (D) −3.00 D corrections 40% 20% those −6.00 −7.00 within ±1.00 intended refraction. Anterior stromal "haze", maximal at 6 months diminishing thereafter, detected in 110 (92%). However, best-corrected Snellen visual acuity reduced only (18%). Good correlation existed between haze ( r = 0.68). Night "halos", due relatively small 4-mm zone, reported 94 (78%) early postoperative period, and, (10%) declined treatment other eye because persistence this problem. Conclusion: Marked individual variation found after low myopia, predictability is "fair", procedure safe. The authors conclude that keratectomy holds considerable promise for refractive surgery future.