The Effects of Ablation Diameter on the Outcome of Excimer Laser Photorefractive Keratectomy A Prospective, Randomized, Double-Blind Study

Objective: To determine the effects of the ablation diameter on the outcome of excimer laser photorefractive keratectomy. Design: Eighty patients were randomized to either a 5.00-mm or a 6.00-mm treatment group and within these groups underwent either a −3.00-diopter (D) ora −6.00-D correction based on their preoperative refraction. A Summit Omnimed excimer laser was used throughout the study. Results: In eyes treated with a 6.00-mm-diameter ablation, the initial hyperopic shift was reduced, with significant differences at 1 week with −3.00-D corrections and at 1 and 4 weeks with −6.00-D corrections ( P P P P P P Conclusions: Treatment with 6.00-mm ablation diameters precipitated less initial overcorrection, greatly improved the predictability of photorefractive keratectomy, and was associated with a reduction in complications impairing postoperative visual performance.