Photorefractive keratectomy for myopia: preliminary results in 147 eyes

Excimer photorefractive keratectomy (PRK) was performed on 100 consecutive patients (147 eyes) for the correction of myopia. The follow up period ranged from 3 to 16 months (mean, 8). Preoperative myopia ranged from -1.75 to -8.75 D (mean -3.90 D). Patients were divided into three groups for analysis based upon their degree of preoperative myopia: mild (< or = 2.90 D), moderate (-3.00 to -5.90 D), and severe (> or = -6.00 D). Uncorrected visual acuity was 20/40 or better in 88.4% (130/147) overall; 97% of mild, 91% of moderate, and 68% of severely myopic patients. Preoperative astigmatism remained the primary cause of reduced uncorrected visual acuity. Postoperatively, 68% of patients overall had a spherical equivalent refraction within +/- 1.00 D. The majority of treated corneas had trace (53%) to mild (29%) subepithelial haze. One patient with severe myopia developed significant subepithelial opacification postoperatively with partial regression and loss of one line of best spectacle corrected visual acuity.