The Effect of Excimer Laser PRK Using Single-pass Multizone Technique on High Myopia

ABSTRACT

Corneal haze and myopic regression are not uncommon complications following photorefractive keratectomy(PRK). To avoid these problems, multipass multizone technique has been introduced. However, it is quite difficult to coincide the center of the each ablation zone during the procedure and needs to take longer operation time. Single-pass multizone software was replaced by Summit technology(USA). The current study evaluates the clinical results of single-pass multizone PRK for high myopia. We performed PRK using single-pass multizone technique on 48 eyes of 44 patients for the treatment of high myopia. Preoperative spherical equivalent refractions ranged from -8.00 diopters((D) to -16.00 D (mean+/-SD, -11.01 +/- 1.84 D). Mean postoperative refraction was +1.12 +/- 1.20 D at one month, -0.42 +/- 1.24 D at six months, and -0.92 +/- 1.09 D at one year. The percentage of patients achieving correction within +/-2.0 D was 79.2% at one month, 85.4% at six months, and 88.2% at one year postoperatively. There was no serious complications after surgery. This study provides evidence that single-pass multizone PRK is a safe, simple and fairly predictable method for high myopic correction. But further studies are needed to confirm the longer-term stability.