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

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.

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

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.

Treatment of Near Esotropia with High AC/A Ratio

The patients with accommodative esotropia due to high AC/A(accommodative convergence/accommodation) ratio show prominent esodeviation and can not fuse without bifocals at near. The purpose of this study is to eliminate prominent near esotropia in those patients and let them fuse at near without bifocals. We performed unilateral or bilateral medial recti recti recessions according to the angle of near esotropia in 14 patients. Twelve patients showed orthophcria or small esophoria less than 12 delta. Eleven of these patients obtained solid fusion after surgery except 3-year-old patient who could not understand the stereopsis test. One patient had esophoria of 20 delta after surgery and showed gross stereopsis. The other patient recurred 27 delta of intermittent esotropia. Twelve of 13 patients(92.3%) could fuse without bifocals at near. The recession of medial rectus or recti was effective on the removal of prominent near esotropia and obtaining fusion without bifocals. Furthermore it did not disturb angle of deviation and fusion at distant. We recommend this procedure as a secure and effective treatment for near esotropia caused by high AC/A ratio.