Mastropasqua Leonardo, Nubile Mario, Ciancaglini Marco, Toto Lisa, Ballone Enzo
Department of Medicine and Aging Science and Section of Ophthalmology, University of Chieti, Italy.
J Refract Surg. 2004 Sep-Oct;20(5):422-31. doi: 10.3928/1081-597X-20040901-03.
To study refractive results and aberrometric changes in myopic patients treated with wavefront-guided photorefractive keratectomy (PRK) in comparison with standard PRK.
Sixty eyes of 60 patients with myopic astigmatism were randomly divided into two groups. Group 1 included 30 eyes (mean spherical equivalent refraction -4.39 +/- 1.31 D; range -2.50 to -6.50 D) treated with wavefront-guided PRK using the WASCA workstation and the Asclepion Meditec flying spot MEL 70 excimer laser. Group 2 had 30 eyes (mean spherical equivalent refraction -4.33 +/- 1.22 D; range -2.50 to -6.50 D) that underwent conventional PRK using the same laser, and served as the control group. Wavefront analysis of high order aberrations was performed before and 6 months after surgery.
Postoperatively, wavefront error increased in both groups (5.0-mm wavefront aperture diameter). Six months after surgery, the eyes that received the WASCA ablation had a smaller increase in root-mean-square (RMS; 70% of increment) compared to the conventional PRK group (139% of increment) (P<.001). In the standard PRK group, all aberrations notably increased; in the wavefront-guided PRK group there was a smaller increase of trefoil and spherical aberrations (P<.001) and a decrease of coma aberrations (P<.001). The smaller increase of wavefront error in the wavefront-guided PRK group compared to the standard PRK group was more evident when preoperative RMS values were higher than 0.4 microm (P<.01). The visual parameters (spherical equivalent refraction, uncorrected and best spectacle-corrected visual acuity) did not show significant differences between the two groups.
Wavefront-guided PRK induced a smaller increase of postoperative wavefront-error compared to conventional PRK, particularly in patients with higher preoperative higher order aberrations.
比较波前引导的准分子原位角膜磨镶术（PRK）与标准PRK治疗近视患者后的屈光结果和像差变化。
将60例近视散光患者的60只眼随机分为两组。第1组包括30只眼（平均等效球镜度数-4.39±1.31 D；范围-2.50至-6.50 D），使用WASCA工作站和Asclepion Meditec飞点MEL 70准分子激光进行波前引导的PRK治疗。第2组有30只眼（平均等效球镜度数-4.33±1.22 D；范围-2.50至-6.50 D），使用同一激光进行传统PRK，作为对照组。在手术前和手术后6个月进行高阶像差的波前分析。
术后两组的波前误差均增加（波前孔径直径5.0 mm）。术后6个月，接受WASCA消融的眼睛与传统PRK组相比，均方根（RMS；增量的70%）增加较小（增量的139%）（P<0.001）。在标准PRK组中，所有像差均显著增加；在波前引导的PRK组中，三叶草像差和球差增加较小（P<0.001），彗差像差减少（P<0.001）。当术前RMS值高于0.4微米时，波前引导的PRK组与标准PRK组相比，波前误差增加较小更为明显（P<0.01）。两组的视觉参数（等效球镜度数、未矫正和最佳矫正视力）无显著差异。
与传统PRK相比，波前引导的PRK术后波前误差增加较小，尤其是术前高阶像差较高的患者。
