准分子激光治疗高度和超高度近视的远期疗效

A comparative study on excimer laser photorefractive keratectomy and laser in situ keratomileusis in correction of high and severe myopia

目的:比较准分子激光屈光性角膜切削术(PRK)和激光原位角膜磨镶术(LASIK)治疗高度和超高度近视的远期临床效果及其影响疗效的因素。方法:高度近视眼163例(294眼),其中PRK组84例(139眼),平均等效球镜屈光度-8.68±2.08D,LASIK组79例(155眼),平均等效球镜-9.17±2.92D。按术前屈光度分2组,Ⅰ组-6.25～-10.00D,Ⅱ组≥-10.00D,随访2a。结果:2a时,裸眼视力≥0.5者,Ⅰ组中PRK占89.5%,LASIK占96.8%;Ⅱ组中PRK占35.3%,LASIK占83.9%。裸眼视力≥1.0者,Ⅰ组中PRK为51.4%,LASIK为80.6%;Ⅱ组中PRK为2.9%,LASIK为46.8%。术后屈光度在预期矫正屈光度±1.00D范围以内者:Ⅰ组中PRK为62.8%,LASIK为88.2%;Ⅱ组中PRK为17.6%,LASIK为61.3%。角膜上皮下混浊(Haze)发生率,PRK组0级53.2%,0.5级25.3%,1级13.0%,2级8.6%。其中Ⅰ组发生率为39.0%,Ⅱ组发生率为70.5%。LASIK组均无上皮下或层间混浊发生。术后2a的等效球镜屈光度(Y)PRK组与术前等效球镜(X1雪,角膜屈光力(X 2)建立多元回归方程为Y =-8.645+0.444X1+0.265X 2(P <0.001)。LASIK组与术前等效球镜(X 1)、术中角膜切削深度(X 3)建立多元回归方程Y =-0.703+0.52X 1+0.0437X 3(P <0.001)。结论:准分子激光治疗高度和超高度近视眼的临床效果LASIK术式较PRK术式具有明显的优势。

AIM: To compare the therapeutic effects and effective factors of excimer laser photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) in the correction of high and severe myopia. · METHODS: A total of 163 cases (294 eyes) were observed, in which 84 cases (139 eyes) with high and severe myopia (-6.25 to -16.50 diopers) underwent photorefractive keratectomy and Laser in situ kerotomileusis was performed on 79 cases (155 eyes) (-6.25 to -17.75 diopers) using VISX 20/20 excimer laser. These eyes were divided into two groups on the basis of preoperative refraction (groupⅠ, -6.25- -10.0D; groupⅡ, ≥-10.0D) and the follow-up was 2 years. · RESULTS: At two-year follow-up visit, in groupⅠ, 89.5% of eye treated with PRK and 96.8% with LASIK achieved an uncorrected visual acuity of 20/40 or better, 35.3% and 83.9% in groupⅡ; In groupⅠ, 51.4% of eye treated with PRK and 80.6% with LASIK achieved an uncorrected visual acuity of 20/20 or better, 2.9% and 46.8% in groupⅡ. The rate of corneal haze were 39.05% in groupⅠwith PRK and 70.53% in groupⅡ with PRK. The regression equation for postoperative refraction was figured out as Y=-8.645+0.444X1+0.265X2(P <0.001) in PRK and Y=-0.703+0.52X1+0.0437X3(P <0.001) in LASIK. X1=preoperative refraction (D), X2=preoperative corneal dioptic power (D), X3=corneal ablation (μm). · CONCLUSION: The clinical results of LASIK for correction of high and severe myopia are more significant than those of PRK. It is influenced by factors such as preoperative refraction, corneal diopter power in PRK and corneal ablation in LASIK.·