摘要
目的 :利用ORBSCAN Ⅱ和角膜超声测厚法探讨准分子激光原位角膜磨镶术后 2～ 3年的角膜前、后表面和角膜厚度的变化 ,说明LASIK的相对安全性。方法 :随机选择 2～ 3年前在我院行LASIK的 41例患者共 81眼 ,按屈光度的不同分成三组 :Ⅰ组 :<- 6 .0D ,33眼 ;Ⅱ组 :- 6 .2 5～ -10 .0D ,31眼 ;Ⅲ组 >- 10 .2 5D ,17眼。利用ORBSCAN Ⅱ和角膜超声测厚仪检查的结果 ,比较三组角膜前、后表面高度图和角膜厚度的数据 ,进行统计学处理。结果 :角膜前表面高度图的前表面顶点距理想球面的距离 (diff值 ) :Ⅰ组 :(-0 .0 0 94± 0 .0 10 )mm ;Ⅱ组 :(- 0 .0 17± 0 .0 0 89)mm ;Ⅲ组 :(-0 .0 2 6± 0 .0 12 )mm ,三组差异有非常显著性 (P <0 .0 1) ;角膜后表面高度图的后表面顶点距理想球面的距离 (diff值 ) :Ⅰ组 :(0 .0 39± 0 .0 13)mm ;Ⅱ组 :(0 .0 5 1± 0 .0 14)mm ;Ⅲ组 :(0 .0 6 7± 0 .0 2 9)mm ,三组差异有非常显著性 (P <0 .0 1) ;角膜厚度 :Ⅰ组 :(4 5 9.6 1± 35 .97) μm ;Ⅱ组 :(4 45 .6 2± 32 .33) μm ;Ⅲ组 :(4 47.2 3± 45 .83) μm ,三组差异无显著性 (P >0 .0 5 )。 结论 :LASIK手术角膜瓣下保留 2 5 0 μm以上的角膜基质 ,相对是安全的。但对于超高度近视应持慎重态度 ,尽可能多地保留角膜基?
Objective:To conduct research using an obscan-Ⅱ and ultrasonic pachymetry to study the changes in the anterior and posterior surfaces and corneal thickness 2～3 years after laser in situ keratomileusis to prove that laser in situ keratomileusis is relatively safe.Methods:Subjects were randomly selected from a group of patients who underwent LASIK in our hospital 2～3 years ago. Subjects were divided into three groups according to their pre-operative level of myopia:Group Ⅰ:<-6.0 D,33 eyes;Group Ⅱ:-6.25～-10.0 D,31 eyes;Group Ⅲ:>-10.25 D,17 eyes. The three groups underwent examination with an orbscan-Ⅱ and ultrasonic pachymetry to map the anterior and posterior elevation on the surfaces and to measure corneal thickness. The resulting data was statistically analyzed.Results:Distance from the top point of the anterior surface in the anterior elevation map of the anterior surface of the cornea to the perfect spherical surface(diff value):Group Ⅰ:(-0.094±0.010)mm;Group Ⅱ:(-0.017±0.089)mm;Group Ⅲ:(-0.026±0.012)mm,P<0.01. Distance from the top point of the posterior surface in the posterior elevation map of the posterior surface of the cornea to the perfect spherical surface(diff value):Group Ⅰ:(0.039±0.013)mm;Group Ⅱ:(0.051±0.014)mm;Group Ⅲ:(0.067±0.029)mm,P<0.01;thickness of the cornea:Group Ⅰ:(459.61±35.97)μm;Group Ⅱ:(445.62±32.33)μm;Group Ⅲ:(447.23±45.83)μm,P>0.05.Conclusion:If more than 250 mm is preserved under the corneal cap in a LASIK procedure,the procedure is relatively safe. Caution should be exercised if a patient has high myopia;it is necessary to preserve the base material of the cornea as much as possible in this case to prevent a tapered cornea developing after LASIK surgery.
出处
《眼视光学杂志》
2002年第3期150-151,共2页
Chinese Journal of Optometry & Ophthalmology
