CAJ | 학술논문

目的比较不同切削量的准分子激光原位角膜磨镶术(LASIK)术后眼角膜生物力学特性及角膜变形的情况.方法选取成年新西兰白兔16只(32眼)随机分成A、B、C、D四个组.A、B、C组均行LASIK手术,使残留的基质床厚度分别为全层角膜厚度的30%、50%、70%;D组不行切削手术,作为对照组.术后6个月对兔眼行角膜地形图检查;对条状角膜在Instron试验机上进行单向拉伸和拉伸蠕变实验,用最小二乘法拟合得出不同切削量的角膜在蠕变实验中的弹性系数.结果术后6个月,角膜地形图检测结果显示,A组角膜切削区的中央部较周边膨隆;B、C组均未发现角膜膨隆和圆锥角膜.与对照组比较,A、B组LASIK术后角膜的弹性模量有统计学意义(P<0.05),C组无统计学意义.结论 LASIK术后6个月,角膜刚度系数随角膜切削量的增加而减小,角膜抗拉能力也随之减小,但使剩余的基质床厚度保留至全层角膜厚度的50%时是否会造成继发性圆锥角膜尚需进一步的研究.
목적 비교불동절삭량적준분자격광원위각막마양술(LASIK)술후안각막생물역학특성급각막변형적정황.방법 선취성년신서란백토16지(32안)수궤분성A、B、C、D사개조.A、B、C조균행LASIK수술,사잔류적기질상후도분별위전층각막후도적30%、50%、70%;D조불행절삭수술,작위대조조.술후6개월대토안행각막지형도검사;대조상각막재Instron시험궤상진행단향랍신화랍신연변실험,용최소이승법의합득출불동절삭량적각막재연변실험중적탄성계수.결과 술후6개월,각막지형도검측결과현시,A조각막절삭구적중앙부교주변팽륭;B、C조균미발현각막팽륭화원추각막.여대조조비교,A、B조LASIK술후각막적탄성모량유통계학의의(P<0.05),C조무통계학의의.결론 LASIK술후6개월,각막강도계수수각막절삭량적증가이감소,각막항랍능력야수지감소,단사잉여적기질상후도보류지전층각막후도적50%시시부회조성계발성원추각막상수진일보적연구.
Objective To compare the influence of residual corneal thickness on the biomechanical properties of the cornea and corneal deformation 6 months after laser in situ keratomileusis (LASIK). Methods Sixteen New Zealand white rabbits (32 eyes) were randomly divided into 4 groups. Eight eyes were analyzed in each group. LASIK was performed on the rabbits in groups A, B and C with residual corneal stroma thicknesses of 30%, 50% and 70%, respectively. The rabbits in group D were the controls. Corneal topography was analyzed 6 months after LASIK. Strips of cornea were tested for uniaxial tension and creep with an Inatron 5544. The viscoelastic coefficients of the creep experiment were plotted for the different residual corneal thicknesses using the least squares fit method and the regression and experimental curves were plotted. Results Central corneal curvature was higher than peripheral corneal curvature in the therapy areas in group A. There was no ectasia or keratoconus on the corneal topography in group B and C. The elasticity modules of the cornea for the 3 different groups that underwent LASIK and the normal group have significant differences except for group C (P>0.05). Conclusion Stiffness coefficients diminished with an increase in the depth of the incision and the anti-tensile ability of the corneas is also reduced after LASIK. Further study needs to be done on keratoconus after LASIK with a residual stroma thickness of 50% of the cornea.