正常人眼角膜前表面光学质量MTF影响因素的探讨  

Exploration of the influencing factors of optical quality by determining MTF for anterior corneal surface in normal human

作　　者：郑艳珍[1,2] 邱岩[1] 翟国光[1] 李耀宇[1] 

机构地区：[1]北京军区总医院眼科,中国北京市100700 [2]山西医科大学研究生院,中国山西省太原市030001

出　　处：《国际眼科杂志》2012年第5期851-855,共5页International Eye Science

摘　　要：目的:探讨角膜前表面不同像差的RMS值对MTF值的影响。方法:患者200例400眼用sirius3D角膜地形图分析仪检查,取3,5,7mm角膜光学区校正低阶球差后的MTF曲线,以及总像差、总高阶像差、彗差、三叶草、球差的RMS值。记录空间频率为5,10,15,20,25,30cpd时的MTF值及垂直彗差和水平彗差的zernike系数。结果:角膜前表面总像差在3,5,7mm角膜光学区时RMS值都与MTF值各空间频率统计学相关,高阶像差在3mm角膜光学区时与垂直和水平子午线的MTF值均相关,在较大光学区时(5,7mm)主要影响水平子午线的MTF值。角膜前表面彗差及三叶草像差主要影响水平子午线方位的MTF值,且在较小光学区(3,5mm)较明显。角膜前表面球差在角膜光学区为3mm时与垂直和水平子午线方位的MTF值均统计学相关。四叶草和次级散光在角膜光学区为3mm和7mm时与垂直和水平方位的MTF值有较好相关,在5mm光学区时与水平子午线方位MTF值相关。角膜彗差的方位与不同方位MTF值之间无相关性。结论:角膜前表面水平子午线方位的MTF值与高阶像差明显相关,MTF可以全面、客观的评价角膜的光学质量。AIM： To explore the root mean square（RMS） value of the anterior corneal surface aberration on the modulation transfer function（MTF） values. METHODS： Four hundred eyes from 200 patients were examined under sirius 3D corneal topography system, MTF curve at 3,5,7mm corneal optical zone after correcting the low-order spherical aberration and the total aberration and total higher order aberration, coma, trefoil aberration, spherical aberration RMS values were taken . MTF values at the spatial frequency of 5,10,15,20,25,30 cpd and zernike coefficient of vertical and horizontal coma were recorded. RESULTS： Anterior corneal surface RMS in 3,5,7mm corneal optical zone were statistically related at different spatial frequency with the MTF value, higher-order RMS in 3mm corneal optical zone were related with the MTF both vertical and horizontal meridian. The larger optical zone （5,7mm） mainly affected the MTF of horizontal meridian.Coma and trefoil aberrations for the anterior corneal surface mainly affected the the MTF of horizontal meridian, and more evident in smaller optical zone （3.5mm）. Spherical aberration in 3mm corneal optical zone was statistically related with the MTF of vertical and horizontal meridian.Clover and secondary astigmatism in 3mm and 7mm corneal optical zone and the MTF of vertical and horizontal meridian had a good correlation and they had correlation with the MTF of horizontal meridian in 5mm corneal optical zone. No correlation was between the corneal coma position and MTF of different orientation. CONCLUSION： The MTF of anterior corneal surface at horizontal meridian are greatly related with higher order aberrations.The MTF can objectively evaluate the optical quality of anterior cornea .

关 键 词：调制传递函数 均方根值 光学质量 

分 类 号：R770.4[医药卫生—眼科]