i.Profiler和iTrace波前像差仪测量健康人眼波前像差的一致性

目的：:评价i.Profiler和iTrace波前像差仪测量健康人眼波前像差的一致性,分析角膜高阶像差与瞳孔直径的相关性。方法：:系列病例研究。连续纳入健康青年受检者96例（96眼）,采用i.Profiler和iTrace进行波前像差测量,参数包括2～6 mm瞳孔直径下角膜和3、5 mm瞳孔直径下全眼高阶像差,包括总高...     

波前像差仪测量近视患者低阶像差的临床研究

目的:通过波前像差仪与自动验光仪、综合验光仪3种方法测量近视患者屈光状态结果的对比观察,探讨波前像差仪对低阶像差测量的准确性。方法:随机选取2005-06/2005-09来我院进行LASIK术前检查的近视患者67例100眼,分别应用波前像差仪、自动验光仪、综合验光仪对其球镜度数、柱镜度数、散光轴向测量后进行统计分析、比较。结果:波前像差仪、自动验光仪、综合验光仪3种方法测得的球镜度数分别为-6.18±2.77,-5.80±2.80,-5.88±2.72D;柱镜度数分别为-0.73±0.57,-0.75±0.59,-0.72±0.56D;散光轴向中位数分别为66.00°,45.50°,27.50°,四分位数间距分别为162.75°￣11.25°,160.00°～4.25°,161.00°～5.00°;等效球镜度分别为-6.55±2.90,-6.17±2.91,-6.24±2.81D;统计学上均无显著性差异。结论:波前像差仪在准确测量眼高阶像差的同时,能够准确地测量近视患者的低阶像差。     

不同像差分析设备对白内障患者角膜高阶像差测量的比较

目的: 比较新一代屈光分析仪OPD-ScanⅢ、扫频源眼前节光学相干断层扫描分析仪CASIA2与像差仪iTrace、三维眼前节分析仪Pentacam测量白内障患者角膜总高阶像差(tHOA)、角膜球面像差(SA)的差异性和一致性。方法: 系列病例研究。选取2021年5—8月在天津医科大学眼科医院白内障科行超声乳化白内障吸除联合人工晶状体植入术的白内障患者123例(123眼)。所有患者均采用iTrace、Pentacam、OPD-ScanⅢ和CASIA2测量角膜参数, 记录以角膜顶点为中心4 mm直径下的角膜tHOA及6 mm直径下的角膜SA的均方根(RMS)值。4种设备间测量结果的差异性分析采用两因素方差分析或Friedman检验, 相关性分析采用Person或Spearman相关分析。不同设备间测量结果的一致性评价采用Bland-Altman分析。结果: 4种设备测量角膜tHOA总体差异有统计学意义(Z=134.79, P<0.001)。两两比较显示, CASIA2和Pentacam测得的角膜tHOA差异无统计学意义, 且均高于OPD-ScanⅢ和iTrace(均P<0.0...     

自适应光学视觉模拟器测量波前像差的重复性及与OPD-Scan Ⅲ的一致性研究

目的：评价自适应光学视觉模拟器(VAO)测量全眼高阶像差的重复性及与OPD-Scan Ⅲ测量全眼高阶像差的一致性。

方法：采用横断面研究方法。纳入2023-08/09在成都东区爱尔眼科医院屈光科就诊的近视患者204例204眼(均取右眼数据)。由同一位操作熟练的检查者分别使用两种设备进行检查,使用VAO测量4.5 mm瞳孔直径下3-6阶的高阶像差,VAO和OPD-Scan Ⅲ测量3-6 mm瞳孔直径下全眼总高阶像差(tHOA)、球差(SA)、彗差(Coma)和三叶草像差(Trefoil),评估VAO测量全眼像差的重复性及两种设备的一致性。

结果：VAO测量全眼的高阶像差均显示较高的重复性(0.767≤ICC≤0.941、S_w<0.01 μm、TRT<0.1 μm)。4-6 mm瞳孔直径下VAO与OPD-Scan Ⅲ的Coma测量值无差异(P>0.05),其余瞳孔直径下全眼总高阶像差的测量值均有差异(均P<0.05)。VAO与OPD-Scan Ⅲ的3 mm瞳孔直径下各阶像差以及4、5 mm瞳孔直径下的SA、4 mm瞳孔直径下的Coma测量值的95%LoA<0.1,显示一致性较好,其余瞳孔直径下的像差测量值的95%LoA>0.1,显示一致性较差,两种设备3 mm(r=0.218-0.317,P<0.01)、4 mm(r=0.406-0.672,P<0.01)、5 mm(r=0.538-0.839,P<0.01; r=0.030-0.109,P>0.01)以及6 mm(r=0.369-0.766,P<0.01)瞳孔直径下高阶像差测量值差异较大。

结论：VAO测量3-6 mm瞳孔直径下全眼高阶像差结果时具有良好的重复性,但VAO与OPD-Scan Ⅲ的3-6 mm瞳孔直径下的全眼高阶像差测量值存在差异性,一致性较差,临床应用不可互换。     

近视散光患者角膜形态对高阶像差的影响

目的 探讨近视散光患者高阶像差的分布特点及角膜形态对其的影响.方法 用wavescan wavefront system波前像差仪对LASIK术前281例（434眼）近视散光患者进行客观测量,用TMS-4角膜地形图仪获得角膜表面规则指数（surface regularity index,SRI）、角膜表面不对称指数（surface asymmetry index,SAI）以及角膜表面形态.对屈光度、SRI和SAI与高阶像差作相关分析,将患者分别按角膜形态分为5组,对各组间的高阶像差的均方根值（root mean square,RMS）作秩和检验.结果 6.0 mm瞳孔直径下的总高阶像差（root mean square of higher order aberrations,RMSh）的均方根值为（0.286±0.098）μm,从3阶至6阶大致呈递减趋势,其中以3阶彗差、三叶草和4阶球差的均数最大.屈光力和SRI与RMSh没有显著的相关性,SAI与RMSh呈正相关,Pearson相关系数为0.161,P值为0.001.SAI值对高阶像差的影响较SRI值大,尤其是SRI值较低的患者,RMSh值随SAI的增高而增大,主要表现为3阶彗差和4阶球差的增大.角膜形态为不规则形和不对称领结形时高阶像差最大,主要表现为三叶草和3阶彗差的增大.结论 6.0 mm瞳孔直径时,最主要的高阶像差是3阶彗差、三叶草和4阶球差.角膜形态为不规则形和不对称领结形时高阶像差最大.SAI对高阶像差的影响比SRI大.     

角膜波前引导的LASIK治疗低中度近视角膜高阶像差的临床观察

目的:比较角膜波前像差引导下的准分子激光原位角膜磨镶术(laser in situkeratomileusi,LASIK)和常规的LASIK对低中度近视角膜高阶像差的影响。方法:采用前瞻性非随机对比研究,选取6mo内连续的低中度近视患者32例58眼实施常规LASIK(A组,其中低度近视24眼,中度近视34眼),34例52眼实施角膜波前引导下的个性化LASIK(B组,其中低度近视23眼,中度近视29眼)。所有手术均使用德国Schwind公司Esiris第九代准分子激光治疗仪和Carriazo Pendular钟摆式角膜板层刀,使用4.2.0版本的Optikon keratron Scout2000角膜地形图对两组患者在术前和术后3mo进行6mm瞳孔直径时角膜高阶像差检查。结果:两组病例角膜球差和均方根均高于术前。A组低度近视术后高阶像差增加量依次为均方根0.236μm、彗差0.146μm、球差0.139μm和三叶差0.054μm,中度近视高阶像差增加量依次为均方根0.367μm、球差0.284μm、彗差0.177μm和三叶差0.021μm。B组低度近视高阶像差增加量依次为球差0.127μm、均方根0.088μm、三叶差0.051μm、和彗差0.042μm,中度近视高阶像差增加量依次为均方根0.175μm、球差0.162μm、彗差0.027μm和三叶差0.024μm;两组病例术后3mo裸眼视力非常接近.同样条件下低中度近视角膜波前像差引导下的个性化LASIK切削的深度较常规LASIK深。结论:角膜波前像差引导下的低中度近视LASIK较常规LASIK角膜高阶像差影响少。     

近视眼角膜前表面形态与角膜高阶像差的相关分析

目的 探讨近视眼角膜前表面形态(角膜曲率、高度、非球面性)与角膜高阶像差的相关关系.方法 横断面研究.近视患者57例(57眼),球镜度-1.50～-6.00D,平均(-3.88±1.12)D,柱镜度0～-3.50 D,平均(-0.59±0.58)D,应用Pentacam眼前节分析仪,获取角膜表面变异系数(ISV)、角膜高度的非对称指数(IHA)、非球面系数(Q值)及角膜前表面像差,应用Pearson相关分析ISV、IHA和Q值与角膜高阶像差的相关关系.结果 ISV与角膜垂直彗差(Z3-1)、水平彗差(Z3+1)均呈正相关(r=0.389,P=0.003;r=0.594,P＜0.001),与角膜球差(Z40)呈负相关(r=-0.400,P=0.002);ISV与角膜的三阶像差(S3)呈正相关(r=0.683.P＜0.001),与角膜的四阶像差(S4)呈负相关(r=-0.373,P=0.004).IHA与Z3-1、S3呈正相关(r=0.446,P＜0.001;r=0.445,P＜0.001).Q值与Z40、S4呈正相关(r=0.849,P＜0.001;r=0.761,P＜0.001),与角膜的五阶像差(S5)呈负相关(r=0.280,P=0.035).结论 角膜表面曲率变异越大,角膜的三阶像差越大.角膜表面高度上下越不对称,角膜垂直彗差越大.Q值越大,即角膜形状越偏向扁椭圆形,角膜球差越大.     

波前像差仪与综合验光仪测量近视屈光度的对比研究

目的通过波前像差仪和综合验光仪测量近视屈光度的对比观察,探讨波前像差仪测量近视屈光度的准确性。方法回顾性分析2010年7月至2011年7月在我院行近视眼矫正术术前常规行综合验光检查并行波前像差检查的患者586例(1160只眼),年龄18～40岁。按其综合验光屈光度分为轻度组(0～-3.00 DS),中度组(>-3.00 D～-6.00 D),高度组(>-6.00 D以上)分别应用综合验光仪和波前像差仪检查其球镜度、柱镜度和散光轴位,将其结果进行统计分析。结果轻度近视组综合验光与波前像差仪球镜检查结果分别为(-1.83±0.76)和(-1.88±0.77),二者差异无统计学意义(P>0.05);中度组分别为(-4.47±0.75)和(-4.38±0.99),二者差异无统计学意义(P>0.05);高度组分别为(-7.04±0.86)和(-7.16±0.88)二者差异无统计学意义(P>0.05)。散光综合验光与波前像差检查结果分别为(-0.63±0.63)和(-0.69±0.50)二者差异无统计学意义(P>0.05)。散光轴位综合验光与波前像差检查结果分别为(129.76±62.95)和(125.76±64.05)二者差异无统计学意义(P>0.05)。结论波前像差仪在准确测量眼的高阶像差的同时能准确地测量近视患者的低阶像差,可以很好的反映整个眼球屈光系统的异常。     

近视儿童角膜生物力学参数与角膜高阶像差的相关性研究

目的:应用可视化角膜生物力学分析仪(Corvis ST)测量轻中度近视儿童的角膜生物力学参数与角膜高阶像差(HOAs)的相关性。方法:横断面研究。连续收集2021-04/07在天津医科大学眼科医院视光中心就诊的儿童近视患者255例的病例资料,均取右眼进行分析。应用Corvis ST测量角膜生物力学参数;应用Pentacam三维眼前节分析仪测量并计算角膜总高阶像差(RMSh)、三阶像差(RMS3)、四阶像差(RMS4)。结果:RMS3与第2次压平时间(A2T)呈正相关关系(r=0.175,P=0.009),与眼轴长度(AL)呈负相关关系(r=-0.155,P=0.014);RMS4与最大压陷时反向曲率半径(HCR)呈负相关关系(r=-0.165,P=0.009);RMSh与HCR、AL呈负相关关系(r=-0.152,P=0.037;r=-0.175,P=0.005)。结论:近视儿童角膜生物力学参数与角膜高阶像差间存在相关性,硬度较高、抗变形能力较强的角膜,RMS3、RMS4、RMSh较小。     

中老年白内障患者中角膜高阶波前像差与眼轴长度相关性变化

目的调查我国中老年白内障患者角膜高阶波前像差分布的特点,探讨眼轴长度是否对角膜高阶波前像差产生影响,为白内障手术非球面人工晶状体的选择提供参考。方法前瞻性临床研究。使用i Trace视觉功能分析仪测量319例319只优势眼的角膜前表面高阶像差,使用IOL Master测量眼轴长度,并按眼轴长度(AL)分为短眼轴组、正视及轻度近视组、高度近视组3组。记录6 mm瞳孔直径下的总高阶像差(HOAs)、彗差(coma aberration)、球差(spherical aberration)、三叶草像差(trefoil aberraition)的均方根值(RMS)。分析角膜总高阶像差、彗差、球差、三叶草像差与眼轴长度的关系。结果短眼轴组HOAs平均值为(0.586±0.593)μm,正视及轻度近视组HOAs平均值为(0.428±0.320)μm,高度近视组HOAs平均值为(0.680±0.518)μm,正视及轻度近视组及高度近视组与短眼轴组HOAs比较无明显差异,正视及轻度近视组与高度近视组HOAs差异有统计学意义(u=-0.840,P=0.401;u=-1.845,P=0.065;u=-3.185,P=0.001);短眼轴组彗差平均值为(0.184±0.148)μm,正视及轻度近视组彗差平均值为(0.158±0.111)μm,高度近视组彗差平均值为(0.265±0.216)μm,短眼轴组三叶草像差平均值为(0.177±0.140)μm,正视及轻度近视组三叶草像差平均值为(0.155±0.102)μm,高度近视组三叶草像差平均值为(0.299±0.256)μm,短眼轴组球差平均值为(0.030±0.140)μm,正视及轻度近视组球差平均值为(0.010±0.119)μm,高度近视组球差平均值为(0.025±0.099)μm,3组间彗差、三叶草像差的差异均有统计学意义(F=12.321,F=20.515,P=0.000),3组间球差的差异无统计学意义(F=0.911,P=0.403)。结论研究表明我国中老年白内障患者中不同眼轴长度分组的瞳孔中央6 mm直径的角膜总高阶像差、彗差及三叶草像差存在着一定的差异,当AL≥25.00 mm时,总高阶像差、彗差及三叶草像差明显增大,而在不同眼轴长度分组中球差未发现明显差异。角膜球差具有较大个体差异性且未发现与眼轴有任何相关性,手术前角膜球差的精准测量是非球面人工晶状体个性化选择的必要步骤。     

光路追踪型、动态视网膜镜型与Hartmann-Shack型像差仪的临床比较研究

目的 探讨基于光路追踪、动态视网膜镜以及Hartmann-Shack原理的3种像差仪对波阵面像差测量的重复性与差异性.方法 一致性研究.选取3种不同类型的像差仪--光路追踪型(iTrace)、动态视网膜镜型(OPD-Scan)以及Hartmann-Shack(WASCA)像差仪分别对45例(86只眼)研究对象进行像差测量,对所测球镜柱镜值,总高阶像差、球差、彗差值进行统计学分析.本研究中对测量数据进行正态性及方差齐性检验后,采用配伍组设计的方差分析(ANOVA),组间两两比较采用Tukey分析检验.不同仪器间像差测量差值与等效球镜值均有较好的相关性研究采用Pearson相关性分析.结果 3种仪器的总高阶像差、球差、彗差均方根测量值均有较好的重复性.等效球镜值小于-6.00 D者,3种仪器所测量等效球镜值、总高阶像差均方根值之间差异无统计学意义.主觉验光等效球镜值大于等于-6.00 D者中,iTrace所测量的球镜值、柱镜值与主觉验光、OPD及WASCA像差仪测茸结果之间差异存在统计学意义(P<0.01),iTrace所测总高阶像差与彗差均方根值高于另两种像差仪(P<0.01),且该组中iTrace与OPD、WASCA像差仪的总高阶像差测鼍差值分别与等效球镜值之间存在部分相关性(r=-0.418,-0.399;P<0.01).结论 3种不同类型的波阵面像差仪各自的测量重复性好,但对相同眼的测量结果并不一致,这可能与各仪器的设计原理不同有关.     

Correlation between corneal and total wavefront aberrations in myopic eyes

PURPOSE: Corneal topography data expressed as corneal aberrations are frequently used to report corneal laser surgery results. However, the optical image quality depends on all optical elements of the eye, including the human lens. We investigated correlations between corneal and total wavefront aberrations and the relevance of corneal aberrations for representing the optical quality of the total eye. METHODS: Thirty-three eyes of 22 myopic patients were measured using a corneal topography system and a Tscherning-type wavefront analyzer. Pupils were dilated to at least 6 mm in diameter. All measurements were centered with respect to the line of sight. Corneal and total wavefront aberrations were calculated up to the 6th Zernike order in the same reference plane. RESULTS: Statistically significant correlations (P<.05) between corneal and total wavefront aberrations were found for astigmatism (C3,C5) and all 3rd Zernike order coefficients such as coma (C7,C8). No statistically significant correlations were found for 4th, 5th, or 6th order Zernike coefficients. On average, all Zernike coefficients for corneal aberrations were larger than the Zernike coefficients for total wavefront aberrations. CONCLUSIONS: Due to the lack of correlation between corneal and total wavefront aberrations in most of the higher order aberrations, measurement of corneal aberrations are of limited use for representation of the optical quality of the human eye, especially after corneal laser surgery. Corneal aberrations and optical elements within the eye are optically balanced. As a consequence, ideal customized ablations must take both corneal and total wavefront aberrations into consideration.     

Comparison of higher-order wavefront aberrations with 3 aberrometers

PURPOSE: To evaluate the agreement of higher-order aberrations (HOAs) between aberrometers based on the Hartmann-Shack wavefront technology. SETTING: Department of Ophthalmology, Tri-Service General Hospital, Taipei, Taiwan. METHODS: Three clinical aberrometers WaveScan (Visx Inc.), LADARWave (Alcon Inc.), and Zywave (Bausch & Lomb Inc.) were used to measure HOAs in 34 cycloplegic eyes in 17 subjects. All the measurements in each subject were performed in 1 visit to reduce the impact of biologic fluctuation of HOAs. Each device was operated by an independent experienced operator, and the operators were blind to the data obtained from the other aberrometers. Root mean square (RMS) of coma, spherical aberration, and total 3rd- and 4th-order HOAs were compared between any 2 devices by a paired t test. RESULTS: WaveScan had the lowest mean RMS, whereas Zywave reported the highest mean RMS for any HOAs. The coefficients of variation were similar between any 2 devices. Paired t tests of RMS yielded a P value <.01 in 9 of 12 comparisons. In general, the largest discrepancies of HOA measures were between WaveScan and Zywave, and similar data were found between LADARWave and WaveScan. More than 80% of the absolute difference of HOA RMS between LADARWave and WaveScan, 50% to 78% between LADARWave and Zywave, and 38% to 59% between WaveScan and Zywave were within +/-0.1 microm. CONCLUSIONS: Significant discrepancies in HOA measurements were found among the 3 popular aberrometers. The HOA RMS data were closer between LADARWave and WaveScan, and HOA RMS by Zywave was generally higher than the other 2 devices. The 3 devices had comparable measurement variation.     

Higher order aberrations in normal eyes measured with three different aberrometers

PURPOSE: To assess the repeatability of measurements of higher order aberrations using three different aberrometers and to compare higher order aberration measurements between optical path difference (OPD) scanning and the Hartmann-Shack method. METHODS: Wavefront aberration data obtained using the NIDEK OPD-Scan, Bausch & Lomb Zywave wavefront aberrometer, and VISX CustomVue wavefront analyzer were compared. A total of 19 subjects were included in the study. The repeatability in each machine was assessed by calculating the difference between measurements and the mean of three consecutive measurements in the same eye. Subsequent analysis of the distribution of these differences yields the mean difference, the standard deviation of the differences, and the 95% confidence interval for repeated measurements, also termed the "repeatability coefficient". RESULTS: Repeatability errors in all three machines were found to be low, suggesting that all three machines are reliable in their repeated measurements. Significant differences were demonstrated between OPD scanning and Hartmann-Shack aberrometers. All three machines showed statistically significant differences in several higher order aberration parameters when compared to each other. CONCLUSIONS: The three different aberrometers provided repeatable measurements but statistical differences were noted in the measurement of higher order aberrations when comparing the machines. No instrument was superior over the other and all three were reliable.     

Repeatability of corneal first-surface wavefront aberrations measured with Pentacam corneal topography

PURPOSE: To assess the repeatability of corneal wavefront aberrations derived from Pentacam (Oculus) corneal topography. SETTING: Flinders Eye Centre, Flinders Medical Centre, Bedford Park, South Australia, Australia. METHODS: Forty-five normal participants and 10 participants with keratoconus were tested. Intraobserver and interobserver repeatability was determined using 4 observers within and between sessions. Topographical maps were exported to external software, and corneal first-surface wavefront aberrations were calculated using a 10th-order Zernike expansion over a 6.0 mm optical zone. Repeatability was determined with Bland-Altman limits of agreement and expressed as the coefficient of repeatability (COR). RESULTS: Initial data showed high wavefront aberrations in normal participants and poor repeatability. Topographical maps showed extrapolated topography in zones without data acquisition; maps with less than 6.0 mm of complete data were excluded in the final analysis. The mean wavefront aberrations for normal participants remained high, but repeatability improved. The COR relative to the magnitude of wavefront aberrations was high (average 100%) across all modal pairs and orders, although best for total higher-order root mean square. Participants with keratoconus had higher magnitude wavefront aberrations and poorer repeatability but similar COR to average wavefront aberration ratios. Examination of raw elevation data showed poor repeatability. CONCLUSIONS: Wavefront aberrations calculated from Pentacam corneal topography were large in magnitude, and reliability was poor, largely due to variability in corneal elevation data. Intraobserver and interobserver reliability within and between sessions was comparable. The Pentacam was not reliable in measuring corneal wavefront aberrations.     

近视性屈光参差的波前像差研究

目的 探讨利用波前像差仪评估近视性屈光参差患者双眼的波前像差的差异.方法 选择2009年8月至2010年2月在广西视光中心验光配镜的近视性屈光参差患者60例(120眼).使用美国AMO公司的WaveScan波前像差仪采集每位患者双眼的波前像差数据.依据屈光度高低,将屈光参差患者双眼分为等效球镜为(-4.81±1.79)D的高屈光度组和等效球镜为(-2.44±1.78)D的低屈光度组.比较2组视模糊效果、总高阶像差、高阶像差百分比、彗差、三叶草像差、球差等指标的差异.结果 高屈光度组与低屈光度组的视模糊效果分别为(4.89±1.59)D、(2.78±1.72)D;总高阶像差分别为(0.38±0.15)μm、(0.38±0.15)μ,m;高阶像差百分比分别为(5.13±2.34)%、(13.39±12.30)%;彗差分别为(0.21±0.14)μm、(0.19±0.11)μm;三叶草像差分别为(0.16±0.10)μm、(0.17±0.12)μm;球差分别为(0.11±0.16)μm、(0.13±0.19)μm.其中,2组间在视模糊效果、高阶像差百分比2项指标上差异有统计学意义(均为P＜0.01),其余4项指标比较差异均无统计学意义(均为P＞0.05).结论 近视性屈光参差患者双眼高阶像差相似,但高阶像差百分比存在明显差异,这可能是近视性屈光参差发展的一个潜在危险因素.     

Epi-LASIK对近视眼高阶像差的影响

目的:探讨微型角膜刀准分子激光上皮瓣下角膜磨镶术(Epi-LASIK)对近视眼波前像差,尤其是高阶像差的影响。方法:应用Custom VueTM波前像差仪采集31例(62眼)行Epi-LASIK手术的近视患者的术前及术后1,6mo的波前像差,对所得的数据进行统计学分析。结果:Epi-LASIK术前的波前像差的分布以低阶像差占优势,为(90.12±1.02)%,高阶像差占(9.88±2.03)%。术后1mo高阶像差显著增加,整体高阶像差及各级高阶像差与术前比差异有显著性(P<0.01),高阶像差占(59.24±2.14)%,低阶像差占(40.76±3.06)%,高阶像差整体平均增加2.52倍,以二次彗差增加最多,达3.03倍,以二次球差增加其次,达2.84倍。术后6mo高阶像差占(51.74±3.08)%,低阶像差占(48.26±4.21)%。与术前相比,整体高阶像差差异仍有显著性(P<0.01),二次彗差和二次球差比术前仍有显著增加(P<0.01),但优势高阶像差彗差和球差逐渐恢复到术前水平,差异无显著性(P>0.05)。与术后1mo相比,高阶像差均有所减小,差异有显著性(P<0.01)。术前近视度数与术后各时期的整体高阶像差呈正相关,差异有显著性(P<0.01)。结论:常规Epi-LASIK术后高阶像差比术前明显增大,以二次彗差和二次球差为最显著,随着时间的推移有所减小,但不能恢复术前水平。术前近视度数越高,术后高阶像差越大。     

Changes in corneal wavefront aberrations with aging.

PURPOSE: To investigate whether corneal wavefront aberrations vary with aging. METHODS: One hundred two eyes of 102 normal subjects were evaluated with videokeratography. The data were decomposed using Taylor and Zernike polynomials to calculate the monochromatic aberrations of the cornea for both small (3-mm) and large (7-mm) pupils. RESULTS. For a 3-mm pupil, the amount of total aberrations (Spearman rank correlation coefficient r(s) = 0.145; P = 0.103) and spherical-like aberrations (r(s) = -0.068; P = 0.448) did not change with aging, whereas comalike aberrations exhibited a weak but statistically significant correlation with age (r(s) = 0.256; P = 0.004). For a 7-mm pupil, total aberrations (r(s) = 0.552; P < 0.001) and comalike aberrations (r(s) = 0.561; P < 0.001) significantly increased with aging, but spherical-like aberrations showed no age-related changes (r(s) = 0.124; P = 0.166). Simulated pupillary dilation from 3 mm to 7 mm caused a 38.0+/-28.5-fold increase in the total aberrations, and the extent of increases significantly correlated with age (r(s) = 0.354; P < 0.001). Pupillary dilation influenced the comalike aberrations more in the older subjects than in the younger subjects (r(s) = 0.243; P = 0.006), but such age dependence was not found for spherical-like aberrations (r(s) = 0.141; P = 0.115). CONCLUSIONS. Comalike aberrations of the cornea correlate with age, implying that the corneas become less symmetrical along with aging. Spherical-like aberrations do not vary significantly with aging. Pupillary dilation markedly increases wavefront aberrations, and those effects are more prominent in older subjects than in younger subjects.     

Higher-order wavefront aberrations in corneal refractive therapy.

PURPOSE: To assess the changes in higher-order (third through sixth) ocular wavefront aberrations produced by Corneal Refractive Therapy (CRT; Paragon Vision Sciences, Mesa, AZ). METHODS: Eighteen eyes of nine myopic subjects were fit with CRT contact lenses. Baseline subjective spherical refraction ranged from -2.25 to -6.00 D (mean +/- SD, -3.33 +/- 1.26 D), and baseline logarithm of the minimum angle of resolution (logMAR) best-corrected visual acuity was -0.13 +/- 0.06 (20/15 Snellen equivalent). Whole-eye ocular wavefront aberrations were measured using a previously validated Shack-Hartmann aberrometer. Measurements were taken at baseline and 1 month after treatment initiation. Nine measurements per dilated subject were taken and averaged. Zernike coefficients were used to calculate the third-, fourth-, fifth-, and sixth-order root-mean-square values for each eye for both 3- and 6-mm pupil sizes, and aberrations were averaged and compared with prior baseline readings. RESULTS: The mean (+/-SD) myopia reduction was 3.08 +/- 0.93 D, resulting in a subjective refraction of -0.22 +/- 0.38 D after 1 month of lens wear. Both logMAR uncorrected visual acuity (-0.07 +/- 0.18; 20/15- Snellen equivalent) and best-corrected visual acuity (-0.14 +/- 0.09) after CRT wear were not significantly different from baseline logMAR best-corrected visual acuity (paired two-tailed t-test; p = 0.41 and 0.65, respectively). Whole-eye aberrations showed a statistically significant increase in higher-order aberrations for both 3-mm (factor of 2.66; p = 0.01) and 6-mm pupils (factor of 2.50; p = 0.005). Each individual higher-order aberration also increased, ranging from a factor of 2.01 to 3.20 for 3-mm pupil sizes and 2.52 to 2.98 for 6-mm pupil sizes. Spherical-like aberrations (S4 and S6) increased by a factor of 1.79 for 3-mm pupil sizes and 2.42 for 6-mm pupil sizes. The Zernike coefficient most affected by CRT was spherical aberration (Z40), which increased from 0.084 +/- 0.16 to 0.39 +/- 0.16 microm (p = 0.0002) for 6-mm pupils. CONCLUSIONS: Use of current CRT lenses for the reduction of myopia increased higher-order wavefront aberrations and spherical aberration (Z40) in particular.