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.     

119例近视眼患者波前像差分析

目的 分析近视患者波前像差的分布特点及波前像差检查的应用价值.设计回顾性病例系列.研究对象近视患者119例（238眼）.方法 采用Nidek OPD-Scan ARK 10000对近视患者进行波前像差检测,得到各像差成分均方根（RMS）值和高阶像差图形.主要指标五阶及五阶以下像差的RMS值.结果 波前像差由低阶到高阶RMS值呈递减趋势;低阶像差、总体高阶像差和第3阶像差均在不同球镜度之间存在显著性差异;裸眼视力与低阶像差呈负相关关系;球镜度数与低阶像差、总体高阶像差和第3阶像差存在正相关关系;高阶像差的图形以三叶草型为主.结论 近视患者波前像差以低阶像差、总体高阶像差及三阶像差为主.高阶像差的图形存在较大的个体差异.波前像差能精确、快速、敏感地反映人眼屈光系统的光学特点,可望为角膜屈光手术的个体化切削提供准确指导.     

成人正视眼与近视眼角膜高阶像差分布的研究

目的 研究角膜前表面高阶像差在成人正视眼与单纯近视和复性近视散光眼的分布.方法 选取年龄在18～50岁拟做LASIK手术的患者,单纯近视眼患者149例292眼,按球镜屈光度分成低度、中度、高度3组;复性近视散光患者351例(691眼),按柱镜屈光度分成低度、中度、高度3组.年龄在18～50岁成人正视眼60例108眼作为对照组,要求电脑验光球镜屈光度在±1.00 D以内,柱镜在-1.00 D以内,且裸眼视力在1.0以上.角膜波前像差分析采用OPTIKON 2000 Keratron Scout分析仪.角膜波前像差分析均为6 mm瞳孔直径.结果 无论成人正视眼还是近视眼均存在高阶像差,6 mm瞳孔直径均以三阶和四阶为主,高阶像差RMS值呈递减趋势,阶数越高,像差越小.正视眼组存在较大的彗差,而单纯近视眼组彗差较小,2组比较差异有显著统计学意义(P<0.001);正视眼组球差较小,而单纯近视眼组球差较大,2组比较差异有统计学意义(P<0.05).正视眼和近视散光眼2组均存在较大彗差,但2组比较无统计学意义(P>0.05),而在其他像差Z(3,±3)、Z(4,0)、Z(4,±2)、Z(4,±4)、Z(5,±1)、Z(5,±3)、Z(5,±5)、RMSg 2组比较差异均有统计学意义(P<0.05).单纯近视眼和近视散光眼在各像差Z(3,±1)、Z(3,±3)、Z(4,0)、Z(4,±2)、Z(4,±4)、Z(5,±1)、Z(5,±3)、Z(5,±5)及RMSg比较差异均有统计学意义(P<0.05).球差和球镜度数呈正相关(r=-0 501,P<0.001),其他高阶像差和球镜度数无关,但在-6 00 D以上的近视眼中,彗差和球镜度数呈正相关(r=-0 409,P<0.005).球差和散光度无关(P>0.5),其他像差均和散光度有关(P<0.05),随着散光度的增加,各像差的RMS值均增加.结论 无论正视眼还是近视眼都存在角膜高阶像差,均以三阶和四阶像差为主,两者之间存在差异;球镜度对球差影响更大,散光对彗差影响更明显,对其他像差也有一定的影响,散光更多是由角膜前表面引起的.     

准分子激光原位角膜磨镶术和准分子激光角膜上皮瓣下磨镶术对近视患者高阶像差的影响

目的:探讨波阵面像差引导的准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)和准分子激光角膜上皮瓣下磨镶术(laser epithel ialkeratomileusis,LASEK)对近视眼高阶像差的影响,并作对比分析。方法:波阵面像差引导的LASIK手术(IK组)共18例36眼和波阵面像差引导的LASEK手术(EK组)共10例20眼,分别于术前和术后10d;1,3mo测量高阶像差,用t检验分析手术前后高阶像差的变化和不同手术方式对高阶像差影响。结果:两组术后总高阶像差RMS值均较术前增加,以三、四阶像差增加为主,五、六阶像差和水平彗差无明显变化;两组的球差均较术前增加,两组间无差异;术后EK组的总高阶像差、三阶、四阶像差和垂直彗差均小于IK组。结论:波阵面像差引导的LASIK和LASEK都会使眼高阶像差不同程度的增加,LASEK的增加幅度小于LASIK。     

双面准分子激光原位角膜磨镶术治疗高度近视眼术后高阶像差分析

目的 比较双面准分子激光原位角膜磨镶术(both side lasik,BSL)和准分子激光原位角膜磨镶术(Laser in situ keratomileusis,lasik)治疗高度近视眼术后高阶像差的变化.方法 选择BSL和lasik两种术式对高度近视眼手术治疗61例,122只眼.其中,BSL手术30例,60只眼;lasik手术31例,62只眼.使用NIDEK公司生产的OPD-SCAN波前像差分析议,测量术前和术后一周、一个月和三个月暗室6～7 mm自然瞳孔直径的波前像差.结果 1 BSL和lasik两组术前总高阶像差、C7、C8和C12均方根值(RMS值)比较,均P＞0.05,差异无统计学意义.2术后一周、一个月和三个月时BSL和lasik两组的总高阶像差、C7、C8和C12RMS值均较术前差异有统计学意义(P＜0.01).3.术后一周、一个月和三个月BSL和lasik两组之间总高阶像差、C7、C8和C12RMS值比较,P值均＞0.05差异无统计学意义.结论 BSL和lasik两种手术方法治疗高度近视眼,术后高阶像差增加幅度相近似.     

泪膜破坏对不同近视人群波前像差的影响

目的 探讨泪膜破坏对于不同性别、年龄、屈光度的近视人群的波前像差检测结果的影响.方法 应用Schirmer原理设计的波前像差仪检测54例(108眼)近视患者在6 mm瞳孔下的波前像差,然后每名患者均以先右眼后左眼的顺序滴用0.4﹪的盐酸奥布卡因1次,每只眼分别于用药后10 s重复测量6 mm瞳孔下的波前像差,并根据屈光度、性别、年龄、散光度数进行分组比较用药前后波前像差的改变有否差异,结果均以均方根值(root mean square,RMS)来表示.结果 泪膜破坏后所有眼的高阶像差RMS均增加,其中,三阶散光、三阶彗差、总高阶像差和四阶、七阶像差RMS的用药前后比较,差异有统计学意义(P＜0.05).低中度近视组与高度近视组用药前后比较,三阶彗差、总高阶像差和四阶、六阶像差RMS增加值差异有统计学意义(P＜0.05).散光组与无散光组比较,三阶彗差、三阶散光、总高阶像差和五阶像差RMS增加值差异有统计学意义(P＜0.05).中年组与青年组比较,三阶彗差、三阶散光和七阶像差RMS增加值差异有统计学意义(P＜0.05).男性组及女性组用药前后比较,高阶像差的增加值差异无统计学意义(P＞0.05).结论 泪膜破坏后高阶像差RMS值增加,在高度近视散光的中年近视人群中这种改变更加明显.(中国眼耳鼻喉科杂志,2007,7:359-361)     

近视眼角膜前表面点扩散函数的斯特列尔比特征分析

目的 探讨不同瞳孔直径下近视眼角膜前表面总像差的斯特列尔比(SR)与总高阶像差SR的正常值及其与调制传递函数(MTF)的关系.方法 横断面研究.应用Sirius 3D角膜地形图仪对200例(400眼)进行角膜前表面总像差的SR和总高阶像差的SR检查.采用单因素方差分析比较角膜前表面总像差的SR和总高阶像差的SR分别在不同瞳孔直径下(3.0、5.0、6.0、7.0 mm)的差异.Pearson相关分析研究二者分别与对应的均方根值(RMS)的相关性,以及总像差SR与对应的MTF值的之间的相关性.结果 在不同瞳孔直径下(3.0、5.0、6.0、7.0mm)角膜前表面总像差100' SR值为(0.46±0.13) ～ (0.14±0.03);总高阶像差100'SR值为(0.69±0.15)～(0.17±0.04);角膜前表面总像差200'SR值为(0.45±0.13)～(0.16±0.04);总高阶像差200' SR值为(0.70±0.15) ～ (0.20±0.05),各组均逐渐变小;角膜前表面总像差SR值和总高阶像差SR值与对应的RMS值之间均存在负相关关系.当瞳孔直径小时,总像差SR值与MTF值的高频区相关性较高;而当瞳孔直径大时,总像差SR值与MTF值的低频区相关性较高.结论 近视眼角膜前表面总像差SR值和总高阶像差SR值与瞳孔直径呈负相关,并且SR值与RMS值及MTF值之间均存在一定的相关性.     

儿童近视眼高阶像差与屈光度关系的分析

目的探讨睫状肌麻痹状态下儿童近视眼高阶像差与屈光度的关系。方法前瞻性系列研究。收集在我院就诊符合纳入标准的46例（83眼）近视眼和正视眼儿童,在睫状肌麻痹状态下应用iTrace视功能分析仪进行全眼波前像差的检测,提取瞳孔直径6mm时全眼的高阶RMS值（3-5阶）、3-5阶各项Zemike系数,比较不同屈光度分组之间全眼高阶像差RMS值（3-5阶）、3-5阶各项Zemike系数的差异及近视眼组高阶像差与屈光度的关系。结果低度近视组与正视眼组比较C40差异有统计学意义（P〈0．05）;不同屈光度分组问比较,4、5阶RMS值组间差异有统计学意义,其他3-5阶各项Zernike系数、总RMS值、3阶RMS值组间差异无统计学意义（P〉0．05）;近视眼组总高阶像差与等效球镜屈光度值无相关性。结论儿童近视眼高阶像差与近视屈光度无相关性。     

波前像差引导飞秒激光制瓣LASIK术后不同范围角膜高阶像差的变化

目的比较波前像差引导飞秒激光制瓣LASIK手术前后不同直径范围角膜前、后表面总高阶像差、球差、彗差、三叶草像差变化情况。方法 应用Pentacam眼前节测量分析系统对术前及术后3～6个月行波前像差引导飞秒激光制瓣LASIK的患者24例(48眼)进行检查测量,分别获得角膜中央直径为4mm、6mm范围角膜前表面、角膜后表面、全角膜总高阶像差、球差(Z40和Z60)、彗差(Z3-1、Z3+1、Z5+1和Z5-1)以及三叶草像差(Z3+3、Z3-3、Z5+3和Z5-3)的RMS值。应用SPSS13.0统计学软件进行数据分析。结果 手术前随着测量范围的增大,除角膜前表面彗差外,角膜前、后表面其余各类像差分布均是增加的,且差异均有统计学意义(均为P<0.05)。手术后角膜中央直径4mm范围前表面彗差、三叶草增加相对明显,与术前相比均有统计学差异(均为P<0.05);后表面各类像差改变均不明显,差异均无统计学意义(均为P>0.05);全角膜各类像差均增加,与术前相比差异均有统计学意义(均为P<0.05)。手术后角膜中央直径6mm范围前表面球差、彗差、三叶草、总高阶像差均增加,与术前相比差异均有统计学意义(均为P<0.05),其中彗差增加量与其他类像差增加量相比相对较小;后表面与全角膜各眼科新进展 2014年7月 第34卷 第7期类像差均增加,与术前相比差异均有统计学意义(均为P<0.05)。手术后角膜中央6mm范围前后表面除慧差外,各类像差增加量均明显较4mm范围大,差异均有统计学意义(均为P<0.05)。手术后角膜前表面各类像差变化量均较角膜后表面各类像差变化量大。结论 波前像差引导飞秒激光制瓣LASIK手术前后、不同直径范围均以角膜前表面高阶像差变化为主,角膜后表面变化较小。手术后不同直径范围角膜前后表面各类高阶像差变化特点也不同。     

暗适应下近视患者眼高阶像差分析

目的了解暗适应下近视患者眼球高阶像差的分布,并探讨瞳孔大小(pupillarydiameter,PD)、屈光度、年龄和性别对高阶像差的影响。方法在暗室内,采用Visx公司的WaveScan波前像差仪对LASIK术前189例(338眼)近视患者进行检查,分别提取PD分别为5.0mm、5.5mm及6.0mm时的高阶像差均方根(rootmeansquare,RMS)值及各项Zernike系数,根据PD、屈光度、年龄及性别进行分组比较研究。结果在暗适应瞳孔自然散大状况下,总高阶像差的RMS值为(0.234±0.093)μm,范围为0.05~0.63μm,从3阶至6阶呈递减趋势,各项像差中以3阶慧差、3阶散光及4阶球差的RMS值最显著。高阶像差随着瞳孔和屈光度的增大而相应增大,总高阶像差的RMS值(RMSh)与PD及等效球镜(sphericalequivalent,SE)关系的回归方程为RMSh=-0.250 0.098PD 0.007SE。结论暗适应下,高阶像差具有较大的个体差异,其RMS值从3阶至6阶呈递减趋势,其中以3阶慧差、3阶散光及4阶球差的RMS值最显著。高阶像差随着瞳孔及屈光度的增加而相应增大,且瞳孔大小较屈光度的影响更大。3阶慧差及3阶散光随着年龄的增加而增加。     

Optical response to LASIK surgery for myopia from total and corneal aberration measurements.

PURPOSE: To evaluate the optical aberrations induced by LASIK refractive surgery for myopia on the anterior surface of the cornea and the entire optical system of the eye. METHODS: Total and corneal aberrations were measured in a group of 14 eyes (preoperative myopia ranging from -2.5 to -13 D) before and after LASIK surgery. Total aberrations were measured using a laser ray-tracing technique. Corneal aberrations were obtained from corneal elevation maps measured using a corneal system and custom software. Corneal and total wave aberrations were described as Zernike polynomial expansions. Root-mean-square (RMS) wavefront error was used as a global optical quality metric. RESULTS: Total and corneal aberrations (third-order and higher) showed a statistically significant increase after LASIK myopia surgery, by a factor of 1.92 (total) and 3.72 (corneal), on average. This increase was more pronounced in patients with the highest preoperative myopia. There is a good correlation (r = 0.97, P < 0.0001) between the aberrations induced in the entire optical system and those induced in the anterior corneal surface. However, the anterior corneal spherical aberration increased more than the total spherical aberration, suggesting also a change in the spherical aberration of the posterior corneal surface. Pupil centration and internal optical aberrations, which are not accounted for in corneal topography, play an important role in evaluating individual surgical outcomes. CONCLUSIONS: Because LASIK surgery induces changes in the anterior corneal surface, most changes in the total aberration pattern can be attributed to changes in the anterior corneal aberrations. However, because of individual interactions of the aberrations in the ocular components, a combination of corneal and total aberration measurements is critical to understanding individual outcomes, and by extension, to designing custom ablation algorithms. This comparison also reveals changes in the internal aberrations, consistent with the posterior corneal changes reported using scanning slit corneal topography.     

Pentacam与iTrace像差仪在白内障患者角膜像差测量中的应用

目的探讨利用Pentacam系统测量超声乳化白内障摘出联合人工晶状体（IOL）植入术手术前后角膜前表面高阶像差的变化,比较Pentacam系统与iTrace像差仪测量的术后角膜前表面像差的差异。方法研究为诊断性试验研究。对年龄相关性白内障患者60例79眼行小切口超声乳化白内障摘出联合折叠型IOL植入术,应用Pentacam系统分别于术前和术后2个月测量角膜前表面的像差,观察手术前后角膜前表面像差的变化。术后2个月对所有患者行iTrace像差仪检查,记录总高阶像差、彗差、三叶草像差及球差的均方根（RMS）值。所有手术和检查均由同一位医师操作。所有患者均签署书面知情同意书。结果 Pentacam测量方法检查结果显示,角膜前表面的总高阶像差术前较术后轻度增加,但手术前后变化差异无统计学意义（t=0.717,P〉0.05）;其余各项球差、彗差、三叶草像差以及3～6阶像差手术前后的变化与总高阶像差的检测结果相似,差异均无统计学意义（P〉0.05）。Pentacam和iTrace测量术后角膜前表面的像差发现,Pentacam测量的球差、三叶草像差测量结果较iTrace轻度增加,但差异无统计学意义（P〉0.05）;而Pentacam和iTrace所测量的总高阶像差、球差、3～6阶像差的比较差异均有统计学意义（P〈0.05）。结论小切口超声乳化白内障摘出联合IOL植入术后角膜前表面高阶像差的变化不影响患者的视觉质量,Pentacam和iTrace测量的角膜波前像差结果存在部分差异。     

VisuMax飞秒激光准分子激光原位角膜磨镶术娇正高度近视术后角膜前后表面高阶像差变化

目的 探讨VisuMax飞秒激光准分子激光原位角膜磨镶术(LASIK)矫正高度近视术后角膜前后表面高阶像差的变化情况.方法 前瞻性连续病例研究.选择行LASIK矫正高度近视(等效球镜度数-6.38～-13.50 D)患者22例((41眼),其中使用Visumax飞秒激光制瓣11例(21眼),Moria M3旋转式微型角膜刀制瓣11例(20眼).采用Pentacam-HR眼前节分析系统,分别在术前、术后6个月对术眼进行眼前节三维图像采集,记录基于角膜前后表面高度图获取的分析直径为6 mm的角膜前后表面高阶像差均方根值及各阶像差的Zernike系数,计算彗差和初级球差,采用方差分析及t检验进行统计分析.结果 术后飞秒激光组和角膜刀组的角膜前表面总高阶像差均方根值、彗差、初级球差均较术前显著增加(P<0.05),其中角膜刀组的彗差增加量显著高于飞秒激光组[分别为(0.788±0.592)μm及(0.403±0.572)μm,P<0.05];术后飞秒激光组的角膜后表面总高阶像差均方根值、彗差、初级球差的绝对值均较术前增加(P<0.05),而角膜刀组的角膜后表面像差在手术前后差异无统计学意义(P>0.05);与角膜刀组相比,飞秒激光组术后角膜后表面的彗差增加量更显著[分别为(0.004±0.031)μm及(0.027土0.036)μm,P<0.05].结论 VisuMax飞秒激光LASIK矫正高度近视比角膜刀制瓣引起的角膜前表面彗差增加量较少;其角膜后表面像差亦存在轻微增加,且角膜后表面彗差增加较角膜刀显著,发生机制有待进一步探讨.     

Corneal biomechanical data and biometric parameters measured with Scheimpflug -based devices on normal corneas

AIM: To analyze the correlations between ocular biomechanical and biometric data of the eye, measured by Scheimpflug-based devices on healthy subjects. METHODS: Three consecutive measurements were carried out using the corneal visualization Scheimpflug technology (CorVis ST) device on healthy eyes and the 10 device-specific parameters were recorded. Pentacam HR-derived parameters (corneal curvature radii on the anterior and posterior surfaces; apical pachymetry; corneal volume; corneal aberration data; depth, volume and angle of the anterior chamber) and axial length (AL) from IOLMaster were correlated with the 10 specific CorVis ST parameters. RESULTS: Measurements were conducted in 43 eyes of 43 volunteers (age 61.24±15.72y). The 10 specific CorVis ST data showed significant relationships with corneal curvature radii both on the anterior and posterior surface, pachymetric data, root mean square (RMS) data of lower-order aberrations, and posterior RMS of higher-order aberrations and spherical aberration of the posterior cornea. Anterior chamber depth showed a significant relationship, but there were no significant correlations between corneal volume, anterior chamber volume, mean chamber angle or AL and the 10 specific CorVis ST parameters.     

Q值优化非球面切削矫正高度近视的远期高阶像差观察

目的观察Q值优化的非球面切削准分子激光手术矫正高度近视的远期Q值和高阶像差变化。方法回顾性分析2007年在上海交通大学附属第六人民医院眼科行Q值引导的个体化切削（F—CAT）准分子激光手术的高度近视患者35例（70眼）,其中行准分子激光原位角膜磨镶术（LASIK117例（34眼）,准分子激光上皮瓣下角膜磨镶术（LASEK）18例（36眼）,观察并用配对≠检验比较两种手术方式术前、术后远期角膜Q值和高阶像差的变化,采用独立样本t检验比较两组间各项指标的差异,采用Pearson相关和线性回归分析术后高阶像差的相关影响因素。结果术后3年,所有患者裸眼视力〉10．8,LASIK组和LASEK组安全性指数均〉1,有效性指数均接近1。两组Q值与术前相比,均从负值变为正值。术后总高阶像差均比术前增加,差异有统计学意义（t=-3．90、-6．75,P〈0．01）。术后LASIK组和LASEK组三阶像差均方根（RMS）值（t=-3．50、-5．22）、四阶像差RMS值（t=-6．79、-10．14）、垂直彗差RMS值（t=5．73、-5．50）、球差RMS值（t=-8．57、-13．79）均比术前增加（P〈0．01）,两组间垂直彗差,球差差异均无统计学意义;水平彗差与术前相比差异无统计学意义。术后总高阶像差RMS值（R^2=372,F=16．96,P〈0．01）和术后球差RMS值（R^2=0．224,F=10．93,P〈0．01）与术前等效球镜度、手术光学区大小相关。术后垂直彗差与术前等效球镜度、手术目标Q值相关（R^2=0．224,F=10．93,P〈0．01）。结论Q值引导LASIK和LASEK矫正高度近视手术远期安全、有效。IASIK和LASEK术后Q值均由负值变为正值,远期高阶像差和球差增加。垂直彗差的增加可能与手术瓣蒂位置有关。术后高阶像差与患者术前屈光度、手术方式及光学区相关。     

LASIK术后特殊设计硬性透气性角膜接触镜再矫正前后的视觉质量探讨

目的观察逆几何形特殊设计的硬性透气性角膜接触镜（RGDRGPCL）改善准分子激光原位角膜磨镶术（LASIK）后视觉质量下降的临床效果并探讨其机制。方法前瞻性病例对照研究。2010年1月至2010年10月期间因LASIK术后视觉质量下降要求验配RGDRGPCL的患者20例（28眼）．采用Pentacam三维眼前节分析仪、CGT-1000对比敏感度测量仪测量角膜波前像差、对比敏感度．询问并记录主观症状。并选择同期普通近视患者15例（30眼）,比较两组对象的角膜波前像差。对相关数据进行独立样本t检验、配对样本t检验及直线相关性分析。结果LASIK术后患者总像差、总高阶像差、球差、角膜后表面球差的均方根（RMS）值与普通近视患者比较,差异有统计学意义（t=-7．684、-5．658、-5．342、4．039,P〈0．05）：与自身配戴RGDRGPCL状态下比较,差异也有统计学意义（t=4．510、4．520、3．826、-4．672,P〈0．05）;彗差（水平、垂直）差异无统计学意义。LASIK术后角膜前表面球差值与配戴RGDRGPCL状态下比较,差异有统计学意义（t=4．361,P〈0．01）;配戴RGDRGPCL时的角膜前表面像差与普通近视比较,差异无统计学意义;普通近视患者的总三叶草与LASIK术后（t=-7．464．P〈0．01）及戴镜状态下比较差异有统计学意义（￡=-7．027,P〈0．01）;LASIK术后与配戴RGDRGPCL时的总三叶草比较,差异无统计学意义。患者配戴框架眼镜矫正与配戴RGDRGPCL比较,两者的对比敏感度、眩光对比敏感度差异无统计学意义。LASIK术后配戴RGDRGPCL时的矫正视力与角膜总像差RMS值成负相关关系（r=-0．469,P=0．037）,患者戴镜时主观视觉症状改善满意度为95％。结论角膜高阶像差的增加是引起LASIK术后患者视觉质量下降的主要原因之-,术后患者配戴RGDRGPCL时角膜总像差、球差均方根值等明显降低,有利于改善术后患者视觉质量。     

低中度近视患者眼压、角膜中央厚度与角膜球差及非球面性的关系

ObjectiveTo investigate the correlation between intraocular pressure （IOP） and central corneal thickness （CCT） and corneal spherical aberration as well as asphericity. MethodsThis was a cross-sectional study. Two hundred and sixteen eyes in 108 mild-to-moderate myopia patients were examined with the Pentacam HR anterior segment tomographer. The aspheric coefficient （Q value） and corneal spherical aberration results from the different quadrants in both the anterior and posterior corneas （including superior， inferior， nasal， temporal， horizontal and vertical directions） and the data 6， 7， 8 and 9 mm eccentric diameters were obtained. IOP and CCT were measured by a non-contact tonometer and A-scan ultrasonic corneal pachymeter， respectively. Patients were divided into 2 groups based on the degree of myopia. The relationship between the IOP with and without CCT and corneal spherical aberration as well as asphericity were analyzed. Data was processed using a Pearson correlation analysis， independent samples t test and one-way ANOVA. ResultsIOP was significantly correlated with anterior corneal asphericity （r=-0.30， P<0.05 for right eyes； r=-0.34， P<0.05 for left eyes）， but was not significantly correlated with anterior corneal spherical aberration in the mild myopia group. In the moderate myopia group， although IOP was significantly correlated with anterior corneal spherical aberration （r=0.31， P<0.05 for right eye； r=0.37， P<0.01 for left eye）， there was no significant correlation with anterior corneal Q value. CCT was only significantly correlated with the temporal corneal Q value （r=0.47， P<0.01 for right eyes； r=0.29， P<0.05 for left eyes）. ConclusionIOP induced a decrease in anterior corneal asphericity in mild myopes， however， it was positively correlated with anterior corneal spherical aberration. The reason for the difference may be related to the compensation mechanism of the cornea itself.     

正常人眼角膜前表面光学质量MTF影响因素的探讨

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 sirius 3D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。     

Age-related changes in corneal and ocular higher-order wavefront aberrations

PURPOSE: To investigate age-related changes in ocular and corneal higher-order wavefront aberrations and elucidate relative contributions of the cornea and the lens in the age-related changes. DESIGN: Observational case series. METHODS: Corneal and ocular higher-order wavefront aberrations in the central 6 mm diameter were measured with videokeratography and the Hartmann-Shack wavefront aberrometer in 75 normal eyes of 75 patients with a mean age of 43.5 +/- 11.7 years (range, 18-69 years). Higher-order wavefront aberrations were calculated with Zernike polynomials up to sixth order. From the Zernike coefficients, we calculated root mean square (RMS) of coma and spherical aberration. To examine age-related changes of the polarity of spherical aberration, the changes of the Zernike coefficient Z(4)(0) was also investigated. RESULTS: Both corneal (r =.307, P =.007) and ocular (r =.334, P =.0033) coma RMS showed positive correlations with age. There was a positive correlation between corneal and ocular coma RMS (r =.468, P <.0001). The RMS of corneal spherical aberration did not change with aging (r =.153, P =.1895), whereas the RMS of ocular spherical aberration had a positive correlation with aging (r =.308, P =.0068). CONCLUSIONS: These results suggest that the ocular coma increases with age, mainly because of the increase in the corneal coma, and the ocular spherical aberration increases with age, mainly because of the increase in the spherical aberration in the internal optics.     

New diagnostic methods for imaging the anterior segment of the eye to enable treatment modalities selection

New diagnostic instruments for imaging the anterior segment of the eye have been developed using the corneal topographer, wavefront sensor, and anterior segment optical coherence tomography (OCT). Data obtained from these instruments can be used to choose treatment modalities by providing information that is complementary to slit-lamp examination and visual acuity measurements. Zernike vector analysis was used to evaluate the corneal higher-order aberrations to quantify the effects of the corneal shape on the optical quality of the eye. The analyses showed the optical characteristics of the anterior and posterior surfaces of the cornea in patients with keratoconus or pellucid marginal corneal degeneration. The association between the deterioration of optical quality during rigid gas-permeable contact lens wear in patients with keratoconus and the residual coma due to posterior corneal shape was suggested by the findings made with this method. Zernike vector analyses also revealed the differences in the ocular higher-order aberrations between conventional Laser in situ keratomileusis (LASIK) and custom LASIK. Serial measurements of the ocular higher-order aberrations by a wavefront sensor enabled us to evaluate the effects of tear fluid dynamics on the optical quality of the eye. The findings clarified the characteristics of serial alterations of higher-order aberrations in normal eyes, dry eye with tear deficiency and dry eye with tear evaporation. The effects of internal lubricating agents on the soft contact lenses were also evaluated objectively. In addition, these results suggest that the effects of serial fluctuations in the ocular higher-order aberrations on refractive surgery should be considered. To observe the cornea at the cellular level with anterior segment OCT, a prototype machine of full-field OCT was developed. This made it possible to show epithelial edema in human donor corneas as well as the alterations in the epithelial layer and stromal layer associated with intraocular pressure elevation in ex vivo porcine eyes. An OCT-based corneal topographer was developed using a three-dimensional anterior segment OCT with the swept-source principle. Corneal topographic analyses of the anterior and posterior surfaces either in eyes with keratoconus or following keratoplasty was possible even in where it was difficult for conventional corneal topographers to analyze accurately. Also, OCT-based corneal topographer analyzed the host and donor cornea separately following Descemet stripping automated endothelial keratoplasty by recognizing the host-graft interface. The results from these new diagnostic methods for imaging the anterior segment of eye will be useful for the diagnosis of corneal disorders and the planning of treatment by evaluating the effects of corneal topographic abnormalities and tear fluid dynamics on visual function, by observing the abnormalities of the corneal tissue at the cellular level, and by showing corneal topography in diseased corneas more accurately and non-invasively.