LASIK术后角膜生物力学变化与眼压测量值的相关性

目的 观察LASIK术后角膜生物力学参数和眼压测量值的变化及角膜生物力学变化与眼压的相关性。设计 前瞻性病例系列。研究对象 哈尔滨医科大学附属第一医院2014年1-12月LASIK手术患者81例（162眼）。方法 应用非接触眼压计（non-contact tonometer,NCT）分别在术前及术后3个月测量眼压。同时应用眼反应分析仪（ocular response analyzer,ORA）测量角膜滞后量（corneal hysteresis,CH）、角膜阻力因子（corneal resistance factor, CRF）、模拟Goldmann 眼压（Goldmann intraocular pressure,IOPg）和角膜补偿眼压（corneal-compensated intraocular pressure,IOPcc）。比较手术前后各参数的变化并分析术后角膜生物力学参数变化与眼压测量值的相关性。 主要指标 手术前后NCT、IOPcc、IOPg、CH、CRF。 结果 LASIK术后3个月CH、CRF、IOPcc、IOPg、NCT测量值与术前比较均显著降低,术后IOPcc与IOPg和NCT之间比较差异均有统计学意义（P<0.05）;△CH、△CRF与△IOPcc、△IOPcc- IOPg和△IOPcc-△NCT均成负相关,△CH、△CRF与△IOPg和△NCT均成正相关（P<0.05）;CH和CRF的减少量与眼压测量值下降具有相关性（P<0.05）。结论 LASIK术后角膜生物力学参数和眼压测量值均较术前显著降低,眼压测量值下降与CH和CRF的减少量具有相关性,说明眼压下降的程度可能受角膜生物力学特性的影响。     

手法小切口白内障摘除术后早期角膜生物力学特性的变化

目的:观察年龄相关性白内障患者手法小切口白内障摘除术(manual small incision cataract surgery,MSICS)后1d角膜滞后性(corneal hysteretic,CH)、角膜阻力因数(cornealresistance factor,CRF)、角膜补偿眼压(corneal compensa-ted IOP,IOPcc)、Goldmann相关眼压(goldmann correlatedIOP,IOPg)的变化规律,并探讨MSICS术后早期角膜生物力学特性改变的相关因素。方法:应用Reichert眼反应分析仪(ocular response analy-zer,ORA)测量50例50眼年龄相关性白内障患者术眼MSICS术前及术后1d的CH,CRF,IOPg,IOPcc。用SPSS10.0统计学软件分析各测量值的变化规律以及CH变化量与眼压变化量的相关性。结果:术后1d的CH,CRF较术前下降(P<0.01;P<0.01),IOPcc,IOPg较术前升高(P<0.01;P=0.001),CH降低量与眼压增加量呈正相关性(IOPg,r=0.492,P<0.01;IOPcc,r=0.688,P<0.01)。结论:年龄相关性白内障患者手法小切口白内障摘除术后早期角膜生物力学特性明显改变,术后角膜不同程度的水肿和眼压的升高可能是导致改变的主要原因。     

眼反应分析仪与非接触眼压计眼压测量的对比观察

目的比较眼反应分析仪(ORA)与非接触眼压计(NCT)测量眼压结果的差异,分析ORA、NCT测量结果与角膜中央厚度(CCT)的关系。方法近视患者57例(114只眼),于准分子激光手术前行ORA测量,得出角膜补偿眼压(IOPcc)和Goldmann相关眼压值(IOPg)两个数值,NCT测眼压3次取平均值。结果 ORA测得IOPcc平均值16.85 mm Hg,IOPpg平均值15.26 mm Hg,NCT眼压计测得平均值15.66 mm Hg;IOPcc>NCT>IOPg。IOPcc、IOPg与NCT所测眼压值比较,差异均有统计学意义(P<0.05)。NCT和IOPg均与CCT呈正相关(r:分别为0.463和0.419,P<0.05);IOPcc与CCT无相关性(r:0.230,P>0.05)。结论 ORA测量屈光不正患者的眼压与NCT测量结果存在一定差异,其中IOPcc不受角膜厚度的影响,在临床运用中准确性较好。     

角膜补偿眼压与前房穿刺测量眼内压的比较

目的 比较角膜补偿眼压(IOPcc)与前房穿刺测量眼压(direct intracameral IOP,IOPintra),探讨角膜生物特性对眼压测量的影响.方法 双肓前瞻性研究.拟行超声乳化手术患者73例(73只眼),随机选择1只眼.超声测厚仪测量中央角膜厚度(CCT),ORA测量IOPcc和角膜生物属性:角膜滞后性(cornealhysteresis,CH).角膜阻力因子(corneal resistance factor,CRF).应用IOD眼压测量装置行前房穿刺测量IOPintra.结果 IOPintra为(15.48±4.64)mmHg,IOPcc为(16.63±3.68)mmHg;IOPcc高出IOPintra(1.15±4.12)mmHg(P=0.019);IOPcc和IOPintra与CH、CRF相关,IOPcc,IOPintra及两者的差异与CCT不相关;IOPcc与IOPintra的差异与cH相关(r=-0.283 P=0.015).结论 IOPcc读数比IOPintra高1.15mmHg,其差异受CH影响.角膜生物属性对眼压测量的影响需慎重考虑.     

角膜补偿眼压（IOPcc）和5种眼压校正公式所得校正眼压的一致性及IOPcc、模拟Goldmann眼压与眼球各参数的相关性分析

目的　比较眼反应分析仪测得的角膜补偿眼压（corneal-compensated intraocular pressure,IOPcc）和Sirius眼前节分析系统内置的5种眼压校正公式所得校正眼压的一致性,分析IOPcc、模拟Goldmann眼压（Goldmann-correlated intraocular pressure,IOPg）与眼球各参数的相关性。方法　选取2016年11月至2017年3月在我院眼科中心行近视激光治疗的患者90例90眼,年龄18～37（24.47±5.57）岁。应用Sirius眼前节分析系统对所有患者按常规方法测量3次,选择最佳测量结果作为各参数最终结果。应用眼反应分析仪测量患者的角膜生物力学参数。根据眼反应分析仪测量的IOPg输入Sirius眼前节分析系统内置的5种眼压校正公式进行计算,得到的校正眼压分别记录为Dresdner校正眼压、Ehlers校正眼压、Kohlhaas校正眼压、Orssengo/Pye校正眼压和Shah校正眼压。将所得的5种校正眼压和非接触性眼压计眼压与眼反应分析仪测得的IOPcc进行一致性分析。对IOPcc、IOPg与角膜滞后量、角膜阻力因子、眼球各参数进行相关分析。结果　Kohlhaas校正眼压和IOPcc比较差异有统计学意义（P<0.05）。Dresdner校正眼压、Orssengo/Pye校正眼压与IOPcc的一致性较好,95%一致性界限分别为 （-2.09～2.55）mmHg、（-2.38～2.37）mmHg;其中Dresdner校正眼压与IOPcc的95%一致性界限宽度最窄。IOPcc与角膜滞后量、角膜阻力因子以及眼球各参数均无相关性,而IOPg与角膜阻力因子、中央角膜厚度、角膜体积呈正相关关系 （均为P<0.05）。结论　Dresdner校正眼压、Orssengo/Pye校正眼压与IOPcc的一致性较好;眼球大部分参数对IOPcc影响小。     

单纯近视患者Corvis ST测定的角膜形变参数与角膜形态学参数的相关性

背景 Corvis ST生物力学眼压测量仪(Corvis ST)可测得角膜形变的参数,同时可记录角膜受力时的动态变化过程,对近视眼行角膜屈光手术前后角膜结构和功能的预测具有重要的临床意义,但单纯近视眼角膜各形变参数的测定值范围及意义有待研究. 目的 利用Corvis ST测量近视眼角膜形变参数值范围并分析其临床意义,为角膜屈光手术的术前筛查及术后稳定性、安全性的预测等提供参考.方法 采用描述性研究方法,纳入2014年6月至2015年1月在天津市眼科医院拟行角膜屈光手术的单纯近视眼患者257例477眼,所有受检眼均采用Corvis ST测定角膜形变参数,包括第1次压平时间(1stA-time)、角膜长度(1stA-length)和压平速度(1stA-velocity),第2次压平时间(2ndA-time)、角膜长度(2ndA-length)和压平速度(2ndA-velocity),产生最大压陷的时间(HC-time)和最大压陷时的变形幅度(HC-DA)、峰距(HC-PD)、反向曲率半径(HC-R),非接触式眼压(IOPnct)和中央角膜厚度(CCTst);用Pentacam三维眼前节分析诊断系统(Pentacam)检查受检眼结构参数CCT和角膜曲率;用眼反应分析仪(ORA)测定受检眼角膜生物力学参数,包括角膜阻力因子(CRF)、角膜滞后量(CH)、模拟Goldmann眼压(IOPg)和角膜补偿眼压(IOPcc).对上述参数值行Shapiro-Wilk正态性检验并计算各参数总体均值的95％可信区间(CI);用Pearson线性相关分析或Spearman秩相关分析法对角膜形变参数与角膜结构参数及角膜生物力学参数的相关性进行分析;采用多元线性回归法分析1stA-time、2nd A-time和HC-DA随着各角膜形态学及角膜生物力学参数的变化. 结果 角膜形变参数中仅1stA-time、2nd A-time、HC-time、HC-DA、CCTst和IOPnct服从正态分布;1stA-time、1stA-length、2ndA-length、2ndA-velocity、HC-R与CCT值间均呈正相关(r=0.338、rs=0.129、rs=0.282、rs=0.374、r=0.306,均P＜0.01),而1stA-velocity、2ndA-time、HC-DA及HC-PD与CCT均呈负相关(rs=-0.235、r=-0.130、r=-0.259、r=-0.226,均P＜0.01).CRF和CH与1stA-time、2ndA-length、2ndA-velocity、HC-time、HC-R均呈正相关(均P＜0.05),而与HC-PD、△A-length均呈负相关(均P＜0.05).1stA-time、2nd A-time和HC-DA均随着CRF和IOPcc改变发生变化,回归方程分别为1stA-time=6.185+0.066CRF+0.034IOPcc(F=300.123,P=0.000)、2ndA-time=23.397-0.074I0Pcc-0.044CRF(F=227.979,P=0.000)和HC-DA=1.523-0.017IOPcc-0.017CRF(F=152.662,P=0.000).Corvis ST测得的CCTst值、IOPst值和IOPnct值均明显低于Pentacam测得的CCT[(548.23±26.31) μm]和ORA测得的IOPg值[(15.02±2.72) mmHg](1 mmHg =0.133 kPa)和IOPcc值[(16.02±2.56) mmHg],差异均有统计学意义(t=11.00、2.919、6.815,均P＜0.01).结论 Corvis ST测定的单纯近视眼的角膜形变参数可客观定量描述角膜生物力学特性,IOP及角膜3 mm区陡中心曲率(K2)均可影响角膜的形变反应,Corvis ST在测量CCT及IOP方面的可信度有待进一步研究.     

角膜生物参数对青光眼患者眼压测量影响的研究

目的:探讨角膜生物参数对青光眼患者眼压测量的影响。方法:对80例121眼青光眼患者进行眼反应分析仪(ocular response analyzer,ORA)与Goldmann压平眼压计(Goldmann applanation tonometer,GAT)测量,并用先进的OrbscanⅡ眼前节分析系统测量中央角膜厚度(central corneal thickness,CCT)。结果:平均矫正眼压(IOPcc)值17.41±5.62mmHg;平均GAT值15.76±6.06mmHg;IOPcc与角膜滞后性(cornealhysteresis,CH)有相关性(P=0.000;r=-0.236);IOPcc与GAT显著相关(P=0.000;r=0.857);IOPcc与CCT无相关性。结论:对已经诊断的青光眼患者,平均IOPcc值高于平均GAT值;随着CH的降低,IOPcc值有升高的趋势;且IOPcc值不受CCT值的影响。     

飞秒激光LASIK术后角膜生物力学各指标和眼压的改变

目的 探讨准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)使用飞秒激光制瓣对近视患者角膜生物力学各指标和眼压的影响.方法 选取111例(222眼)近视患者均行飞秒激光LASIK.分别于术前、术后3个月应用眼反应分析仪检测角膜补偿眼压(corneal compensated intraocular pressure,IOPcc)、模拟Goldmann眼压(Goldmann correlated IOP value,IOPg)、角膜阻力因子(corneal resistance factor,CRF)、角膜滞后量(corneal hysteresis,CH),A型超声测量角膜厚度.比较术后3个月与术前各测量值的差异.结果 术后3个月角膜厚度为(444.00±35.31) μm与术前(536.86±27.09) μm比较,差异有显著统计学意义(t=-55.08,P=0.000),切削深度(92.85±25.12) μm.术后3个月IOPcc、IOPg分别为(14.05±2.32) mmHg(1kPa=7.5 mmHg)、(10.00±2.55) mmHg,较术前(16.03±3.33) mmHg、(14.96±3.32) mmHg显著降低(t分别为-11.111、-24.792,P分别为0.000、0.000).IOPcc、IOPg分别较术前降低(1.98±2.66) mmHg、(4.95±2.98) mmHg. CRF、CH术后测量值(6.54±1.39) mmHg、(7.77±1.23) mmHg较术前(9.90±1.83) mmHg、(9.92±1.62) mmHg显著降低(t分别为-27.976、-21.773,P分别为0.000、0.000).CRF、CH分别较术前降低(3.36±1.79) mmHg、(2.15±1.47) mmHg.角膜切削厚度与CRF、CH改变量呈正相关(r=0.246、0.166,P =0.000、0.013).结论 飞秒激光LASIK术后角膜生物力学各指标和眼压均较术前显著降低,角膜生物力学改变与切削量有关.     

近视LASIK术后角膜生物力学参数变化的相关性

目的:观察近视LASIK术后角膜生物力学参数与形态参数变化的相关性。方法:近视患者69例136眼,于LASIK术前及术后1mo行眼反应分析仪(ORA)测量角膜滞后(CH)和角膜阻力因子(CRF),Pentacam眼前节分析仪测量眼前节参数。计算术后角膜生物力学参数变化ΔCH及ΔCRF,Pentacam测量角膜中央厚度变化ΔCCT,中央2,4,6mm平均角膜厚度变化(ΔCCT2mm,ΔCCT4mm和ΔCCT6mm),角膜容积变化ΔCV,角膜前后表面曲率半径变化ΔRa和ΔRp,分析ΔCH和ΔCRF与角膜形态参数的相关性。结果:LASIK术前平均CH及CRF(9.99±1.38和9.96±1.30mmHg)明显高于术后1moCH和CRF(7.90±1.16和6.49±1.28mmHg),差异具有统计学意义(P<0.05)。LASIK术后ΔCH和ΔCRF与ΔRp和ΔCCT6mm无相关性,ΔCH和ΔCRF与ΔCCT,ΔCCT2mm,ΔCCT4mm和ΔCV呈正相关(r:0.513,0.397,0.329和0.314,P<0.05;r:0.616,0.504,0.484和0.466,P<0.01);ΔCRF与ΔRa呈负相关(r:-0.374,P<0.01)。结论:近视LASIK术后角膜CH和CRF变化与角膜厚度及容积有关,CRF评价LASIK术后角膜生物力学变化比CH更有价值。     

高度近视眼准分子激光角膜前弹力层下磨镶术前后角膜生物力学变化的研究

目的分析和探讨高度近视患者行准分子激光角膜前弹力层下磨镶术（SBK）前后角膜生物力学特性变化的特点。方法前瞻性系列病例研究。高度近视患者36例（65眼）,年龄19～34岁,平均（22．9±3．6）岁,等效球镜度-6．375—12．50D,平均（-8．35±1．21）D,所有患者均行SBK。术前和术后1个月,应用眼反应分析仪（ORA）对患者的模拟Goldmann眼压（IOPg）、角膜补偿眼压（IOPcc）、角膜阻力因子（CRF）、角膜滞后量（CH）及内向压平时间（Timeln）和外向压平时间（TimeOut）进行测量和分析。应用配对t检验对手术前后IOPg、IOPcc、CRF、CH、Timeln、TimeOut和TimeOut—Timeln变化进行对比分析,采用多重回归和Pearson相关分析影响角膜生物力学特性变化的因素。结果术前IOPg、IOPcc、CRF、CH和TimeIn、TimeOut及TimeOut．Timeln分别为（17．5±3．0）mmHg、（17．6±2．9）mmHg、（11．1±1．4）mmHg、（10．5±1．3）mmHg、（8．0±0．4）ms、（18．6±0．2）ms和（10．7±0．4）ms,术后1个月分别为（12．4±3．5）mmHg、（16．4±3．3）mmHg、（7．0±1．2）mmHg、（7．5±1．0）mmHg、（7．2±O．5）ms、（18．4±0．2）ms和（11．2±0．5）ms。手术前后比较,差异均有显著统计学意义（t=14．2、3．5、28．1、24．9、17．4、16．2、-10．7,P均〈0．01）。aIOPg、aCRF与切削量（AD）呈正相关（r=0．247,P=0．047;r=0．298,P=0．016）,而aIOPcc、aCH和／XTimeln、ATimeOut及a（TimeOut-Timeln）与AD的相关性无统计学意义。结论SBK矫正高度近视会对角膜生物力学产生一定的影响,使其术后角膜生物力学信号发生一系列变化,与激光切削量有一定的相关性。     

同轴微切口超声乳化白内障吸出术后角膜生物力学变化

目的　比较同轴微切口超声乳化白内障吸出术（ｐｈａｃｏｅｍｕｌｓｉｆｉｃａｔｉｏｎ,Ｐｈａｃｏ）及标准切口Ｐｈａｃｏ术后角膜生物力学的变化。方法　年龄相关性白内障患者３１２例（３１２眼）随机分成两组。其中研究组（２．２ｍｍ同轴微切口组）１５９例,对照组（３．０ｍｍ标准切口组）１５３例。记录两组术前数据,包括年龄、性别、裸眼视力（ｕｎｃｏｒｒｅｃｔｅｄｖｉｓｕａｌａｃｕｉｔｙ,ＵＣ-ＶＡ）、最佳矫正视力（ｂｅｓｔｃｏｒｒｅｃｔｅｄｖｉｓｕａｌａｃｕｉｔｙ,ＢＣＶＡ）、角膜滞后性（ｃｏｒｎｅａｌｈｙｓｔｅｒｅｔｉｅ,ＣＨ）、角膜阻力因数（ｃｏｒｎｅａｌｒｅｓｉｓｔａｎｃｅｆａｃｔｏｒ,ＣＲＦ）、Ｇｏｌｄｍａｎｎ相关眼压（ｇｏｌｄｍａｎｎｃｏｒｒｅｌａｔｅｄｉｎｔｒａｏｃｕｌａｒｐｒｅｓｓｕｒｅ,ＩＯＰｇ）、角膜补偿眼压（ｃｏｒｎｅａｌｃｏｍｐｅｎｓａｔｅｄＩＯＰ,ＩＯＰｃｃ）、中央角膜厚度（ｃｅｎｔｒａｌｃｏｒｎｅａｌｔｈｉｃｋｎｅｓｓ,ＣＣＴ）、角膜内皮细胞计数（ｅｎｄｏｔｈｅｌｉａｌｃｅｌｌｃｏｕｎｔ,ＥＣＣ）;术中数据包括累积能量复合参数（ｃｕｍｕｌａｔｉｖｅｄｉｓｓｉｐａｔｅｄｅｎｅｒｇｙ,ＣＤＥ）、手术时间。术后１ｄ、１周、２周、１个月复查,比较两组ＵＣＶＡ、ＢＣＶＡ、ＥＣＣ、ＣＣＴ、ＣＨ、ＩＯＰｇ、ＣＲＦ和ＩＯＰｃｃ。结果　术后１ｄ两组ＣＨ、ＣＲＦ均较术前明显降低,差异均有统计学意义（均为Ｐ＜０．０５）。术后１周,研究组ＣＨ、ＣＲＦ与术前差异均无统计学意义（均为Ｐ＞０．０５）;对照组ＣＨ、ＣＲＦ较术前降低,差异均有统计学意义（均为Ｐ＜０．０５）。术后２周,两组ＣＨ、ＣＲＦ均恢复至术前水平（均为Ｐ＞０．０５）;两组ＩＯＰｇ、ＩＯＰｃｃ仍高于术前（均为Ｐ＜０．０５）,而低于术后１周（均为Ｐ＜０．０５）;两组ＣＣＴ恢复至术前水平（均为Ｐ＞０．０５）。术后４周,两组ＣＨ、ＣＲＦ、ＩＯＰｇ、ＩＯＰｃｃ、ＣＣＴ均恢复至术前水平（均为Ｐ＞０．０５）。术前,两组ＣＨ、ＣＲＦ与ＣＣＴ存在正相关性（研究组:ｒ１＝０．４３,ｒ２＝０．５２,对照组:ｒ１＝０．５６,ｒ２＝０．５３;均为Ｐ＜０．０５）。术后１ｄ,两组ＣＨ与ＣＣＴ均无相关性（ｒ１＝０．１３,ｒ２＝０．１０,均为Ｐ＞０．０５）。两组的ＣＲＦ值与ＣＣＴ在不同时相始终存在相关性（均为Ｐ＜０．０５）。两组间不同时相的ＣＨ与ＣＲＦ均存在正相关性（均为Ｐ＜０．０５）。结论　同轴微切口Ｐｈａｃｏ和标准切口Ｐｈａｃｏ均会改变角膜生物力学特征。同轴微切口Ｐｈａｃｏ比标准切口Ｐｈａｃｏ术后角膜生物力学特征恢复更快。     

Influence of corneal astigmatism, corneal curvature and meridional differences on corneal hysteresis and corneal resistance factor

Background: This study investigated the influence of corneal astigmatism, corneal curvature and meridional differences on corneal hysteresis (CH) and the corneal resistance factor (CRF) in a group of normal Chinese persons. Methods: Ninety‐five participants were recruited and data from the eye with higher corneal astigmatism were analysed. The anterior corneal curvature was measured by corneal topography. The Goldmann‐correlated intraocular pressure (IOPg), corneal‐compensated intraocular pressure (IOPcc), CH and CRF at different meridians (default horizontal position, 10°, 20° and 30° along the superotemporal and inferonasal meridians) were obtained from an ocular response analyser. The corneal powers at these specific meridians also were calculated. Results: At the default position, the IOPg and CRF had weak correlations with corneal astigmatism, while the IOPcc and CH were not significantly correlated with corneal astigmatism. Both the IOPg and IOPcc were measured significantly higher at the default position. The CH and CRF were lower at the default position but the difference in the CRF from obliquity could not reach statistical significance. The CH was not significantly correlated with the corneal power at all meridians. The CRF correlated with the corneal power only at 30° superotemporal. Conclusion: Corneal astigmatism and head tilt did not have much effect on the measurement of CH and the CRF, both of which were lowest along the horizontal meridian. Clinically, the difference was small. The influence of corneal power on CH and the CRF was minimal.     

Corneal Biomechanical Characteristics in Patıents with Behçet Disease

Aim: To examine corneal biomechanical properties, intraocular pressure, and central corneal thickness in uveitic eyes with Behçet disease (BD) and to compare them with healthy controls. Methods: This study included 40 eyes of 34 patients with ocular BD and 20 eyes of 20 healthy controls. Eyes with ocular BD were subdivided into active and inactive groups. Ocular response analyzer (ORA) measurements were performed on the 20 eyes of 16 patients with active BD (group 1), 20 eyes of 18 patients with inactive BD (group 2), and 20 eyes of 20 healthy volunteers who served as the control group (group 3). Corneal hysteresis (CH), corneal resistance factor (CRF), intraocular pressure (Goldmann correlated [IOPg], and corneal compensated [IOPcc]) and central corneal thickness (CCT) values were recorded. Results: Mean age of patients in groups 1, 2, and 3 was 33.81?±?9.36, 32.38?±?9.08, and 31.05?±?5.85 years, respectively (p?=?0.76). Mean CH, CRF, IOPg, IOPcc, and CCT values in groups 1, 2, and 3 were [8.51?±?1.88, 9.72?±?2.11, 19.87?±?2.92, 16.13?±?3.29, and 592.50?±?39.95], [8.46?±?1.82, 8.45?±?1.98, 15.89?±?2.68, 15.35?±?2.91, and 528.35?±?19.18], and [8.47?±?1.48, 8.43?±?1.58, 15.59?±?2.74, 15.42?±?3.19, and 526.30?±?18.21], respectively [(p₁?=?0.040, 0.904, <0.001, 0.495 and <0.001 for CRF, CH, IOPg, IOPcc and CCT in group 1, respectively), (p₂?=?0.989, 0.904, 0.659, 0.989, and 0.989 for CRF, CH, IOPg, IOPcc and CCT in group 2, respectively), (p₃?=?0.989, 0.904, 0.660, 0.989, and 0.989 for CRF, CH, IOPg, IOPcc and CCT in group 3, respectively)]. Conclusion: CRF, IOPg, and CCT values altered in active BD group when compared with inactive BD and control group (p?相似文献   

Are There Any Changes in Corneal Biomechanics and Central Corneal Thickness in Fuchs’ Uveitis?

Purpose: To compare corneal biomechanics, intraocular pressure (IOP) and central corneal thickness (CCT) of 38 patients with unilateral Fuchs’ uveitis (FU) with 42 healthy controls.

Methods: Corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated and corneal-compensated IOP (IOPg and IOPcc, respectively) and CCT were measured.

Results: The mean CH, CRF, and IOPg of the involved FU eyes were significantly lower (9.5?±?1.6, 9.0?±?1.9 and 13.1?±?4.3?mmHg) than contralateral eyes (10.1?±?1.7, 9.9?±?1.7 and 14.6?±?3.4?mmHg), and controls (10.5?±?1.5, 10.3?±?1.5 and 14.8?±?2.5?mmHg), respectively. There was no significant difference for mean IOPcc between involved FU or contralateral eyes and controls (14.8?±?4.1, 15.5?±?3.4 and 15.0?±?2.7?mmHg). The CCT values correlated with CH and CRF in the involved and contralateral eyes.

Conclusions: Involved FU eyes had lower CH, CRF, and IOPg than contralateral eyes and controls, with no difference regarding IOPcc.     

Corneal biomechanical properties in normal‐tension glaucoma

Purpose: To investigate the intraocular pressure (IOP) and corneal biomechanical properties of normal and normal‐tension glaucoma (NTG) eyes. Methods: This study included 83 normal and 83 NTG eyes. We measured corneal‐compensated IOP (IOPcc), Goldmann‐correlated IOP (IOPg), corneal resistance factor (CRF), corneal hysteresis (CH) and central corneal thickness (CCT) three times each for normal and NTG eyes using an Ocular Response Analyzer (ORA). Results: No significant difference in CCT was seen between normal eyes (541.4 ± 26.8 μm) and NTG eyes (535.4 ± 24.9 μm; p = 0.16). IOPcc was significantly higher in NTG eyes (16.1 ± 2.6 mmHg) than in normal eyes (15.1 ± 2.9 mmHg; p = 0.01), while IOPg was significantly lower in NTG eyes (14.1 ± 2.7 mmHg) than in normal eyes (15.1 ± 3.0 mmHg; p = 0.04). CRF and CH were significantly lower in NTG eyes (CRF, 8.9 ± 1.5 mmHg; CH, 9.2 ± 1.3 mmHg) than in normal eyes (CRF, 10.6 ± 1.4 mmHg; CH, 10.8 ± 1.3 mmHg; p < 0.0001 each). Conclusion: IOPcc was significantly higher in NTG eyes than in normal eyes. The ORA may be useful for distinguishing between the IOPcc of NTG eyes with normal IOP and that of normal eyes. In addition, the ORA enables CRF and CH to be measured in vivo, and weakness of the lamina cribrosa may be clinically inferred from the fact that CRF and CH were reduced in NTG eyes in our study. Low CRF and CH may be clues to the pathology of NTG.     

Corneal biomechanical changes and intraocular pressure in patients with thyroid orbitopathy

AIM: To determine the relevance of the objective parameters addressing the altered biomechanical properties of cornea for glaucoma monitoring in patients with mild or moderate thyroid associated orbitopathy (TAO), and in healthy individuals. METHODS: Twenty-five patients with TAO (group 1) and 25 healthy adults (group 2) were included to the study. Both groups were of a similar age and the ratio women:man. For each patient, the following parameters of both eyes were measured with ocular response analyzer (ORA): corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann correlated intraocular pressure (IOPg) and corneal compensated intraocular pressure (IOPcc). In both groups participating in our study, all measurements were performed within minutes to reduce the diurnal effects. RESULTS: The mean age in group 1 was 56±11y and 76% were women, 24% were men. The mean age in group 2 was 64±11y and 68% were women, 32% were men. CH correlated negatively with IOPg in group 1 (r2=0.10, P<0.05). IOPg strongly correlated with IOPcc in both groups (group 1: r2=0.79, P<0.0001; group 2: r2=0.85, P<0.0001). There was positive correlation between CRF and IOPg in group 1 (r2=0.12, P<0.05) and in group 2 (r2=0.31, P<0.0001). Statistical analysis revealed no significant correlation between CRF and IOPcc in group 1 (r2=0.009, P>0.05) and also no significant correlation in group 2 (r2=0.04, P>0.05). CRF mean value in group 2 (11.51±1.72 mm Hg) was higher than in group 1 (10.85±1.45 mm Hg) (P<0.05). IOPg strongly correlated with IOPcc in both groups (group 1: r2=0.79, P<0.0001; group 2: r2=0.85, P<0.0001). There was also strong correlation between CRF and CH in both populations: group 1: (r2=0.58, P<0.0001), group 2: (r2=0.41, P<0.0001). CONCLUSION: Biomechanical parameters of cornea, as quantified by CH and CRF, and measured together with IOPcc, precisely reveal glaucoma staging in TAO and thus are reliable for diagnosing and follow-up in clinical practice.     

Corneal biomechanical properties changes after coaxial 2.2-mm microincision and standard 3.0-mm phacoemulsification

AIM: To compare the changes in corneal biomechanics measured by ocular response analyzer (ORA) after 2.2-mm microincision cataract surgery and 3.0-mm standard coaxial phacoemulsification. METHODS: The prospective nonrandomized study comprised eyes with cataract that had 2.2-mm coaxial microincision or 3.0-mm standard incision phacoemulsification. The corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated intraocular pressure (IOPcc) and Goldmann-correlated intraocular pressure (IOPg) were measured by ORA preoperatively and at 1d, 1-, 2-, 3- and 4-week postoperatively. Results were analyzed and compared between groups. RESULTS: In both groups, CH decreased in the immediate postoperative period (P<0.05), returned to the preoperative level at one week (P=0.249) in the 2.2-mm group, and at two weeks in the 3.0-mm group (P=0.264); there was no significant change in CRF values. In 2.2-mm group, mean IOPcc and IOPg increased at 1d postoperatively (both P<0.05), and returned to preoperative level at one week (P=0.491 and P=0.923, respectively). In 3.0-mm group, mean IOPcc and IOPg increased at 1d and 1wk postoperatively (P=0.005 and P=0.029, respectively), and returned to preoperative level at 2wk (P=0.347 and P=0.887, respectively). CONCLUSION: Significant differences between preoperative and postoperative corneal biomechanical values were found for CH, IOPcc and IOPg. But the recovery time courses were different between the two groups. The 2.2-mm coaxial microincision cataract surgery group seemed recovery faster compared to the 3.0-mm standard coaxial phacoemulsification group.     

Effect of biometric characteristics on biomechanical properties of the cornea in cataract patient

AIM: To determine the impact of biometric characteristics on the biomechanical properties of the human cornea using the ocular response analyzer (ORA) and standard comprehensive ophthalmic examinations before and after standard phacoemulsification. METHODS: This study comprised 54 eyes with cataract with significant lens opacification in stages I or II that underwent phacoemulsification (2.8 mm incision). Corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg), and corneal-compensated intraocular pressure (IOPcc) were measured by ORA preoperatively and at 1mo postoperatively. Biometric characteristics were derived from corneal topography [TMS-5, anterior equivalent (EQTMS) and cylindric (CYLTMS) power], corneal tomography [Casia, anterior and posterior equivalent (EQaCASIC, EQpCASIA) and cylindric (CYLaCASIA, CYLpCASIA) power], keratometry [IOLMaster, anterior equivalent (EQIOL) and cylindric (CYLIOL) power] and autorefractor [anterior equivalent (EQAR)]. Results from ORA were analyzed and correlated with those from all other examinations taken at the same time point. RESULTS: Preoperatively, CH correlated with EQpCASIA and CYLpCASIA only (P=0.001, P=0.002). Postoperatively, IOPg and IOPcc correlated with all equivalent powers (EQTMS, EQIOL, EQAR, EQaCASIA and EQpCASIA) (P=0.001, P=0.007, P=0.001, P=0.015, P=0.03 for IOPg and P<0.001, P=0.003, P<0.001, P=0.009, P=0.014 for IOPcc). CH correlated postoperatively with EQaCASIA and EQpCASIC only (P=0.021, P=0.022). CONCLUSION: Biometric characteristics may significantly affect biomechanical properties of the cornea in terms of CH, IOPcc and IOPg before, but even more after cataract surgery.     

Reproducibility of viscoelastic property and intraocular pressure measurements obtained with the Ocular Response Analyzer

Purpose: To analyse the reproducibility of corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann‐correlated intraocular pressure (IOPg) and corneal‐compensated intraocular pressure (IOPcc) obtained with the ocular response analyzer (ORA). Methods: This is a prospective study, nonmasked, of eight successive examinations with the ORA device in 60 normal eyes. Using 30 eyes (one eye per subject), the reproducibility was assessed by comparing the first series of four examinations to the second four and by calculating the within‐subject coefficient of variation. The correlation and difference with the fellow eye were analysed, respectively. Results: The mean values were 10.7 ± 1.8 mmHg, CRF; 10.6 ± 1.6 mmHg, CH; 15.9 ± 3.9 mmHg, IOPg and 16.2 ± 3.7 mmHg, IOPcc. The reproducibility was significantly different for CRF (5.2 ± 5.9%), CH (7.3 ± 8.6%), IOPg (7.7 ± 6.7%) and IOPcc (10.1 ± 8.0%); p < 0.001. Considering the reproducibility, CRF correlated with CH (rs = 0.55; p < 0.001) and showed to be independent of IOPg and IOPcc. The score spread was best for CRF (2.6 ± 1.5 mmHg; 24.0%) compared to IOPg (4.3 ± 1.5 mmHg; 28.1%) and CH (3.1 ± 1.7 mmHg; 29.9%) and worst for IOPcc (5.5 ± 2.5 mmHg; 34.4%). The lowest difference with the fellow eye was observed for CRF (5.0%; p = 0.09). The correlation with the fellow eye was high, especially for IOPcc and CRF (rs > 0.9; p < 0.001) followed by IOPg and CH (rs > 0.8; p < 0.001). Conclusion: The ORA device provides reproducible information on viscoelastic properties of the cornea in normal eyes notably CRF and CH. IOPcc was less reproducible. Four measurements per eye were necessary to reach a 10% precision and six for 5%.