SMILE与FS-LASIK术后眼压和角膜生物力学指标的变化比较

目的：比较飞秒激光小切口角膜基质透镜取出术(small incision lenticule extraction,SMILE)、飞秒辅助LASIK术(FS-LASIK)两种手术方式术后眼压和角膜生物力学指标的变化。

方法：选取我院自愿接受SMILE手术101例202眼和FS-LASIK手术101例202眼近视患者,分别于术前、术后1mo应用眼反应分析仪(ocular response analyzer,ORA)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)。比较术后1mo与术前测量值的差异,两组CRF、CH降低值的差异。

结果：术后1mo SMILE组IOPcc、IOPg分别为13.84±2.22、10.81±2.52mmHg,较术前16.15±2.90、15.95±3.08mmHg显著降低(t=-13.58、-32.91,均P<0.01)。CRF、CH术后测量值7.52±1.41、8.66±1.19mmHg较术前10.72±1.61、10.60±1.43mmHg显著降低(t=-41.21、-24.03,均P<0.01)。CRF、CH分别较术前降低3.19±1.10、1.93±1.14mmHg。FS-LASIK组术后1mo IOPcc、IOPg分别为13.99±2.33、10.10±2.55mmHg,较术前15.88±3.29、14.86±3.34mmHg显著降低(t=-10.09、-23.00,均P<0.01)。CRF、CH术后测量值6.68±1.14、7.90±1.27mmHg较术前9.93±1.85、9.98±1.60mmHg显著降低(t=-24.84、-18.90,均P<0.01)。CRF、CH分别较术前降低3.25±1.86、2.08±1.57mmHg。CRF、CH术后降低值SMILE 组显著小于FS-LASIK组(t=-0.351、-1.081,均P<0.01)。

结论：两种手术方式术后角膜生物力学和眼压测量值均较术前显著降低。CRF、CH术后降低值,SMILE 组显著低于FS-LASIK组。     

飞秒激光LASIK术后角膜生物力学的改变

目的：探讨飞秒激光LASIK术后角膜生物力学指标的改变,为飞秒激光LASIK术的安全性研究提供理论依据。

方法：选取2014-06/2016-06于我院行手术治疗的85例170眼近视患者,所有患者均采用飞秒激光LASIK术治疗,对符合纳入标准的病历资料进行回顾性分析。术前和术后3、6mo采用眼反应分析仪测量角膜补偿眼压(corneal compensated intraocular pressure,IOPcc)、角膜阻力因子(corneal resistance factor,CRF)、角膜滞后量(corneal hysteresis,CH)以及模拟Goldmann眼压(Goldmann correlated IOP value,IOPg),采用A型超声测量仪测量中央角膜厚度。

结果：术后3、6mo中央角膜厚度显著低于术前,差异有统计学意义(P<0.05); 术后3、6mo时IOPcc、CRF、CH、IOPg等角膜生物力学指标均显著低于术前,差异有统计学意义(P<0.05); 术后3、6mo各指标比较,差异无统计学意义(P>0.05); 角膜切削厚度为98.67±7.56μm,CH和CRF变化量分别为3.40±0.34mmHg、3.55±0.43mmHg,角膜切削厚度与CH、CRF变化量呈明显正相关(r=0.232、0.254,P<0.001)。

结论：飞秒激光LASIK术后角膜厚度显著降低,术后各项角膜生物力学指标均显著下降,且3mo后基本趋于稳定。     

近视眼手术人群角膜直径的分析

目的：测量近视眼手术人群的角膜直径,探讨不同性别、眼别角膜直径的差别及角膜直径与等效球镜度数之间的相关性。

方法：对2013-03/08来我院近视门诊行准分子激光手术的近视眼126例252眼,男48例96眼,女78例156眼, 年龄18～45(平均24.23±5.35)岁,应用IOL Master测量角膜直径\〖white-to-white(WTW)\〗距离。对252眼都采用NIDEK RT-2100综合验光仪进行主觉验光,并换算成等效球镜\〖Spherical equivalent(SE)\〗,按照等效球镜度数分成3组：轻度近视(-3.00D结果：全部病例角膜直径平均值为11.52±0.41mm,其中男性角膜直径11.60±0.35mm,女性11.43±0.36mm,性别间角膜直径有统计学意义( t=0.021,P=0.009); 右眼平均角膜直径(11.53±0.40mm)与左眼(11.51±0.42mm)比较无显著统计学差异(t=-0.115,P=0.912); 低度、中度和高度近视者的角膜直径的平均值分别为11.59±0.39、11.48±0.40、11.45±0.41mm,角膜直径与屈光度间呈负相关性(R²=-0.001,P=0.001),且三组近视患者角膜直径之间存在显著统计学差异(F=4.487, P=0.004)。

结论：近视眼手术人群中男性角膜直径大于女性; 近视程度越高,角膜直径越短。     

机械刀前弹力层下角膜磨镶术后角膜混浊的相关因素分析

目的：筛选引起机械微角膜刀前弹力层下角膜磨镶术(sub-Bowman keratomileusis,SBK)后角膜混浊的相关因素,为优化SBK术后效果提供参考。

方法：回顾性病例研究。法国Moria公司OUP90刀头制瓣的SBK术后896眼,术后3mo复查,记录有无角膜混浊。根据角膜混浊与否分为两组,对两组性别、年龄、术前眼压、术前角膜中央厚度、K₁、K₂、平均角膜曲率、术前等效球镜值进行统计学分析。

结果：角膜混浊组男52眼,女48眼,年龄(24.5±6.1)岁,眼压(14.26±2.24)mmHg,角膜中央厚度(487.27±18.52)μm,K₁ (44.24±1.23)D,K₂(43.33±1.13)D,平均曲率(43.79±1.15)D,等效球镜度(-4.65±1.44)D; 角膜无混浊组男412眼,女384眼,年龄(24.3±5.8)岁,眼压(16.72±7.01)mmHg,角膜中央厚度(533.11±28.74)μm,K₁(43.90±1.47)D,K₂(42.88±1.35)D,平均曲率(43.39±1.37)D,等效球镜度(-5.04±1.96)D; 两组中性别(χ²=0.002,P=0.964)、年龄(t=0.404,P=0.686)、等效球镜度(t =1.949,P=0.052)差异无统计学意义; 而术前眼压(t=-3.486,P=0.001)、术前角膜中央厚度(t=-15.543,P=0.000)、K₁(t =2.249,P=0.025)、K₂(t =3.172,P=0.002)及平均角膜曲率(t =2.763,P =0.006)差异有统计学意义。

结论：术前中央角膜薄、眼压低、角膜曲率高者机械刀SBK术后角膜混浊发生率高,性别、年龄、术前屈光度与机械刀SBK术后角膜混浊无关。     

健康人角膜滞后量和阻力因子量测量值及相关因素分析研究

目的 探讨健康人角膜滞后量和阻力因子量测量值及其与中央角膜厚度、角膜曲率、等效球镜度数及眼压之间的相互关系.方法 横断面研究.每名研究对象任选一眼的检测数据进行分析,共计205只眼.眼反应分析仪测量角膜滞后量和阻力因子量,并用多重回归分析其与中央角膜厚度、角膜曲率、等效球镜和眼压之间的相互关系.结果 205只眼的角膜滞后量和阻力因子量呈正态分布,两者集中分布在8.1～11.0 mm Hg(1 mm Hg=0.133 kPa)之间.在不同性别以及年龄(<25岁和≥25岁)组间的角膜滞后量和阻力因子量差异均无统计学意义(P>0.05).205只眼角膜滞后量和阻力因子量的95%参考值范围分别是6.8～13.0和6.6～13.6 mm Hg.角膜滞后量和阻力因子量与中央角膜厚度、角膜曲率、等效球镜度数及眼压相关(P<0.05).结论 角膜滞后量和阻力因子量分别描述了角膜生物力学特性中的不同属性,两者可能是对角膜厚度、曲率、硬度、水化状态、眼压等因素作用效力的综合体现.本文测定了正常人眼角膜滞后量和阻力因子量值,为今后进一步研究角膜滞后量和阻力因子量与眼病之间的关系奠定了基础.(中华眼科杂志,2008,44:715-719)     

低浓度阿托品联合角膜塑形镜矫治近视的临床观察

目的：观察低浓度阿托品滴眼液联合角膜塑形镜治疗青少年低中度近视的有效性及安全性。

方法：选取2016-05/2018-08于我院就诊的青少年低中度近视患者126例126眼(均取右眼数据),使用夜戴型角膜塑形镜1mo后随机进行分组,试验组患者63眼每晚联合应用低浓度(0.01%)阿托品滴眼液1次,对照组患者63眼每晚联合应用聚乙二醇滴眼液1次。随访观察眼轴、等效球镜度、最佳矫正近视力、瞳孔直径、调节幅度、泪膜破裂时间、眼压的情况。

结果：联合治疗1a,试验组和对照组低度近视患者眼轴分别增长0.13±0.03、0.22±0.05mm,中度近视患者眼轴分别增长0.12±0.03、0.20±0.05mm; 低度近视患者等效球镜度分别增加0.16±0.07、0.21±0.08D,中度近视患者等效球镜度分别增加0.16±0.05、0.20±0.09D,两组之间眼轴和等效球镜度变化均有差异(均P<0.05)。治疗1a后,两组患者最佳矫正近视力、泪膜破裂时间、眼压均无差异(P>0.05),但试验组患者瞳孔直径较对照组明显增大,调节幅度较对照组降低(P<0.05)。

结论：0.01%阿托品滴眼液联合角膜塑形镜能更有效控制青少年近视进展,且安全有效。     

LASIK术后不同时间应用噻吗洛尔对高度近视屈光回退的影响

目的：观察LASIK术后不同时间应用噻吗洛尔对高度近视患者屈光回退的影响。

方法：前瞻性研究。选取2015-08/2016-08收入我院的高度近视患者90例180眼为研究对象,随机分为对照组和观察组,各45例90眼,两组患者术后均常规使用抗生素滴眼液7d,对照组患者于术后第8d开始使用噻吗洛尔滴眼液,观察组患者于术后第1d开始使用噻吗洛尔滴眼液。分别于术前、术后7d,1、3、6mo检测并比较两组患者裸眼视力、等效球镜度、眼压、角膜表面曲率、角膜基质厚度。

结果：术后不同时间点两组患者裸眼视力、等效球镜度均有差异(P<0.05),且术后6mo,观察组患者裸眼视力、等效球镜度均优于对照组(0.03±0.01 vs 0.08±0.01; 0.15±0.33D vs -0.17±0.36D; 均P<0.05)。术后不同时间点两组患者角膜基质厚度和角膜表面曲均无组间差异性(P>0.05)。术后7d,1、3mo观察组患者眼压均明显低于对照组(均P<0.05),术后6mo两组患者眼压趋于稳定。

结论：LASIK术后早期应用噻吗洛尔能有效降低眼压,并保持相对较长时间眼压稳定,阻止角膜膨隆,进而起到预防屈光回退的效果。     

SMILE手术中角膜切削厚度精确性的研究

目的：评估不同程度近视患者SMILE术前预估角膜切削厚度与术后实际角膜切削厚度的差异,探究SMILE术中角膜基质切削厚度的精确性。

方法：前瞻性研究。收集2017-01/2019-08在我院行SMILE手术的近视患者143例234眼,根据术前等效球镜度分为低(-0.50～-3.00D,78眼)、中(>-3.00～-6.00D,78眼)、高(>-6.00D,78眼)度近视组,观察三组患者手术前后视力和等效球镜度,并分别于术前和术后1mo采用Pentacam眼前节综合分析系统测量中央角膜厚度,比较术前预估角膜切削厚度与术后1mo实际切削厚度的差异,探讨SMILE术中不同屈光状态角膜基质切削厚度的精确性。

结果：术后1mo,所有患眼裸眼视力均达0.8以上,98.3%患眼裸眼视力达1.0以上。所有患者术后1mo角膜平均实际切削厚度低于平均预估切削厚度(84.92±23.15μm vs 100.07±26.83μm,P<0.01),平均切削差异值为15.15±10.34μm。低、中、高度近视组患者角膜实际切削厚度均低于各组预估角膜切削厚度(P<0.01),切削差异值分别为8.81±7.78、15.59±9.27、21.05±10.03μm。术前,本研究纳入患者平均等效球镜度为-4.85±2.15D,术前等效球镜度与切削差异值之间具有直线回归关系(Y=-2.2495X+3.9287,R²=0.1589),等效球镜度数越大,切削差异值越大(t=-6.620,P<0.001)。

结论：SMILE手术的角膜基质实际切削厚度低于预估切削厚度,且近视度数越高,切削差异越大,但术后屈光矫正效果理想,术中角膜切削厚度的差异并不影响屈光矫正手术的精确性。     

SMILE对不同曲率近视患者的疗效及其影响因素分析

目的：分析飞秒激光小切口角膜基质透镜取出术(SMILE)治疗不同曲率近视患者的疗效及其影响因素。

方法：前瞻性纳入行SMILE的近视患者72例144眼,按照术前角膜曲率分为低曲率组(<41D,21例42眼)、中曲率组(41～46D,26例52眼)、高曲率组(>46D,25例50眼)。比较各组术前和术后1wk,3mo屈光状态、裸眼视力(UCVA)、最佳矫正视力(BCVA)、角膜光学质量的改变情况,筛选近视眼患者SMILE视力恢复的影响因素。

结果：三组患者组内手术前后不同时间UCVA、BCVA比较有差异(P<0.05),组间不同时间比较无差异(P>0.05)。三组术后不同时间球镜度数、柱镜度数、等效球镜度数比较无差异(P>0.05)。三组主观验光屈光力矢量变化值比较有差异(P<0.05),低曲率组主观验光屈光力矢量变化值低于中曲率组、高曲率组(P<0.05)。多元Logistic回归分析显示：年龄、眼轴长度、术前等效球镜度均为影响SMILE手术疗效的相关因素(P<0.05)。

结论：SMILE对不同曲率近视患者视力均有较好的改善作用,安全有效。年龄、眼轴长度、术前等效球镜度均为影响SMILE术后视力的相关因素。     

新型非接触式眼压分析仪ORA与Goldmann压平眼压计的比较

目的比较新型非接触式眼压分析仪ORA与Goldmann压平式眼压计测量眼压的差异,以评价ORA眼压测量仪在临床眼压测量中的应用价值。方法本院门诊127例237眼分别由专人进行非接触眼压测量仪ORA与Goldmann压平式眼压计测量,并同时用超声角膜测厚仪测量角膜厚度。结果127例病人237眼,Goldmann压平眼压值和ORA直接测量结果（IOPG）分别为（17.94±6.50）mmHg和（18.88±7.93）mmHg,两者比较差异有显著统计学意义（P=0.000）;正常人群平均角膜厚度为（546.19±36.34）μm,经角膜厚度-眼压公式校正IOPG平均值为17.42±3.92mmHg,ORA经自带软件处理后的眼压值（IOPcc）平均为（17.50±4.38）mmHg,两者比较差异无统计学意义（P=0.681）,IOPG校正前两者比较差异有统计学意义（P=0.024）。结论新型非接触式眼压分析仪ORA的直接测量值与Goldmann压平眼压计的测量值相近略高,ORA的测量分析值IOPcc是排除角膜因素影响更接近真实的眼压结果。     

Age-related change in corneal biomechanical parameters in a healthy Caucasian population

Purpose: To determine the effect of aging on corneal biomechanical parameters measured via ocular response analyzer in a homogenous healthy Caucasian population.

Methods: A total of 2039 Caucasian adults were consecutively recruited and divided into seven groups according to decades of age. The difference in mean corneal hysteresis (CH), mean corneal resistance factor (CRF), mean Goldmann-correlated intraocular pressure (IOPg), and mean corneal-compensated IOP (IOPcc) between decades of age were investigated. The strength of the correlations between corneal biomechanical parameters, and between each biomechanical parameter and age were evaluated. The effect of age on each corneal biomechanical parameter was analyzed.

Results: Mean age of the participants (1173 female and 866 male) was 43.30 ± 14.64 years. Mean CH, CRF, IOPcc, and IOPg were 11.49 ± 1.89 mmHg, 11.40 ± 2.30 mmHg, 15.01 ± 3.11 mmHg, and 15.72 ± 3.80 mmHg, respectively. There were significant differences in mean CH, CRF, IOPcc, and IOPg between groups (p < 0.001 for all parameters). There was a significant negative correlation between age and CH (r = –0.067 and p = 0.003), and a significant negative correlation between age and CRF (r = –0.053 and p = 0.017). There was a significant positive correlation between age and IOPg (r = 0.25 and p < 0.001), and between age and IOPcc (r = 0.20 and p < 0.001). Linear regression analysis showed that for every 1-year increase CH decreased 0.011 mmHg, CRF decreased 0.004 mmHg, IOPcc increased 0.053 mmHg, and IOPg increased 0.047 mmHg.

Conclusions: Aging can cause significant changes in corneal biomechanical parameters. Corneal biomechanical parameters were correlated with each other, and each was correlated with aging.     

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.     

Effect of pathological myopia on biomechanical properties: a study by ocular response analyzer

AIM: To evaluate the ocular response analyzer (ORA) measurements of patients with pathological myopia in comparison with those of emmetropic control subjects, and to investigate the correlation between these ORA measurements and spherical equivalent (SE). METHODS: Measurements of 53 eyes of 53 subjects with pathological myopia (SE>-6.00 D) were compared with those of 60 eyes of 60 emmetropic controls. Corneal hysteresis (CH), corneal resistance factor (CRF), noncontact tonometer intraocular pressure (IOPg), and corneal-compensated IOP (IOPcc) were obtained for each subject. The refractive error value was determined as SE via a cycloplegic refraction test. RESULTS: The mean age was 54.1±18.9y (ranging from 5 to 88) in the pathological myopic group and 56.2±19.0y (ranging from 6 to 89) in the control group. There were no significant differences between the groups concerning age and sex. CH and CRF were significantly lower in the pathological myopic group than in the control group (P<0.001, P=0.005, respectively). IOPcc and IOPg were significantly higher in the pathological myopic group than in the control group (P<0.001, P=0.009, respectively). There were significantly positive correlations between CH and SE (r=0.565, P<0.001) and between CRF and SE (r=0.364, P=0.007). There were significantly negative correlations between IOPcc and SE (r=-0.432, P=0.001) and between IOPg and SE (r=-0.401, P=0.003). CONCLUSION: The present study displayed that pathological myopia affected biomechanical properties measured by ORA. The results of corneal biomechanical properties measured by ORA may need to be appreciated by taking refraction into account. Further, pathological myopia might be related with the increased IOP.     

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%.     

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。     

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 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   

Relationship Between Corneal Hysteresis and Corneal Resistance Factor with Other Ocular Parameters

Abstract

Purpose: To evaluate the relationship between corneal hysteresis (CH) and corneal resistance factor (CRF) with age, central corneal thickness (CCT), corneal curvature (KM), corneal volume (CV), and refractive error in naïve eyes. Methods: 105 healthy subjects (58 male and 47 female) were included in this study. The ages ranged from 19 to 82 years (mean 43.1?±?15.4 years) and refraction between ?11?D and +6?D (mean ?0.79?±?2.95?D). CH and CRF obtained with the Ocular Response Analyzer (ORA) were correlated with age, refractive error, Goldmann Applanation Tonometry (GAT), and with CCT, KM, CV obtained with the Pentacam, and with Corneal-Compensated Intraocular Pressure (IOPcc) and Goldmann-correlated intraocular pressure measurement (IOPg) obtained with ORA. A multivariable mixed effect model was used to evaluate associations among these parameters. Results: CH ranged from 6.9 to 14.6?mmHg (mean 10.26?±?1.49?mmHg); CRF ranged from 5.8 to 17?mmHg (mean 10.38?±?1.64?mmHg). Multivariate analysis showed a statistically significant correlation between CH with CCT (p?<?0.001), and KM (p?<?0.001), and between CRF with CCT (p?<?0.001) and GAT (p?<?0.001). Conclusions: Our findings support the hypothesis that CH and CRF are related to the corneal shape and thickness, and show a decrease of CH with age.     

Corneal biomechanics measured with the ocular response analyser in patients with unilateral open‐angle glaucoma

Purpose: To evaluate the relationship between biomechanical properties of the cornea and intraocular pressure (IOP) and the role of biomechanical properties in eyes of patients with unilateral primary open‐angle glaucoma (POAG). Methods: The biomechanical properties of corneal hysteresis (CH) and the corneal resistance factor (CRF) were measured with the ocular response analyser (ORA). In an experimental setting, three human donor eyes with Schiotz‐tonometry‐controlled IOP were investigated. In addition, a series of patients with unilateral POAG were evaluated. Main outcome measures were CH, CRF, corneal‐compensated IOP (IOPcc), standard automated perimetry parameters mean defect (MD) and pattern standard deviation, central corneal thickness, Goldmann applanation tonometry (GAT), and cup‐to‐disc ratio. Results: A highly significant linear correlation between CH and the corneal‐compensated IOP (IOPcc, r = ?0.926; p < 0.001) was found. The correlation between IOP_CC and CRF was not significant (r = 0.335; p = 0.08). In total, 36 eyes of 18 patients with unilateral POAG were examined. Regarding uncorrected CH (mean 7.73 ± 1.46 mmHg glaucomatous eye and 9.28 ± 1.42 mmHg fellow eye), there was a highly significant difference between both eyes. This difference disappears, when CH was corrected for IOP (9.44 ± 3.78 mmHg and 9.97 ± 3.22 mmHg, respectively). Conclusions: Corneal hysteresis but not corneal resistance factor is dependent on IOP. In patients with unilateral POAG, IOP is higher in the affected eye. When CH is corrected for IOP, corneal biomechanical properties do not differ in both eyes of patients with unilateral POAG.     

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.