中央角膜厚度对3种眼压计眼压测量值的影响

目的比较分析不同中央角膜厚度(central corneal thickness,CCT)下Icare回弹式眼压计、Goldmann压平式眼压计(Goldmann applanation tonometer,GAT)和动态轮廓眼压计(dynamic contour tonometry,DCT)的眼压测量结果,探讨CCT对3种眼压计测量值的影响。方法 对78例患者152眼分别用Icare、GAT、DCT3种眼压计进行眼压测量,并进行CCT的测量,对比不同CCT下3种眼压计的测量结果,分析眼压测量值与CCT的关系。结果 在全部受测者中Icare、GAT、DCT测得的眼压均值分别为(19.16±5.03)mmHg(1 kPa=7.5 mmHg)、(18.41±4.52)mmHg和(17.23±3.69)mmHg,三者之间有显著差异(F=7.256,P=0.001)。Icare和GAT的眼压测量值均与CCT显著相关(r=0.341,P<0.001;r=0.333,P<0.001),CCT每改变10μm,Icare的眼压值改变0.47 mmHg,GAT的眼压值改变0.41 mmHg;而DCT的眼压测量值与CCT无显著相关(r=0.032,P=0.699)。结论 Icare、GAT的眼压测量值均明显受CCT的影响,而Icare受CCT影响的程度较GAT的稍大,DCT的眼压测量值基本不受CCT的影响。     

青光眼患者角膜中央厚度与眼压关系的Meta分析

目的：系统回顾正常人群和青光眼患者中央角膜厚度与眼压的研究资料,探讨两者之间的关联与机制。
　　方法：在MEDLINE数据库和Science Direct数据库搜索有关角膜中央厚度与眼压关系的研究资料。另外在南方医科大学外文科部搜索2004/2006“眼科年刊”期刊。搜索
　　关键词包括：角膜中央厚度、眼压、青光眼、高眼压症、剥脱青光眼、压平眼压计、厚度测量法、原发性开角青光眼、Goldmann压平眼压计。应用以下排除标准：1)非英语文献研究;2)在2005年以前的研究;3)案例性研究和案例点评性研究;4)与治疗方案或外科手术技术有关的研究;5)将青光眼与其他疾病,如糖尿病、高血压、心血管疾病来比,作为辅助变量;6)儿童作为研究对象的研究;7)动物作为研究对象的研究。
　　结果：搜索产生了13项研究,包括12个观察性研究和1个病例对照研究。与对照组相比,青光眼患者眼压水平明显升高( SMD：0.50,95% CI：0.30~0.70, Z=4.88, P<0.001);青光眼组患者角膜中央厚度水平有明显降低(SMD：-0.14,95% CI：-0.23~-0.05, Z=3.14, P=0.002)。 Meta-回归分析结果显示年龄跟两个组之间观察到的 CCT 差异有统计学意义( P=0.025)。
　　结论：与正常眼组相比,青光眼组患者表现为角膜中央厚度变薄和眼压增高。     

正常人中央角膜厚度与Goldmann压平眼压的关系

目的:了解正常人中央角膜厚度(central corneal thickness,CCT)的分布特点并探讨其与压平眼压测量值的关系。方法:采用光学角膜测厚仪及Goldmann压平眼压计检测169名正常人CCT和压平眼压。结果:169名受检者右眼平均CCT为0.547mm(95%可信区间0.443~0.651mm),左眼0.551mm(95%可信区间0.453~0·649)。压平眼压右眼平均15.8mmHg,左眼15.5mmHg。CCT与年龄无相关关系,但与压平眼压测量值显著相关。线性回归分析表明,CCT每增加0.018mm,压平眼压增加1mmHg。结论:CCT变异是眼压测量误差的主要来源。CCT较厚的正常个体可表现"眼压增高"被误诊为高眼压症,而CCT偏薄的原发性开角型青光眼患者则可能因眼压测量"正常"被误诊为正常眼压性青光眼。在诊断青光眼或高眼压症时,特别是在眼压值与其他临床表现不符时,应考虑CCT有无变异。     

中央角膜厚度的测量及其影响因素

自从1880年Blix第1次用光学方法测量中央角膜厚度(central corneal thickness，CCT)以来．由于临床和科研工作的需要，尤其是Goldmann压平眼压计的应用和屈光性角膜手术的开展，角膜厚度的测量越来越被人们所重视。本文就CCT的测量方法、测量值及其影响因素作一综述。     

不同角膜厚度下动态轮廓眼压计和Goldmann压平眼压计在不同角膜厚度的测量值比较

目的比较动态轮廓眼压计（dynamic contour to-nometry,DCT）和Goldmann压平眼压计（Goldmann applanation tonometry,GAT）在中央角膜厚度（central corneal thickness,CCT）不同的正常眼测量值的差异。方法患者69例（69眼）按CCT不同分为正常组（520～580μm）42眼、变薄组（450～520μm）16眼、增厚组（580～640μm）11眼。各组分别用DCT和GAT测量眼压。结果正常组平均CCT为（574.55±16.40）μm,平均GAT值为（16.62±3.15）mmHg（1kPa=7.5mmHg）,平均DCT值为（16.78±2.86）mmHg,DCT与GAP差异无统计学意义（P〉0.05）,平均GAT-DCT值为（-0.16±0.96）mmHg;变薄组平均CCT为（499.44±16.70）μm,平均GAT值为（14.03±2.72）mmHg,平均DCT值为（17.06±2.72）mmHg,2者差异有统计学意义（P〈0.01）,平均GAT-DCT值为（-3.03±1.32）mmHg;增厚组平均CCT为（605.18±17.90）μm,平均GAT值为（16.91±3.94）mmHg,平均DCT值为（16.80±4.25）mmHg,2者差异无统计学意义（P〉0.05）,平均GAT-DCT值为（0.05±2.47）mmHg。结论在角膜厚度正常眼,DCT值和GAT值较一致;在角膜厚度变薄眼,前者较后者准确;在角膜厚度变厚眼未体现DCT的优越性。     

角膜厚度对三种不同眼压计测量的影响

目的:比较采用Goldmann压平眼压计(Goldmann applanation tonometer,GAT)、非接触眼压计(non-contact tonometer,NCT)和Schiotz眼压计(Schiotz tonometer,ST)的眼压(intraoeular pressure,IOP)测量,评估角膜中央厚度(central corneal thickness,CCT)对读数的影响。方法:使用GAT、NCT和ST对所有患者的右眼进行眼压测量。超声角膜厚度测量法测定CCT。所有IOP及CCT测量由同一检查者进行。计算CCT25%(Q1)百分位数和75%(Q3)百分位数值,并通过这种方法将该组分为薄、中、厚角膜亚组。使用Statplus软件进行统计分析。结果:全系列144眼,GAT测量平均IOP为17.4±4.9mmHg,NCT为16.0±5.8mmHg,ST为14.0±4.0mmHg(Friedman方差分析P<0.01)。IOP水平和CCT之间的相关系数NCT为0.787(P<0.01),GAT为0.630(P<0.01),ST为0.565(P<0.01)。ST测量中,纠正的IOP误差和CCT之间的相关性在厚角膜明显弱(r=0.381,P=0.022)。结论:NCT是最易受不同CCT影响的设备。ST读数似乎比GAT和NCT读数受CCT的影响小。特别是在厚角膜,与NCT和GAT相比,ST可以被认为是一个更可靠的仪器。     

非接触式眼压计与Goldmann压平眼压计测量眼压的比较

目的 :比较非接触式眼压计 ( NCT)和 Goldm ann压平眼压计测量眼压的差异。方法 :对 112例 ( 2 2 0眼 )志愿者分别进行 NCT和 Goldmann压平眼压计眼压测量及中央角膜厚度测量 ,并对其中 16 8眼进行自动验光检查。结果 :NCT和 Goldmann眼压计眼压测量值分别为 1.98± 0 .6 9k Pa和 2 .34± 0 .77k Pa。 NCT眼压测量值较 Goldmann眼压测量值偏低 0 .36± 0 .37k Pa( P<0 .0 5 )。眼压在 1.33～ 2 .6 7k Pa内 ,二种眼压计测量眼压值偏差最小。角膜厚度和眼球屈光度与 NCT眼压测量值分别呈明显正相关和负相关。结论 :NCT眼压测量值较Goldmann眼压测量值偏低 ,NCT眼压值为临界眼压时 ,应应用 Goldm ann压平眼压计校正     

PASCAL动态轮廓眼压计与Goldmann压平眼压计在非青光眼人群中眼压测量值的比较及一致性分析

目的探讨在不同的中央角膜厚度(CCT)下PASCAL动态轮廓眼压计(DCT)与Goldmann压平眼压计(GAT)眼压(IOP)测量值的相关性,评价两者测量值的一致性及临床上两种眼压计测量值相互替换的可能性。方法非青光眼病例87例(168只眼)分别用DCT和GAT进行眼压测量,两种仪器的测量顺序随机。同时,用NIDEK UP-1000型角膜测厚仪测量CCT。DCT与GAT眼压测量值的相关性采用Spearson双变量相关分析,Bland-Altman分析法评价两种仪器IOP测量值的一致性。结果 (1)在不同的角膜厚度下DCT与GAT测得的IOP值均显著相关(CCT≤520μm,n=24,r=0.67,P<0.001;520μm580μm,n=44,r=0.61,P<0.001)。(2)DCT眼压测量值与CCT不相关(r=0.14,P=0.08),GAT眼压测量值与CCT显著相关(r=0.59,P<0.001)。(3)Bland-Altman一致性分析显示两种仪器的差值的均值为-0.9mm Hg,一致性界限为(-5.6 mm Hg,3.9 mm Hg)。结论 (1)在不同的角膜厚度下DCT与GAT的眼压测量值均显著相关。(2)DCT眼压测量值与CCT值不相关,GAT眼压测量值与CCT值显著相关。(3)一致性分析显示两者测量值的一致性界限跨度较宽,二者的IOP值不可简单地相互代替。     

Corvis ST与常用眼压计及角膜测厚仪在测量眼压及角膜厚度中的应用

目的：比较可视化角膜生物力学分析仪（Corvis ST）与三维眼前节分析仪（Pentacam）、非接触式眼 压计（NCT）、A型超声角膜测厚仪（A超）、光学生物眼科测量仪（Lenstar）在测量眼压及中央角膜 厚度的差异。方法：前瞻性研究。纳入2020年8—12月佛山市第二人民医院屈光术前近视患者110 例,将Corvis ST 眼压（IOP）及校正眼压（BIOP）、NCT眼压与Pentacam对NCT的校正眼压纳入眼压 指标;将Corvis ST的中央角膜厚度、Pentacam的最薄点中央角膜厚度、Lenstar的角膜厚度、A超的 角膜厚度纳入角膜厚度指标。眼压与角膜厚度的差异对比采用单因素方差分析法,相关性分析采 用Pearson方法,一致性检验采用Bland-Altman。结果：眼压：Corvis ST分别与NCT、Pentacam所测 量的眼压值在组间比较差异无统计学意义,其中Corvis ST分别与NCT、Pentacam测量的眼压值比 较差异有统计学意义（P=0.019; P=0.03）。IOP与NCT眼压、Pentacam校正眼压呈正相关性（r=0.76, P ＜0.001; r=0.65, P＜0.001）,BIOP与NCT眼压、Pentacam校正眼压呈正相关性（r=0.66, P＜0.001; r=0.69, P＜0.001）,IOP与BIOP呈高度正相关性（r=0.92, P＜0.001）。IOP与NCT眼压、Pentacam校 正眼压、BIOP的95%一致性界限与最大差值绝对值分别为（-2.8~4.3 mmHg, 3.8 mmHg）、（-3.1~4.5 mmHg, 4.1 mmHg）、（-1.46~1.97 mmHg, 1.9 mmHg）,BIOP与NCT眼压、Pentacam校正眼压的95%一 致性界限与最大差值绝对值分别为（-3.6~4.6 mmHg, 4.2 mmHg）、（-3.0~3.9 mmHg, 3.4 mmHg）。中 央角膜厚度：Corvis ST与A超、Lenstar、Pentacam所测量的中央角膜厚度值在组间比较差异有统计 学意义（F=2.67, P=0.046）,其中Corvis ST与A超的差异有统计学意义（P=0.017）。Corvis ST与A超、 Lenstar、Pentacam所测量的中央角膜厚度值存在着高度正相关性（r=0.96, P＜0.001; r=0.98, P＜0.001; r=0.98, P＜0.001）。Corvis ST与A超、Lenstar、Pentacam对中央角膜厚度的测量值的95%一致性界限 与最大差值绝对值分别为（-5.9~24.3 μm, 23 μm）、（-6.4~18.7 μm, 18 μm）、（-10.7~12 μm, 11 μm）。结 论：Corvis ST的眼压测量值与NCT、Pentacam不可相互替代,并且Corvis ST的BIOP更接近真实眼压; Corvis ST的CCT测量值与A超、Lenstar不可相互替代,与Pentacam可相互替代。     

动态轮廓眼压计与眼压测量

五十年来,Goldmann压平眼压计(Goldmann applanation tonometer,GAT)一直被认为是眼压(introcular pressure,IOP)测量的"金标准",很少有临床医生关注它的局限性。其实早在20世纪50年代GAT发明时,Goldmann就明确指出了自己设     

Effects of central corneal thickness,central corneal power,and axial length on intraocular pressure measurement assessed with goldmann applanation tonometry

Purpose  To determine the effects of central corneal thickness (CCT), central corneal power (CCP), and axial length (AL) on the measurement of intraocular pressure (IOP) using Goldmann applanation tonometry, and the effects of CCP and AL on CCT. Methods  Charts of 147 consecutive patients undergoing preoperative examinations for cataract surgery between April 2006 and April 2007 in our clinic were reviewed retrospectively. CCT, CCP, and AL were measured by ultrasonic pachymeter (Micropach Model 200P, Sonomed, Lake Success, N.Y. USA), autorefractokeratometer (KR 8800, Topcon, Tokyo, Japan), and ultrasound biometry (EZ Scan AB 5500+ Sonomed, Lake Success, N.Y. USA). Pearson correlation analysis and multiple linear regression analysis were used as indicated, and only one eye of each subject was included in the statistical analysis. Results  Ninety-eight eyes of 98 patients were included in the study. IOP and CCT were significantly and positively correlated (P < 0.001), and CCT and CCP (P = 0.001) were inversely correlated. Multiple regression analysis showed that the effect of CCT on IOP was statistically significant (P < 0.001), but the effects of CCP and AL on IOP were not significant (P = 0.614, P = 0.831, respectively). IOP increased by 0.29 mmHg for each 10 μm increase in CCT. Conclusions  CCT, but not CCP or AL, significantly affected IOP readings obtained by Goldmann applanation tonometry. The effect of CCP on IOP was weak and not significant despite the significant inverse correlation between CCT and CCP.     

Effects of corneal thickness on intraocular pressure measured with three different tonometers

Purpose: To compare intraocular pressure (IOP) measured by a Goldmann applanation tonometer (GAT), a noncontact tonometer (NCT), and a portable noncontact tonometer (PNCT) in eyes of healthy volunteers, and to determine if a significant correlation exists between the IOP and the central corneal thickness (CCT). Methods: A total of 144 healthy participants were randomly assigned to one of two groups; in the first group, IOP was measured first with the NCT and then with the GAT. In the second group, IOP was measured first with the PNCT and then with the GAT. Subsequently, the CCT of all subjects was measured with an ultrasonic pachymeter. Results: The IOPs determined by the GAT and NCT and were strongly correlated, as were those determined by the GAT and PNCT, in both groups. However, a Bland-Altman plot showed that the correlations between the GAT and NCT and between the GAT and the PNCT measurements were not significant. With all three instruments, the IOP readings varied with the CCT. The mean IOPs obtained with the GAT increased by 0.23 mmHg with each 10-μm increase in CCT (0.23 mmHg/10 μm). The comparable value for the NCT was 0.29 mmHg/10 μm, and that for the PNCT was 0.31 mmHg/10 μm. Conclusions: For measurements of IOP in normal eyes, the GAT is the tonometer least affected by the CCT, compared with the PNCT and NCT. A PNCT is more likely to be affected by variations in CCT than the GAT.     

角膜厚度对两种眼压测量方法的影响

目的　比较非接触眼压计 (non -contacttonometer ,NCT)和Goldmann压平眼压计测量眼压的差异 ,并分别探讨中央角膜厚度 (centralcornealthickniss ,CCT)对这两种测量方法的影响。方法　对 1 0 8例拟接受PRK或LASIK手术的患者行CCT ,NCT和Goldmann压平计眼压测量。结果NCT和Goldmann压平眼压计测得的眼压均值具有显著性差异 (F =89 .70 4 4,P <0 . 0 1 )。CCT与NCT和Goldmann压平眼压计测量值呈正相关 ,相关系数分别是r =0. 4 96 0 (t =8 .356 3,P <0 .0 0 1 )和r =0 . 2 1 1 3(t =3. 1 6 2 3,P <0 .0 0 1 )。结论　NCT和Goldmann压平眼压计测量眼压值有差异 ,NCT测量值大于Goldmann压平眼压计 ,CCT对NCT的影响大于Goldmann压平眼压计。     

Dependence of dynamic contour and Goldmann applanation tonometries on peripheral corneal thickness

AIM: To determine the effects of peripheral corneal thickness (PCT) on dynamic contour tonometry(DCT) and Goldmann applanation tonometry (GAT). METHODS: A cross-sectional study. We created a software which calculates the corneal contour (CC) as a function of the radius from the corneal apex to each pixel of the contour. The software generates a central circumference with a radius of 1 mm and the remainder of the cornea is segmented in 5 rings concentric with corneal apex being its diameter not constant around the corneal circumference as a consequence of the irregular CC but keeping constant the diameter of each ring in each direction of the contour. PCT was determined as the mean thickness of the most eccentric ring. Locally weighted scatterplot smoothing (LOWESS) regression was used to determine the pattern of the relationship between PCT and both DCT and GAT respectively. Thereafter, two multivariable linear regression models were constructed. In each of them, the dependant variable was intraocular pressure (IOP) as determined using GAT and DCT respectively. In both of the models the predictive variable was PCT though LOWESS regression pattern was used to model the relationship between the dependant variables and the predictor one. Age and sex were also introduced control variables along with their first-degree interactions with PCT. Main outcome measures include amount of IOP variation explained through regression models (R2) and regression coefficients (B). RESULTS: Subjects included 109 eyes of 109 healthy individuals. LOWESS regression suggested that a 2nd-degree polynomial would be suitable to model the relationship between both DCT and GAT with PCT. Hence PCT was introduced in both models as a linear and quadratic term. Neither age nor sex nor interactions were statistically significant in both models. For GAT model, R2 was 17.14% (F=9.02; P=0.0002), PCT linear term B was -1.163 (95% CI: -1.163, -0.617). PCT quadratic term B was 0.00081 (95% CI: 0.00043, 0.00118). For DCT model R2 was 14.28% (F=9.29; P=0.0002), PCT linear term B was -0.712 (95% CI: -1.052, -0.372), PCT quadratic term was B=0.0005 (95% CI: 0.0003, 0.0007). CONCLUSION: DCT and GAT measurements are conditioned by PCT though this effect, rather than linear, follows a 2nd-degree polynomial pattern.     

不同角膜厚度下非接触眼压计与Schiotz眼压计测量眼压的比较

目的：比较不同角膜厚度下非接触眼压计与Schiotz眼压计测量结果的差异。 方法：对314例627眼分别用角膜测厚仪测量角膜厚度,非接触眼压计与Schiotz眼压计测量眼压,根据角膜厚度分为：较薄组（角膜厚度≤530μm）、正常组（530μm＜角膜厚度≤570μm）、较厚组（角膜厚度＞570μm）。采用配对t检验比较不同角膜厚度下两种测量结果的差异,并通过Bland-Altman进行一致性评价。 结果：角膜厚度较薄组170眼,正常组301眼,较厚组156眼。两种方法在较薄组、正常组、较厚组三组中的眼压值分别为12.82±2.67,12.84±2.37mmHg;13.67±2.66,1358±2.41mmHg;15.45±2.91,14.76±2.39mmHg。两种方法测量结果在角膜厚度正常和偏薄组中差异无统计学意义,偏厚组中差异有统计学意义。 结论：在角膜厚度≤570μm的人群中,眼压的检查可在非接触眼压计和Schiotz眼压计间选择一种检查;对于角膜厚度＞570μm的人群,需参考两种方法检查结果,进一步检查排除青光眼。     

Effect of corneal thickness on intraocular pressure measurements with the Pascal dynamic contour,Canon TX‐10 non‐contact and Goldmann applanation tonometers in healthy subjects

Purpose: To investigate the effects of central corneal thickness (CCT) on intraocular pressure (IOP) measurements of the Pascal dynamic contour tonometry (DCT), Canon TX‐10 non‐contact tonometry (NCT) and Goldmann applanation tonometry measurements (GAT) in healthy subjects. Methods: IOP values of 135 eyes with normal corneas of 135 healthy volunteers were determined by DCT, NCT and by GAT. The CCT was measured using an ultrasonic pachymeter after all IOP determinations had been made. Results: When DCT measurements were compared (IOP = 17.52 ± 2.0 mmHg) with NCT measurements (IOP = 16.54 ± 2.77 mmHg) and GAT measurements (IOP = 15.07 ± 2.35 mmHg), DCT measurements were significantly higher than NCT and GAT (p < 0.001). There was a significant correlation between CCT with both NCT (r = 0.260, p = 0.003) and GAT measurements (r = 0.257, p = 0.005). There was a weak correlation that was not statistically significant between CCT and DCT (r = 0.160, p = 0.079). Conclusion: The IOP measurements with DCT seem to be less dependent on CCT. NCT appears to be more affected by variation in CCT than GAT.