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。     

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。     

不同角膜厚度下Pentacam系统对压平眼压计测量值的校正

目的 比较Goldmann压平眼压计(Goldmann applanation tonometry,GAT)和Pentacam眼压校正系统在中央角膜厚度(central corneal thickness,CCT)不同的正常眼测量值的差异,评价其校正准确性.方法 对69例(69只眼)按CCT不同,分为正常组(520～<580μm)42只眼、较薄组(450～<520μm)16眼、增厚组(580～640μm)11只眼.应用Pentacam前房分析仪检查和Goldmann压平眼压计测量眼压,并用Pentacam系统所提供的4种校正方法对眼压测量值进行校正.结果 角膜正常组和角膜增厚组中,平均GAT、各组眼压校正值之间差异均无统计学意义(P>0.05),GAT、各组眼压校正值与CCT之间无线性相关(P>0.05);角膜较薄组中,平均GAT、各组眼压校正值之间差异均有统计学意义(P<0.05),GAT值与CCT之间线性相关(IOP=0.067×CCT-16.582,r2=0.730,P<0.05),Shah组校正值与CCT之间亦存在线性相关(IOP=0.076×CCT-25.349,r2=0.328,P<0.05);其余各组与CCT之间无明显相关(P>0.05).结论 Pentacam三维眼前段分析仪根据角膜厚度校正眼压测量值,尤其对角膜较薄组使用Dresden校正公式,有助于对其诊断和治疗提供更加准确的依据.     

PASCAL动态轮廓眼压计临床应用的初步报告

目的:验证动态轮廓眼压计(DCT)的临床性能。方法:对81例143眼青光眼及可疑病例青光眼患者用DCT测量眼内压(IOP);132眼同时用Goldmann压平眼压计(GAT)测量眼压,部分病例同时用NIDEKUP-1000型角膜测厚仪测量中央角膜厚度(CCT)。GAT与DCT测量结果采用配对t检验,GAT、DCT测量值与CCT的关系及DCT测量值与眼脉动振幅(OPA)的相关关系采用Spearman双变量相关分析。结果:①DCT和GAT测得的眼压均数分别为(18.6±3.9)mmHg和(17.4±4.1)mmHg;DCT测得的眼压值高于GAT,其差值均数为(1.1±2.3)mmHg;两种眼压计测得的眼压值呈正相关(r=0.83,P<0.01)。②116眼同时完成了DCT眼压测量及CCT测量,两者相关系数r=0.03,P=0.77;113眼同时完成了GAT眼压测量及CCT测量,两者相关系数r=0.28,P=0.003。③143眼同时记录了DCT眼压值和眼脉动振幅(OPA),其均数分别为(18.6±3.9)mmHg和(2.6±1.1)mmHg,两者的相关系数r=0.32,P<0.01。结论:以上结果初步证实:①DCT眼压计测量值与GAT眼压测量值高度相关,但DCT测量值略高于GAT测量值,提示DCT可用于临床诊断。②DCT测量值与CCT不相关,GAT测量值与CCT显著相关,提示DCT在青光眼诊断中有独特优势。③DCT测量的OPA与IOP值显著相关,相关的机制及临床意义有待探讨。     

中央角膜厚度及屈光度对压平眼压计测量值的影响

目的 探讨中央角膜厚度(CCT)以及屈光状态对Goldmann压平眼压计(GAT)测量值的影响.方法 应用OCT3测量正常人121例(199只眼)与近视患者81例(159只眼)的CCT,用Goldmann压平眼压计测量眼压,比较两组之间CCT和眼压测量值的差异,分析CCT与眼压测量值的关系.结果 正视组平均CCT值为(525.05±32.83)μm,眼压的均值为(12.91±2.26)mmHg;近视组平均CCT值为(524.85±29.76)μm,眼压的均值为(14.23±2.54)mmHg;两组的CCT值比较差异无显著性(t=-0.600,P=0.952),两组的眼压值比较差异有显著性(t=-5.139,P＜0.001).高度近视眼CCT偏薄,眼压随屈光度数较少而增加,近视组眼压与屈光度相关(r=-0.296,P＜0.001),屈光度数每增加-4.05D,眼内压升高1 mmHg.正视组(r=0.317,P＜0.001)和近视组(r=0.341,P＜0.001)的眼压与CCT相关,眼压校正公式分别为1 mmHg/45.45 μm、1 mmHg/34.48 μm.结论 CCT可以影响Goldmann压平眼压计测量值,屈光状态也可以影响眼压值,高度近视眼的眼压建议用从近视人群中获得的眼压校正公式校正.     

动态轮廓眼压计在正常人群中的应用及其影响因素分析

目的评价动态轮廓眼压计（DCT）与Goldmann压平眼压计（GAT）测量值之间的关系,寻找DCT眼压测量值的影响因素;分析DCT所测眼压脉动振幅（OPA）与DCT眼压值、中央角膜厚度（CCT）、角膜屈光力（CCV）、眼轴长度（AL）、前房深度（ACD）、收缩压（SBP）、舒张压（DBP）和心率（HR）的关系。方法分别测量正常人60例60眼的DCT眼压、GAT眼压、CCT、CCV、AL、ACD以及HR、SBP、DBP等指标,比较GAT、DCT2种眼压计测量的相关性及DCT测量值的影响因素。结果 DCT与GAT所测眼压平均值分别为（16.04±2.57）mmHg和（14.20±2.93）mmHg。DCT眼压值较GAT眼压值高,差异有统计学意义（t=6.454,P〈0.01）。DCT眼压值与GAT眼压值呈正相关（r=0.684,P〈0.01）。DCT眼压值与CCT不相关（r=0.212,P=0.105）,GAT眼压值与CCT呈正相关（r=0.291,P=0.024）。60例正常人的OPA均值为（2.50±0.89）mmHg,OPA与年龄、DCT眼压值、CCT、SBP、DBP、HR均不相关（P〉0.05）,与CCV呈正相关（r=0.343,P=0.007）。结论在正常人群中DCT眼压值与GAT眼压值有较好的相关性,DCT的眼压测量值不受CCT、CCV等因素的影响。DCT眼压值、CCT、SBP、DBP、HR等对OPA无明显影响。     

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。     

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。     

轮廓动态眼压计测量准分子激光原位角膜磨镶术后眼压

目的通过与Goldmann眼压计(goldmann appla-nation tonometer,GAT)的比较,评价轮廓动态眼压计(dynamiccontour tonometer,DCT)在准分子激光原位角膜磨镶术(laser insitu keratomileusis,LASIK)前和术后眼压测量中的应用价值。方法在术前以及术后第1周和第4周,分别用GAT和DCT测量30例60眼的眼压,对所得结果采用SPSS 11.5统计分析软件进行统计学处理。结果中央角膜厚度(centralcorneal thickness,CCT)和GAT读数相关,而与DCT读数无关。术前眼压和术后第1周、第4周的眼压比较,GAT读数分别下降(5.00±1.12)mmHg和(5.45±1.13)mmHg,DCT则无显著性差异。结论LASIK导致的CCT变化可影响GAT测量结果的准确性,但对DCT无影响,因此,DCT更适用于正常眼以及曾接受LASIK手术眼的眼压测量。     

中央角膜厚度对压平眼压计测量值的影响

目的采用非接触式角膜内皮镜测量高眼压症与临床常见类型青光眼患者的中央角膜厚度central corneal thickness(CCT),并与正常人CCT平均值比较,探讨CCT对青光眼诊断、分类与治疗的指导意义.方法采用KONAN非接触式角膜内皮镜测量中央角膜厚度,Goldmann压平眼压计测量眼内压(IOP).将39例52眼原发性开角型青光眼(POAG),32例45眼慢性闭角型青光眼(CACG),18例29眼高眼压症眼(OHT),15例24眼正常眼压性青光眼(NTG),34例66眼可疑开角型青光眼(GS)的CCT和IOP值与173例322眼正常眼进行比较研究.所有资料输入计算机后在Windows操作环境下使用SPSS10.0统计软件进行统计分析.结果平均CCT值比较高眼压症(OHT)眼(600.21±24.20μm)＞POAG眼(574.37±31.92μm)＞正常对照眼(554.78±32.61μm)＞NTG眼(528.43±36.40μm).OHT、NTG、POAG眼与正常眼的CCT值有差异(F=9.629,P=0.000),CACG眼与POAG及正常眼CCT值均无差异(P=0.119).GS眼CCT值(564.72±31.96μm)较正常眼厚.CCT与IOP成直线正相关,眼压测量值的校正公式为眼压校正值(mmHg)=-(测得的角膜厚度μm-555μm)×(1/24).IOP经CCT校正后,OHT眼平均高估1.89mHg,NTG眼平均低估1.1mmHg,POAG眼平均高估0.80mmHg.根据经CCT校正后的IOP值,13.5%POAG眼重新诊断为NTG眼,34.5%OHT眼重新诊断为正常眼,16.7%NTG眼重新诊断为POAG眼.结论非接触式角膜内皮镜能准确地测量中央角膜厚度.OHT眼CCT较厚,而NTG眼CCT较薄.CCT测量对青光眼的分类与治疗有重要的指导意义,应作为OHT、NTG及GS的常规检查项目.     

Comparison of dynamic contour tonometry and Goldmann applanation tonometry following penetrating keratoplasty

Objective: To evaluate dynamic contour tonometry (DCT) versus Goldmann applanation tonometry (GAT) intraocular pressure (IOP) measurements in eyes that underwent penetrating keratoplasty (PKP).Design: Prospective, cross-sectional, observational study.Participants: Thirty-one eyes of 28 patients were examined after PKP.Methods: All eyes had undergone PKP with interrupted sutures. The postoperative period was more than 1 year for 25 eyes and less than 1 year for 6. Sutures were removed based on corneal topography and refraction. IOP was measured by both DCT and GAT methods and was correlated to the number of remaining sutures.Results: IOP readings were successfully obtained in 25/31 (80.6%) with DTC and in 21/31 (67.7%) with GAT (p = 0.25). In eyes with fewer than 4 remaining sutures, both methods were successful. In eyes with more than 4 sutures, the success rates of DCT and GAT were 66.7% and 44.4%, respectively (p = 0.18). In PKPs with a postoperative period of more than 1 year, the success rates of DCT and GAT were 96% and 84%, respectively (p = 0.16). In 20 eyes, both methods measured the IOP. The mean IOP obtained by DCT (16.6 [SD 2.8] mm Hg) was higher than the mean IOP obtained from GAT (15.1 [SD 3.6] mm Hg). The IOPs from the 2 instruments correlated significantly (p < 0.05) and the mean difference was 1.5 mm Hg.Conclusions: The success rate in measuring IOP with DCT and GAT did not show any statistically significant difference. Both methods were less effective measuring the IOP after recent PKPs and regrafts. However, DCT seemed to be superior to GAT in corneas with more than 4 remaining sutures and in PKPs performed more than 1 year earlier. The absolute values of IOP were higher with DCT than with GAT.     

Comparison of dynamic contour tonometry with Goldmann applanation tonometry in glaucoma practice

Purpose: To compare intraocular pressure (IOP) readings taken using dynamic contour tonometry (DCT) with IOP readings taken with Goldmann applanation tonometry (GAT) in eyes with glaucoma or ocular hypertension. Methods: The present study included 100 eyes in 100 patients with glaucoma or ocular hypertension. After pachymetry DCT and GAT were performed. Intraocular pressures as measured with DCT and GAT were compared with one another and with central corneal thickness (CCT). Results: Mean DCT IOP measurements (20.1 ± 4.3 mmHg) were significantly (p < 0.001) higher than GAT IOP values (17.9 ± 4.7 mmHg). The mean difference between DCT and GAT measurements was 2.1 mmHg (range ? 3.4 to 9.7 mmHg). The difference followed a normal distribution. Measurements made with DCT and GAT correlated significantly with one another (Spearman’s rho = 0.761, p < 0.001). Neither GAT nor DCT measurements showed a significant correlation with CCT (537 ± 39 μm, range 458–656 μm). Multivariate regression analysis has shown that the difference between DCT and GAT is influenced significantly by ocular pulse amplitude (r = ? 0.334, p = 0.001) and it is not influenced by CCT (r = ? 0.106, p = 0.292). Conclusions: In eyes with glaucoma or ocular hypertension, DCT facilitates suitable and reliable IOP measurements which are in good concordance with GAT readings. Variation in CCT cannot by itself explain the differences in measurements taken with DCT and GAT in a number of eyes.     

The effect of contact lens-induced corneal edema on Goldmann applanation tonometry and dynamic contour tonometry

Purpose  To evaluate the effect of contact lens-induced corneal edema on intraocular pressure (IOP) measurements using Goldmann applanation tonometry (GAT) and dynamic contour tonometry (DCT) in Asian subjects. Participants  The study included 40 eyes of 20 normal volunteers with no evidence of ocular disease. Methods  Forty eyes of 20 healthy volunteers were required to wear soft contact lenses for 2 hours to induce corneal swelling. Central corneal thickness (CCT) and IOP were measured before and immediately after contact lens wear using specular microscope, GAT, and DCT. The IOP measurements by GAT and DCT were compared. The changes in the CCT and the IOP measurements after wearing contact lenses were assessed. Results  The mean CCT of the 40 eyes evaluated was 532.6 ± 31.6 μm. The mean IOP was 11.78 ± 2.04 mmHg for the GAT and 14.46 ± 1.89 mmHg for the DCT, and the difference was statistically significant (P < 0.001). After wearing contact lenses, the mean CCT was 553.2 ± 34.3 μm, which was 20.6 ± 12.9 μm greater than before wearing them (P < 0.001). The mean IOP measurements of the GAT and DCT were decreased after wearing the contact lenses. The mean decrease of the GAT values was 0.43 ± 1.95 mmHg, which was not statistically significant (P = 0.175). However, the mean decrease of the DCT readings, which was 0.75 ± 1.74 mm Hg, was statistically significant (P = 0.010). Conclusion  The IOP measurements with DCT were significantly higher than those with GAT in healthy Asian eyes. Although the mean IOP measurements of both the GAT and the DCT were decreased in the edematous cornea, IOP measurements of the DCT were more affected by corneal edema than were the GAT. The authors have no proprietary, commercial, or financial interests in any of the products described in this study.     

Deviations between transpalpebral tonometry using TGDc-01 and Goldmann applanation tonometry depending on the IOP level

Background Recent comparisons between transpalpebral tonometry using TGDc-01 and Goldmann applanation tonometry were performed in populations with IOPs between 10 and 20 mmHg. The purpose of this study was to evaluate device deviations depending on different IOP levels (range 5–40 mmHg).Methods A total of 68 eyes of 68 patients were included and assigned to four IOP levels according to an initial applanation tonometry assessment: level I, <10 mmHg (n=8); level II, 10–19 mmHg (n=20); level III, 20–29 mmHg (n=20); and level IV, 30 mmHg (n=20). Two independent and randomized observers performed three replicate measurements per eye—observer 1 using TGDc-01 tonometry, and observer 2 using Goldmann applanation tonometry. Intraindividual deviations between measurement results were investigated concerning clinical relevance by medians and quartiles, concerning statistical significance by pairwise sign tests; p values <0.05 indicate local statistical significance.Results In patients with initial IOP 20 mmHg, TGDc-01–based tonometry significantly underestimated the IOP as based on Goldmann applanation tonometry (p<0.001). This effect increased with increasing IOP: IOP level III median difference (TGDc-01 – Goldmann) –1.3 mmHg (interquartile range, –2.5, –0.4), IOP level IV median difference –2.7 mmHg (–3.7, –1.0). In patients with initial IOP <10 mmHg, an at least gradual underestimation by TGDc-01 tonometry (p=0.219; median difference, –0.6, –1.6, 0) was observed. A total 18% of patients showed device deviations >±3 mmHg, and even 35% of those patients with initial IOP 30 mmHg.Conclusions TGDc-01–based tonometry demonstrated an increasing underestimation of IOP with increasing IOP levels when compared with the current standard method of Goldmann applanation tonometry.     

Comparison of Proview phosphene tonometry with Goldmann applanation tonometry

BACKGROUND: To compare intraocular pressures obtained using a handheld pressure phosphene tonometer (PPT) (Proview, Bausch & Lomb Pharmaceuticals, Inc., Tampa, Fla.) with Goldmann applanation tonometry. METHODS: Comparative case series of 30 randomly selected patients. RESULTS: The readings obtained with the pressure phosphene tonometer display a higher mean and a larger standard deviation than those obtained with the Goldmann applanation tonometer (GAT). Differences between PPT and GAT readings tended to decrease as a function of increased Goldmann levels. The relation of Proview and Goldmann readings (r = 0.32) and the scatterplot were not consistent with the hypothesis that the 2 methods are equivalent. INTERPRETATION: Our results indicate that the pressure phosphene-type handheld tonometry method, which does not appear to provide an accurate and consistent measure of intraocular pressure, is substantially less reliable than the Goldmann method.     

Dynamic contour tonometry versus Goldmann applanation tonometry: a comparative study

Background Various sources of error, including central corneal thickness (CCT) and structural corneal rigidity, have been proposed for Goldmann applanation tonometry (GAT). The Pascal dynamic contour tonometer (DCT) is a novel device designed for intraocular pressure (IOP) measurements assumed to be largely independent of CCT and corneal curvature. We compared DCT with GAT in eyes with normal corneas of various thickness.Methods We prospectively measured IOP using DCT and GAT in random order in 100 eyes of 100 subjects (M:F=46:54; mean age 42±19, range 23–88 years).Results Mean DCT values were about 1mmHg higher than GAT readings (16±3 vs 15±3 mmHg, p=0.001). Bland–Altman analysis of individual pairs of DCT and GAT measurements revealed a bias of –1.0 mmHg [95% confidence interval (CI): ±1.2]. Neither GAT nor DCT showed a significant correlation with CCT (533±48, range 399–641 m).Conclusions In eyes with normal corneas, DCT allows suitable and reliable IOP measurements which are in good concordance with GAT. Comparison of DCT with intracameral manometry is desirable in the future.     

Effects of topical anaesthetics and repeated tonometry on intraocular pressure

Purpose: To investigate the effects of repeated measurements of intraocular pressure (IOP) using Goldmann applanation tonometry (GAT) and applanation resonance tonometry (ART) to identify mechanisms contributing to the expected IOP reduction. Methods: A prospective, single‐centre study with six healthy volunteers. Consecutive repeated series (six measurements/serie/method) were made alternately on both eyes for 1 hr with oxybuprocaine/fluorescein in the right eye and tetracaine in the left. The left eye was Pentacam^® photographed before and repeatedly for 20 min after the IOP measurements. On a separate occasion, the same volunteers received the same amount of anaesthetic drops for 1 hr but without repeated IOP measurements. Results: A significant IOP reduction occurred with both ART and GAT in the oxybuprocaine‐treated eye, ?4.4 mmHg and ?3.8 mmHg, respectively and with ART in the tetracaine eye, ?2.1 mmHg. There was a significant difference in IOP reduction between the oxybuprocaine and tetracaine eyes with ART. There was a significant drop in anterior chamber volume (ACV) immediately after the IOP measurements, ?12.6 μl that returned to pretrial level after 2 min. After 1 hr of receiving anaesthetic eye drops (without IOP measurements), the IOP decreased significantly in the oxybuprocaine eye for both ART and GAT, ?3.1 and ?1.7 mmHg, respectively, but not in the tetracaine eye (p = 0.72). Conclusion: The IOP reduction cannot be explained solely by aqueous humor being pressed out of the anterior chamber. While significant IOP reduction occurred with both tetracaine and oxybuprocaine after repeated mechanical applanation, the IOP reduction was significantly greater with oxybuprocaine.     

Diaton tonometry: an assessment of validity and preference against Goldmann tonometry

Background: To assess agreement between the Diaton, a new transpalpebral tonometer, and Goldmann applanation tonometry, the accepted gold standard. Design: Comparative study of two devices in a hospital setting. Participants: Two hundred and fifty‐one patients attending the eye casualty and general ophthalmology clinics at St James' University Hospital, Leeds between February and December 2009. Methods: Intraocular pressure was measured using Goldmann applanation tonometry and Diaton tonometry by one examining ophthalmologist. Patient preference for either technique was also recorded. Main Outcome Measures: Intraocular pressure measured by Diaton was compared with intraocular pressure measured by Goldmann applanation tonometry. Limits of agreement were determined using the Bland‐Altman method. Results: Two hundred and fifty right eyes underwent both Goldmann applanation tonometry and Diaton tonometry. Mean intraocular pressure was 13.8 ± 3.6 mmHg using Goldmann applanation tonometry and 13.2 ± 4.3 mmHg using Diaton tonometry. Upper and lower limits of agreement were +8.4 mmHg and ?9.6 mmHg, respectively. Order of intraocular pressure measurement and positioning did not influence limits of agreement in a clinically significant manner. Overall, more patients expressed preference for Diaton tonometry (40.2%) than Goldmann applanation tonometry (30.3%). Those aged 50 or less were more likely to prefer Diaton tonometry. Conclusions: The Diaton tonometer is portable, lightweight, user‐friendly and well tolerated by patients. However, it shows poor agreement with Goldmann applanation tonometry, thereby precluding it from being regarded as a substitute in routine clinical practice.     

Comparison of Goldmann applanation tonometry, rebound tonometry and dynamic contour tonometry in normal and glaucomatous eyes

AIM: To compare the intraocular pressure (IOP) measurements obtained with the rebound tonometry (RT), dynamic contour tonometry (DCT) and Goldmann applanation tonometry (GAT) in normal and glaucomatous eyes and investigate the effects of central corneal thickness (CCT) and corneal curvature (CC) on IOP measurements. METHODS: One hundred and twenty-four eyes of 124 subjects were enrolled in this cross-sectional study. Fifty-six of participants were healthy individuals and 68 of them were glaucomatous patients. IOP was measured on each subject always in the same order, ICare RT-Pascal DCT-GAT, after a minimum interval of 10min between measurements. CCT and CC were measured using a rotating Scheimpflug camera before the IOP measurements in all subjects. One way repeated measures ANOVA, Pearson correlation coefficient and regression analysis, and Bland-Altman analysis was used for the statistical assessment. RESULTS: Mean IOP for all enrolled eyes was 16.00±3.80 mm Hg for GAT, 16.99±4.91 mm Hg for RT, and 20.40±4.44 mm Hg for DCT. Mean differences between GAT and RT was -1.75±3.41 mm Hg in normal (P<0.001) and -0.37±3.00 mm Hg in glaucomatous eyes (P=0.563). Mean differences between GAT and DCT was -4.06±3.42 mm Hg in normal (P<0.001) and -4.67±3.12 mm Hg in glaucomatous eyes (P<0.001). GAT and RT were significantly positive correlated with CCT in normal (r=0.317, P=0.017 and r=0.576, P<0.001, respectively) and glaucomatous eyes (r=0.290, P=0.016 and r=0.351, P=0.003, respectively). DCT was also significantly positive correlated with CCT in normal eyes (r=0.424, P=0.001) but not in glaucomatous eyes (r=0.170, P=0.165). All tonometers were unaffected by CC. CONCLUSION: IOP measurements by RT and DCT were significantly higher than GAT. DCT has highest IOP measurements among these tonometers. RT was most influenced tonometer from CCT although all tonometers were significantly positive correlated with CCT except DCT in glaucomatous eyes. CC did not influence IOP measurements.     

动态轮廓眼压计与Goldmann压平眼压计及非接触眼压计测量眼压的对比研究

目的探讨动态轮廓眼压计(DCT)与Goldmann压平眼压计(GAT)及非接触眼压计(NCT)测量眼压的准确性,并比较三种眼压计测量结果与中央角膜厚度(CCT)的相关性。设计前瞻性、比较性病例系列。研究对象连续选取90例(90眼)10~76岁正常人。方法采用KONAN非接触式角膜内皮镜测量CCT后,对所有入选者单眼以随机顺序采用Pascal型DCT、GAT及Topcon型NCT测量眼压。测量结果两两比较,并将眼压值与CCT进行直线回归分析。主要指标眼压值,Pearson相关系数。结果 90例正常人DCT眼压平均值(17.33±2.71 mm Hg)明显高于GAT(14.27±2.81 mm Hg)(P=0.000)及NCT(14.67±2.93 mm Hg)(P=0.000),平均差异分别为(3.06±2.01)mm Hg和(2.67±2.20)mm Hg;GAT与NCT之间平均差异为(-0.39±2.29)mm Hg(P=0.105)。DCT与GAT眼压值之间相关系数r=0.736(P=0.000);与NCT眼压值之间相关系数r=0.699(P=0.000)。GAT、NCT眼压值与CCT均明显相关(r=0.370,P=0.000;r=0.508,P=0.000);DCT眼压值与CCT无明显相关性(r=0.051,P=0.639)。DCT和GAT的差值与年龄无明显相关性(r=0.064,P=0.052)。结论 DCT测量的眼压值虽高于GAT及NCT,但不受CCT的影响,可能较GAT和NCT测量的眼压值更接近真实值。