Jóhannesson Gauti, Hallberg Per, Eklund Anders, Lindén Christina
Department of Clinical Sciences, Ophthalmology, Umeå University, Sweden.
Acta Ophthalmol. 2008 Sep;86(6):614-21. doi: 10.1111/j.1600-0420.2007.01112.x.
To compare intraocular pressure (IOP) measurements by Pascal, ICare and Goldmann applanation tonometry (GAT), to evaluate the effects of central corneal thickness (CCT) and curvature on IOP measurement and to estimate the intra-observer variability.
A prospective, single-centre study of 150 eyes with a wide range of pressures. Six masked IOP measurements/method; corneal thickness and curvature were studied for each eye. GAT was the reference.
IOPPascal and IOPICare correlated with IOPGAT (r = 0.91, 0.89). Mean ICare measurement exceeded GAT by 2 mmHg. Pascal measured higher than GAT at low IOPs and lower at high IOPs. For every 10 mmHg increase in IOP above 31 mmHg, Pascal measured 2 mmHg lower than GAT and vice versa. CCT was correlated significantly with IOPGAT (r = 0.23) and IOPICare (r = 0.43) but not with IOPPascal (P = 0.12). CCT was correlated with age. In a subgroup (>50 years), ICare and the difference between IOPGAT and IOPPascal were affected significantly by the CCT, whereas IOPGAT and IOPPascal were not. Corneal curvature was correlated significantly with IOPGAT (r = -0.27) and IOPPascal (r = -0.26) but not with IOPICare (P = 0.60). Intra-observer variability within each set of six measurements was approximately 2 mmHg, irrespective of method.
This study showed a reasonable overall correlation and concordance between the IOP obtained with the three instruments. None of the methods were completely independent of the biomechanical properties of the cornea. ICare showed a significant dependency upon CCT, whereas GAT and Pascal showed a significant dependency on corneal curvature. All methods showed intra-observer variability, which leaves room for further improvement of methods.
比较帕斯卡眼压计、ICare眼压计和戈德曼压平眼压计（GAT）测量眼压（IOP）的结果，评估中央角膜厚度（CCT）和曲率对眼压测量的影响，并估计观察者内变异性。
对150只眼压范围广泛的眼睛进行一项前瞻性单中心研究。每种方法进行6次盲法眼压测量；研究每只眼睛的角膜厚度和曲率。以GAT为参考标准。
帕斯卡眼压计测量的眼压（IOPPascal）和ICare眼压计测量的眼压（IOPICare）与GAT测量的眼压（IOPGAT）相关（r = 0.91，0.89）。ICare测量的平均眼压比GAT高2 mmHg。在低眼压时，帕斯卡眼压计测量值高于GAT，在高眼压时则低于GAT。眼压高于31 mmHg时，每升高10 mmHg，帕斯卡眼压计测量值比GAT低2 mmHg，反之亦然。CCT与IOPGAT（r = 0.23）和IOPICare（r = 0.43）显著相关，但与IOPPascal不相关（P = 0.12）。CCT与年龄相关。在一个亚组（年龄>50岁）中，CCT对ICare以及IOPGAT和IOPPascal之间的差异有显著影响，而IOPGAT和IOPPascal不受影响。角膜曲率与IOPGAT（r = -0.27）和IOPPascal（r = -0.26）显著相关，但与IOPICare不相关（P = 0.60）。每组6次测量中观察者内变异性约为2 mmHg，与测量方法无关。
本研究表明三种仪器测得的眼压之间总体具有合理的相关性和一致性。没有一种方法完全独立于角膜的生物力学特性。ICare显示出对CCT有显著依赖性，而GAT和帕斯卡眼压计显示出对角膜曲率有显著依赖性。所有方法均显示出观察者内变异性，这为进一步改进测量方法留下了空间。
