Asejczyk-Widlicka Magdalena, Srodka Wieslaw
Department of Optics & Photonics, Faculty of Fundamental Problems of Technology, Wroclaw University of Science and Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw, Poland.
Deformable Body Mechanics Faculty Unit, Wrocław University of Science and Technology, Smoluchowskiego 25, 50-372 Wroclaw, Poland.
Clin Biomech (Bristol). 2020 Jan;71:24-28. doi: 10.1016/j.clinbiomech.2019.09.007. Epub 2019 Oct 5.
The problem of accuracy of intraocular pressure (IOP) measurement using Goldmann Applanation Tonometry (GAT) after a refractive surgery is still unresolved. In this study a numerical simulation of refractive surgery and GAT is proposed as a method to evaluate accuracy of the correction formula for GAT reading after changes in corneal curvature and thickness.
In the finite element analysis the effect of the corneal shell buckling was taken into account. This effect is responsible for the nonlinear relation of Goldmann applanation tonometer measurement and intraocular pressure. Goldmann applanation tonometry was simulated for different ablation depths and values of intraocular pressure levels.
The results of the simulation indicate a strong relation between the Goldmann applanation reading and the intraocular pressure level for values greater than nominal (about 16 mmHg). The estimation error of the intraocular pressure after changes in corneal geometry, is lower than 1 mmHg for IOP = 32 mmHg and lower than 3 mmHg for IOP = 48 mmHg.
The proposed correction formula of Goldmann applanation tonometry occurred to be useful in the cases after the corneal refractive surgery regardless of the intraocular pressure values and ablation depth.
屈光手术后使用Goldmann压平眼压计（GAT）测量眼压的准确性问题仍未解决。在本研究中，提出了屈光手术和GAT的数值模拟方法，以评估角膜曲率和厚度变化后GAT读数校正公式的准确性。
在有限元分析中考虑了角膜壳屈曲的影响。这种影响导致了Goldmann压平眼压计测量值与眼压之间的非线性关系。针对不同的消融深度和眼压水平值模拟了Goldmann压平眼压计。
模拟结果表明，对于大于标称值（约16 mmHg）的值，Goldmann压平眼压计读数与眼压水平之间存在很强的相关性。角膜几何形状改变后的眼压估计误差，对于眼压=32 mmHg时低于1 mmHg，对于眼压=48 mmHg时低于3 mmHg。
无论眼压值和消融深度如何，所提出的Goldmann压平眼压计校正公式在角膜屈光手术后的情况下都很有用。
