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Jayasuriya, A.C., Ghosh, S., Scheinbeim, J.I., Lubkin, V., Bennett, G. and Kramer, P.A. (2003) A Study of Piezoelectric and Mechanical Anisotropies of the Human Cornea. Biosensors and Bioelectronics, 18, 381-387.
http://dx.doi.org/10.1016/S0956-5663(02)00144-6

has been cited by the following article:

• TITLE: On the Validity of the Imbert-Fick Law: Mathematical Modelling of Eye Pressure Measurement

  AUTHORS: Gabriela González Castro, Alastair D. Fitt, John Sweeney

  KEYWORDS: Tonometry, Finite Element Analysis, Imbert-Fick Law

  JOURNAL NAME: World Journal of Mechanics, Vol.6 No.3, March 23, 2016

  ABSTRACT: Ophthalmologists rely on a device known as the Goldmann applanation tonometer to make intraocular pressure (IOP) measurements. It measures the force required to press a flat disc against the cornea to produce a flattened circular region of known area. The IOP is deduced from this force using the Imbert-Fick principle. However, there is scant analytical justification for this analysis. We present a mathematical model of tonometry to investigate the relationship between the pressure derived by tonometry and the IOP. An elementary equilibrium analysis suggests that there is no physical basis for traditional tonometric analysis. Tonometry is modelled using a hollow spherical shell of solid material enclosing an elastic liquid core, with the shell in tension and the core under pressure. The shell is pressed against a rigid flat plane. The solution is found using finite element analysis. The shell material is anisotropic. Values for its elastic constants are obtained from literature except where data are unavailable, when reasonable limits are explored. The results show that the force measured by the Goldmann tonometer depends on the elastic constant values. The relationship between the IOP and the tonometer readings is complex, showing potentially high levels of inaccuracy that depend on IOP.