Characterization of corneal tangent modulus in vivo

Match W L Ko, Leo K K Leung, David C C Lam, Christopher K S Leung

Research output: Contribution to journalArticle

26 Citations (Scopus)

Abstract

Purpose: Intraocular pressure (IOP) measured using Goldmann Applanation Tonometry (GAT) changes with individual's corneal properties, but the method to measure the in vivo corneal material properties to account for individual variation in GAT IOP is not available. In this study, a new method to measure the IOP-dependent corneal tangent modulus in vivo is developed to address this research gap. Methods: Instrumented indentation and analysis were developed to measure the corneal tangent modulus. The validity of the method and procedure was verified using model silicone eye pressurized to different IOP. In addition, 15 porcine eyes and 3 rabbit eyes were tested using the corneal indentation at different set intraocular pressure and different indentation rates. Results: The results from silicone eye showed that the measured tangent modulus is in good agreement with the standard silicone rubber modulus. The results on the porcine eyes and rabbit eyes showed that the method can be used to measure corneal tangent modulus in vivo in the human range of intraocular pressure from 10 to 40 mmHg. Conclusions: An indentation method to measure the corneal tangent modulus in vivo was developed, and the IOP dependence of the corneal tangent modulus was characterized. The developed indentation method provides a new means to measure the in vivo corneal tangent modulus to account for individual and pressure variations in measurement of intraocular pressure.

Original languageEnglish
JournalActa Ophthalmologica
Volume91
Issue number4
DOIs
Publication statusPublished - Jun 2013
Externally publishedYes

Fingerprint

Intraocular Pressure
Manometry
Silicones
Swine
Rabbits
Silicone Elastomers
Pressure
Research

Keywords

  • corneal biomechanical properties
  • glaucoma
  • indentation instrumentation
  • stiffness
  • tangent elastic modulus

ASJC Scopus subject areas

  • Ophthalmology

Cite this

Ko, M. W. L., Leung, L. K. K., Lam, D. C. C., & Leung, C. K. S. (2013). Characterization of corneal tangent modulus in vivo. Acta Ophthalmologica, 91(4). https://doi.org/10.1111/aos.12066

Characterization of corneal tangent modulus in vivo. / Ko, Match W L; Leung, Leo K K; Lam, David C C; Leung, Christopher K S.

In: Acta Ophthalmologica, Vol. 91, No. 4, 06.2013.

Research output: Contribution to journalArticle

Ko, MWL, Leung, LKK, Lam, DCC & Leung, CKS 2013, 'Characterization of corneal tangent modulus in vivo', Acta Ophthalmologica, vol. 91, no. 4. https://doi.org/10.1111/aos.12066
Ko, Match W L ; Leung, Leo K K ; Lam, David C C ; Leung, Christopher K S. / Characterization of corneal tangent modulus in vivo. In: Acta Ophthalmologica. 2013 ; Vol. 91, No. 4.
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