Individual-specific tonometry on porcine eyes

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

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Intraocular pressure (IOP) monitoring is important in the diagnosis and management of glaucoma. The measurement of IOP is affected by corneal properties, but the effect of corneal stiffness on IOP measurement is unaccounted for in pressure measurement instruments such as the Goldmann Applanation Tonometer (GAT). A new instrumented non-invasive indentation tonometry that can measure IOPIST, a corneal stiffness-corrected intraocular pressure is developed. The inter-individual corneal variations of 12 porcine eyes ex vivo were independently characterized; and their true intraocular pressure, IOPT's, were set using a manometer before indentation using the new indentation tonometry. Analyses of the load-displacement data showed that porcine corneal stiffness varied more than five times from 0.045 to 0.253. N/mm. Analysis showed that, without individual stiffness correction, inter-individual variation of IOPGAT can vary up to 8. mm. Hg from IOPT at 15. mm. Hg; the error becomes larger at high IOPT. In comparison when corneal stiffness is accounted for, IOPIST has a significantly smaller error of 1.82 ± 1.70. mm. Hg for IOPT between 12 and 40. mm. Hg than IOPGAT. The results showed that the new tonometry successfully accounted for inter-individual variations in IOP measurement.

Original languageEnglish
Pages (from-to)96-101
Number of pages6
JournalMedical Engineering and Physics
Volume36
Issue number1
DOIs
Publication statusPublished - Jan 2014
Externally publishedYes

Fingerprint

Manometry
Intraocular Pressure
Swine
Stiffness
Pressure measurement
Indentation
Manometers
Loads (forces)
Glaucoma
Monitoring
Pressure

Keywords

  • Biomechanics
  • Cornea
  • Glaucoma
  • Intraocular pressure
  • Stiffness
  • Tonometry

ASJC Scopus subject areas

  • Biomedical Engineering
  • Biophysics

Cite this

Individual-specific tonometry on porcine eyes. / Leung, Leo K K; Ko, Match W L; Lam, David C C.

In: Medical Engineering and Physics, Vol. 36, No. 1, 01.2014, p. 96-101.

Research output: Contribution to journalArticle

Leung, Leo K K ; Ko, Match W L ; Lam, David C C. / Individual-specific tonometry on porcine eyes. In: Medical Engineering and Physics. 2014 ; Vol. 36, No. 1. pp. 96-101.
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