Ex vivo evaluation of Tono-Pen and pneumotonometry in cat eyes

Josef Stoiber, Viviana Fernandez, Peggy D. Lamar, Wolfgang Hitzl, Francisco Fantes, Jean-Marie A Parel

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

Purpose: To evaluate the validity and intraobserver reliability of intraocular pressure (IOP) measurements with both pneumotonometry and the Tono-Pen in a closed ex vivo system in cat eyes. Methods: IOP was increased step by step in 5 enucleated cat eyes, while taking IOP measurements with the Tono-Pen and pneumotonometry. The outcomes were compared to readings of a digital manometer simultaneously measuring the actual pressure in the anterior chamber. Results: Pneumotonometry overestimated IOP below 15 mm Hg and underestimated pressures above 20 mm Hg. Tono-Pen tonometry considerably underestimated IOP over the whole spectrum in all of the eyes tested. The pneumotonometer was identified as the more valid and reliable instrument for cat eyes. Conclusion: Both tonometers are clinically useful tools to assess IOP for glaucoma studies using a cat animal model. However, one has to consider underestimation of IOP in the upper ranges. A correction formula can be used to calculate the actual IOP.

Original languageEnglish
Pages (from-to)13-18
Number of pages6
JournalOphthalmic Research
Volume38
Issue number1
DOIs
StatePublished - Dec 1 2005

Fingerprint

Intraocular Pressure
Cats
Pressure
Manometry
Anterior Chamber
Reproducibility of Results
Glaucoma
Reading
Animal Models

Keywords

  • Intraocular pressure measurements, accuracy
  • Pneumotonometry
  • Tono-Pen

ASJC Scopus subject areas

  • Ophthalmology

Cite this

Stoiber, J., Fernandez, V., Lamar, P. D., Hitzl, W., Fantes, F., & Parel, J-M. A. (2005). Ex vivo evaluation of Tono-Pen and pneumotonometry in cat eyes. Ophthalmic Research, 38(1), 13-18. https://doi.org/10.1159/000088492

Ex vivo evaluation of Tono-Pen and pneumotonometry in cat eyes. / Stoiber, Josef; Fernandez, Viviana; Lamar, Peggy D.; Hitzl, Wolfgang; Fantes, Francisco; Parel, Jean-Marie A.

In: Ophthalmic Research, Vol. 38, No. 1, 01.12.2005, p. 13-18.

Research output: Contribution to journalArticle

Stoiber, J, Fernandez, V, Lamar, PD, Hitzl, W, Fantes, F & Parel, J-MA 2005, 'Ex vivo evaluation of Tono-Pen and pneumotonometry in cat eyes', Ophthalmic Research, vol. 38, no. 1, pp. 13-18. https://doi.org/10.1159/000088492
Stoiber, Josef ; Fernandez, Viviana ; Lamar, Peggy D. ; Hitzl, Wolfgang ; Fantes, Francisco ; Parel, Jean-Marie A. / Ex vivo evaluation of Tono-Pen and pneumotonometry in cat eyes. In: Ophthalmic Research. 2005 ; Vol. 38, No. 1. pp. 13-18.
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