Validation of the Icare® TONOVET plus rebound tonometer in normal rabbit eyes

doi:10.1016/j.exer.2019.107698

Experimental Eye Research

Volume 185, August 2019, 107698

https://doi.org/10.1016/j.exer.2019.107698 Get rights and content

Abstract

To determine the accuracy and precision of the Icare^® TONOVET Plus rebound tonometer for measuring intraocular pressure (IOP) in normal rabbit eyes, as well as compare it to three other commercially available tonometers: the Icare^® TONOVET (TV01), Tono-Pen Vet™, and Tono-Pen AVIA Vet™. The anterior chambers of both eyes of three New Zealand White rabbits were cannulated, post-mortem. IOP was measured using each of the above four tonometers at manometric pressures ranging between 5 mmHg and 70 mmHg. Data were analyzed by linear regression, ANOVA, and Bland-Altman plots. A p-value of ≤0.05 was considered significant for all statistical tests. IOP values obtained with the TONOVET Plus (in ‘lapine’ mode) were significantly closer to manometric IOP than those obtained with the other tonometers tested. The TV01 (in ‘d’ dog setting) and Tono-Pen AVIA Vet™ were significantly more accurate compared to the Tono-Pen Vet™. All tonometers had high levels of precision, though the TONOVET Plus and TV01 were significantly more precise compared to the Tono-Pen AVIA Vet™. All tonometers tended to underestimate IOP, particularly at high pressures, however the TONOVET Plus was highly correlated with manometric IOP in the clinically relevant range of 5–50 mmHg. The TONOVET Plus is an appropriate choice of instrument for measuring IOP in rabbit eyes in both research and clinical settings.

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Acknowledgements

The authors would like to thank ICare Finland Oy for providing the TONVET Plus tonometer used in this study.

This work was supported in part by the National Institutes of Health [National Eye Institute grant number P30 EY16665] and unrestricted funds to the Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison from Research to Prevent Blindness.

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Citation Excerpt :
Besides, peripapillary RNFL thickness is automatically acquired and recorded by the software, while the macular retinal thickness and CCT are measured manually by two researchers independently. CRITICAL: The IOP values measured by different tonometers are usually consistent when the IOP is in the normal range, but there are certain deviations when the IOP is too high or too low (Gloe et al., 2019; McAllister et al., 2018; Tu et al., 2019b). Besides, the measured IOP can increase when animals are alert or struggling (anesthesia has not fully taken effect).
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¹: Contributed equally to this work.

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Validation of the Icare® TONOVET plus rebound tonometer in normal rabbit eyes

Abstract

Section snippets

Acknowledgements

Surv. Ophthalmol.

Ophthalmol. Times

Exp. Eye Res.

Ophthalmol. Times

Exp. Eye Res.

BioMed Res. Int.

Comparison of the use of new handheld tonometers and established applanation tonometers in dogs

Am. J. Vet. Res.

Comparison of rebound tonometry with Goldmann applanation tonometry and correlation with central corneal thickness

Br. J. Ophthalmol.

Correlations between corneal biomechanical properties measured with the ocular response analyzer and ICare rebound tonometry

J. Glaucoma

Validation of the Icare^® TONOVET plus rebound tonometer in normal rabbit eyes