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Comparison of TonoLab, TonoVet Plus, and Tono-Pen AVIA Vet Tonometers for Measuring Intraocular Pressure in Rats
Tarcísio Guerra Guimarães1,2,3, Antônio Felipe P F Wouk4, Karla Menezes Cardoso1,2,3
1Faculty of Medicine, University of Coimbra, Coimbra Institute for Clinical and Biomedical Research (iCBR), area of Environment Genetics and Oncobiology (CIMAGO) and Institute of Biophysics, Faculty of Medicine, Coimbra, Portugal.
This study found weak agreement between TonoLab and TonoVet Plus, and negligible agreement between TonoLab and Tono-Pen AVIA Vet for measuring intraocular pressure (IOP) in rats. Understanding these device differences is crucial for accurate IOP interpretation in rodent research.
Area of Science:
- Veterinary Ophthalmology
- Animal Research Methods
Background:
- Accurate intraocular pressure (IOP) measurement is vital in rodent models for ocular research.
- Various animal-adapted tonometers exist, but their comparative agreement in rats is not well-established.
Purpose of the Study:
- To assess the agreement between IOP measurements obtained using TonoLab, TonoVet Plus, and Tono-Pen AVIA Vet tonometers in rats.
- To evaluate the relationship among these different tonometer devices.
Main Methods:
- Intraocular pressure (IOP) was measured sequentially in 24 rat eyes using TonoLab, TonoVet Plus, and Tono-Pen AVIA Vet.
- Agreement was analyzed using intraclass correlation coefficient (ICC) and Bland-Altman plots.
- Linear regression evaluated the relationship between TonoLab and the other two devices.
Main Results:
- Weak and non-significant agreement was found between TonoLab and TonoVet Plus (ICC = 0.173).
- Negligible and non-significant agreement was observed between TonoLab and Tono-Pen AVIA Vet (ICC = 0.011).
- Linear regression showed no significant relationship between TonoLab and either TonoVet Plus or Tono-Pen AVIA Vet.
Conclusions:
- The Tono-Pen AVIA Vet consistently yielded higher IOP values than TonoVet Plus, which in turn yielded higher values than TonoLab.
- Significant discrepancies exist between these tonometers, impacting the reliability of comparative IOP data in rats.
- Establishing tonometer-specific normal IOP values and understanding inter-device differences are essential for accurate interpretation in rodent ophthalmology.
