Blanche D Rodrigues1,2, Fabiano Montiani-Ferreira1, Mariza Bortolini1, André T Somma1,2, András M Komáromy3, Peterson Triches Dornbusch1. 1. Graduate School of Veterinary Sciences, Department of Veterinary Medicine, Federal University of Paraná, Curitiba, Brazil. 2. Integrated Center of Veterinary Specialties (CIEV), Curitiba, Brazil. 3. Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI, USA.
Abstract
PURPOSE: To demonstrate the effect of different probe-cornea distances during intraocular pressure (IOP) data acquisition in dogs and rats. ANIMALS STUDIED: Twenty-four conscious dogs and 15 anesthetized Wistar rats. METHODS: Three interchangeable three-dimensional printed polylactide plastic spacer collars were used in place of the original Icare TonoVet® collar piece, which provided different distances (4, 6, and 8 mm) between the instrument's probe and the corneal surface. IOP values were obtained in sequence by a single observer, with the tonometer probe at a 4-, 6-, and 8-mm distance from the corneal surface. The dogs were gently restrained, and the rats were anesthetized with isoflurane. RESULTS: Intraocular pressure values obtained at 4, 6, and 8 mm from the TonoVet® probe to corneal surface distance in both dogs and rats were significantly different (P < .01). There was a small positive correlation between IOP (mm Hg) and probe-cornea distance (mm) (rs = 0.39 for dogs and rs = 0.51 for rats). In dogs, the mean IOP (± SD mm Hg) obtained at different distances were 16.2 ± 3.0 at 4 mm; 17.6 ± 3.4 at 6 mm; and 19.8 ± 3.8 at 8 mm. In rats, IOP values were 8.2 ± 1.5 at 4-mm; 9.4 ± 1.8 at 6-mm; and 10.5 ± 1.5 mm Hg at 8-mm distance. CONCLUSIONS: Probe-cornea distance of the Icare TonoVet® significantly affects IOP readings, even within the 4- to 8-mm range recommended by the manufacturer.
PURPOSE: To demonstrate the effect of different probe-cornea distances during intraocular pressure (IOP) data acquisition in dogs and rats. ANIMALS STUDIED: Twenty-four conscious dogs and 15 anesthetized Wistar rats. METHODS: Three interchangeable three-dimensional printed polylactide plastic spacer collars were used in place of the original Icare TonoVet® collar piece, which provided different distances (4, 6, and 8 mm) between the instrument's probe and the corneal surface. IOP values were obtained in sequence by a single observer, with the tonometer probe at a 4-, 6-, and 8-mm distance from the corneal surface. The dogs were gently restrained, and the rats were anesthetized with isoflurane. RESULTS: Intraocular pressure values obtained at 4, 6, and 8 mm from the TonoVet® probe to corneal surface distance in both dogs and rats were significantly different (P < .01). There was a small positive correlation between IOP (mm Hg) and probe-cornea distance (mm) (rs = 0.39 for dogs and rs = 0.51 for rats). In dogs, the mean IOP (± SD mm Hg) obtained at different distances were 16.2 ± 3.0 at 4 mm; 17.6 ± 3.4 at 6 mm; and 19.8 ± 3.8 at 8 mm. In rats, IOP values were 8.2 ± 1.5 at 4-mm; 9.4 ± 1.8 at 6-mm; and 10.5 ± 1.5 mm Hg at 8-mm distance. CONCLUSIONS: Probe-cornea distance of the Icare TonoVet® significantly affects IOP readings, even within the 4- to 8-mm range recommended by the manufacturer.
Authors: Diogo S Zanoni; Germana A Da Silva; Raaya Ezra-Elia; Márcio Carvalho; Juliany G Quitzan; Ron Ofri; José L Laus; Renee Laufer-Amorim Journal: Int J Exp Pathol Date: 2017-06 Impact factor: 1.925
Authors: André Tavares-Somma; Nathália Seabra; Bret A Moore; Mario Sato; Rogério R Lange; Fabiano Montiani-Ferreira Journal: J Zoo Wildl Med Date: 2017-12 Impact factor: 0.776