title: Validation of rebound tonometry for intraocular pressure measurement in the rabbit.
abstract: Rabbits play a growing role in research into glaucoma surgical models and ocular drug delivery models. However, the lack of an accurate method for measuring intraocular pressure (IOP) in this animal has been a significant deficit. In this study we validated the use of the TonoVet rebound tonometer and provide conversion tables for its use in rabbits. Experiments were performed on 18 adult New Zealand White rabbits. The TonoVet measurements were obtained and compared to manometric readings by anterior chamber (AC) cannulation. The TonoVet position and 'd' (dog or cat) and 'p' (other species) modes were compared. The sensitivity of the TonoVet tonometer in assessing IOP changes was also tested. There was a strong linear correlation for both the 'd' mode (mean slope = 0.84 ± 0.03, r(2) = 0.99 ± 0.03) and the 'p' mode (mean slope = 0.64 ± 0.02, r2 = 0.97 ± 0.01) of the TonoVet with manometric IOP. However, the TonoVet had a tendency to underestimate IOP compared to manometry and conversion formulae were possible to calculate for both modes. The orientation of the TonoVet handle had no effect on IOP reading, as long as the groove was horizontal. No significant differences were observed when comparing right and left eyes (P > 0.05). IOP recovered four days after cannulation. Younger rabbits had lower IOP compared with older rabbits (P < 0.01). Timolol produced a 2.5 mmHg reduction in IOP 2 h later as detected by the TonoVet. Using the conversion table presented, the TonoVet is a reliable and precise tool for the measurement of IOP in rabbits.
authors.affiliation: Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne, VIC 3002, Australia; Eye Hospital, Harbin Medical University, No. 157 Baojian Road, Nangang District, Harbin, Heilongjiang Province 150001, China. Electronic address: hong.zhang@unimelb.edu.au.
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne, VIC 3002, Australia.
authors.forename: Dong
authors.initials: D
authors.lastname: Yang
authors.affiliation: Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne, VIC 3002, Australia.
authors.forename: Craig M
authors.initials: CM
authors.lastname: Ross
authors.affiliation: Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne, VIC 3002, Australia.
authors.forename: Jonathan P
authors.initials: JP
authors.lastname: Wigg
authors.affiliation: Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne, VIC 3002, Australia; Postgraduate Institute of Medical Education & Research, Sector 24-A, Chandigarh 160012, India.
authors.forename: Surinder
authors.initials: S
authors.lastname: Pandav
authors.affiliation: Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, 32 Gisborne Street, East Melbourne, VIC 3002, Australia.
authors.forename: Jonathan G
authors.initials: JG
authors.lastname: Crowston
mesh_terms: D000818:Animals; D000867:Anterior Chamber / Q000502:physiology; D002138:Calibration; D002404:Catheterization; D005260:Female; D007429:Intraocular Pressure / Q000502:physiology*; D011817:Rabbits; D015203:Reproducibility of Results; D014065:Tonometry, Ocular / Q000295:instrumentation*
keywords: glaucoma; intraocular pressure; non-invasive; rabbits; tonometer