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

Abstract

Objective-To examine the practical aspects, accuracy, and reproducibility of 2 new automatic handheld tonometers in dogs and compare them with results for 2 established applanation tonometers. Animals-15 freshly enucleated canine eyes for manometric evaluation and 20 conscious research dogs, 20 client-owned dogs, and 12 dogs with acute glaucoma for clinical tonometry.

Design of an intraocular pressure curve protocol for use in dogs

“…Solely from a corneal health perspective, and based on the findings of the present study, rebound tonometry seems more appropriate than applanation tonometry for the purpose of serial measurement of IOP for the purpose of plotting an IOPC. In addition, the authors of the present study also recommend the same tonometer is used throughout an IOPC and in subsequent IOPCs in the same patient, because rebound and applanation tonometers might result in different readings of the same eye (Görig et al 2006, Slack et al 2012). …”

In Vitro and In Vivo Comparison of Applanation Tonometry and Rebound Tonometry in Dogs

“…An added benefit is that topical anesthetics are not needed for detection of the animal's IOP [7,10,12]. There are reports dealing with the usefulness and/or accuracy of TV in animals and birds [1,6,7,[9][10][11][12]. In dogs, TP displayed lower IOP values than TV in in vitro enucleated eyes, although the relation between the two tonometries in glaucomatous eyes was not the same as in vitro [7].…”

“…Applanation tonometry, such as TONO-PEN XL (TP), is widely used in the field of veterinary ophthalmology, though it includes potential problems with inaccuracies caused by manual measurement and requires application of a topical anesthetic before IOP measurement [18]. On the other hand, rebound tonometry, such as TonoVet (TV), which has recently become available, is expected to be more reliable than TP, because a constant pressure can be given to the cornea by a mechanically launched probe, thereby providing increased accuracy of IOP measurements [7,10,12]. An added benefit is that topical anesthetics are not needed for detection of the animal's IOP [7,10,12].…”

“…There are reports dealing with the usefulness and/or accuracy of TV in animals and birds [1,6,7,[9][10][11][12]. In dogs, TP displayed lower IOP values than TV in in vitro enucleated eyes, although the relation between the two tonometries in glaucomatous eyes was not the same as in vitro [7]. Information about the relationship of IOP evaluated by TP and TV is essential for veterinary practitioners, since the number of veterinary ophthalmologists using both TP and TV has increased recently to assure accurate diagnoses of animals with ophthalmic diseases.…”

“…On the other hand, rebound tonometry, such as TonoVet (TV), which has recently become available, is expected to be more reliable than TP, because a constant pressure can be given to the cornea by a mechanically launched probe, thereby providing increased accuracy of IOP measurements [7,10,12]. An added benefit is that topical anesthetics are not needed for detection of the animal's IOP [7,10,12]. There are reports dealing with the usefulness and/or accuracy of TV in animals and birds [1,6,7,[9][10][11][12].…”