Bulletin "Veterinary biotechnology"

Veterynarna biotehnologija – Veterinary biotechnology, 2016, 28, 188-197 [in Ukrainian].

MEZHENSKYI A.A., e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

State Research Institute of Laboratory Diagnostics and Veterinary and Sanitary Expertise

Intraocular pressure in clinically healthy Horses and horses with uveitis

Introduction. Development of new and improvement of existing means and methods of measurement of intraocular pressure (IOP) in animals are the current trends of modern veterinary ophthalmology.

The goal of the work – to carry out verification of applanation tonometry method with using a veterinary tonometer Tonovet (Tiolat, Finland) in horses and to explore the IOP in clinically healthy horses and horses with uveitis.

Materials and methods of research. Studies carried out on clinically healthy horses (control group, n = 10) and horses with acute uveitis (n = 29) – the firstgroup, subacute uveitis (n = 17) – the second group and chronic uveitis (n = 41) – the third group.

Carrying out ophthalmic examination we measured IOP in both eyes of each horse with tonometer Tonovet. In all cases we performed blockade of eyelid-aural nerves and local surface anesthesia. We performed sedation to aggressive horses. The diagnosis uveitis we put comprehensively taking into account medical history, the results of the overall clinical and ophthalmological examinations, and laboratory tests.

Results of research and discussion.Measuring IOP in clinically healthy horses with tonometer Tonovet: OS was 23.9±4.7 mmHg and OD was 21.3±4.5 mmHg. In horses with acute uveitis founded IOP reduction from 7.1 and 6.1 mmHg to 16.8±1.4 and 15.2±1.2 mmHg, and in horses with chronic uveitis from 8.6 and 7.3 mmHg to 15.3±2.9 and 14.1±1.8 mmHg in the left and right eyes, respectively, in compare to the IOP of clinically healthy horses.

In horses with subacute uveitis founded nonsignificant decrease in IOP of 4.1 and 3 mmHg to 19.8±2.14 and 18.3±2.4 mmHg in the left and right eyes, respectively, compared with IOP in the control group of horses.

The most significant IOP reduction compared to clinically healthy horses was found in eyes of horses with chronic uveitis.

Conclusions and prospects for further research. IOP value in clinically healthy horses in measuring with tonometer Tonovet correspond to the reference value obtained with using other blood pressure monitors. In horses with acute and chronic uveitis, even with minor clinical changes, IOP significantly reduced in the affected eye, which allows recommending tonometry as informative and objective method of diagnosis of uveitis in horses.

Keywords: horses, eye disease, uveitis, intraocular pressure, tonometry.


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