Tear function, corneal sensitivity and blinking frequency measurement in brachycephalic dogs

Abstract

Brachycephalic breeds constitute a significant percentage of ophthalmic care. The anatomical peculiarities associated to the eye, orbit, and ocular annexes these animals predispose to the occurrence of changes in the ocular surface (OS), and other ophthalmic disorders. Among the abnormalities involved directly or indirectly with the OS feature dry eye disease and ulcerative keratitis. In addition to anatomical conformation, other factors such as quantity and composition of the tear film and corneal sensitivity contribute to the high incidence of changes in OS, in these patients, which motivate the study delineation. With the aim of standardizing parameters for these factors, conceived to measure the frequency of blinking, aqueous tear production, the tear breakup time, and corneal sensitivity in brachycephalic breeds of dogs free of changes of the eye and its annexes. The frequency of blinking is quantified by counting the eyelid movements recorded images in the form of video. The tear production is measured by the Schirmer tear test. The tear breakup time is evaluated after the instillation of 1% fluorescein. The sensitivity of the cornea will be evaluated with the Cochet-Bonnet esthesiometer. Will be included in the survey, 15 brachycephalic dogs and 15 mesaticephalic also devoid of any eye disease, which constitutes a group to compare the parameters. The collected data are subjected to statistical evaluation in order to establish the mean values for each parameter and determine the occurrence of correlation therebetween. Be investigated, too, the occurrence of differences between the results obtained in brachycephalics and mesaticephalic dogs. (AU)