Uso do tonômetro de aplanação portátil Kowa HA-2 na mensuração da pressão intraocular em gatos

Abstract

The objective of this study was to measurement of the intraocular pressure (IOP) with Kowa HA-2 tonometer in cats analyzing the calibration, the accuracy and the validation of ambulatory clinical use. For calibration the post-mortem study was accomplished in 10 healthy eyes of 5 cats comparing the ocular manometry with the values of the IOP checked with the tonometer. For evaluation of the accuracy an in vivo study was accomplished in 20 healthy eyes of 10 anesthetized cats being compared the ocular manometry with the IOP obtained with the tonometer. For validation of the ambulatory clinical study of the IOP measurement was accomplished in 78 eyes of 39 healthy cats, in 7 eyes with clinical signs of glaucoma and in 20 eyes with clinical signs of uveitis. The correlation coefficient (r²) between the manometer and the tonometer was 0.993 and the equation of lineal regression was y=0.0915x+0.0878 in postmortem study. In the in vivo study the medium values of IOP in the manometry were 15.6±1.1 mmHg and in the tonometry were 15.5±1.2 mmHg, there was no statistics significant difference between the manometry and the tonometry. In the ambulatory clinical study with healthy cats the medium values of IOP with the tonometer were 15.0±1.5 mmHg, in the eyes with clinical signs of glaucoma were 38,4±8,1 mmHg and in the eyes with clinical signs of uveitis were of 10,4±2,0 mmHg. Therefore, there was a satisfactory correlation and accuracy between the IOP values obtained by direct ocular manometry and the tonometer in question. In the ambulatory clinical study the IOP values obtained with the tonometer were compatible for animals with healthy eyes and with clinical signs of glaucoma and uveitis. So, we can conclude that the Kowa HA-2 tonometer can be used in the routine ophthalmic examination, as it is a practical method for IOP measurement in cats.