ASPECTS OF TONOMETRY OF THE EQUINE EYES W ITH THE TONO-PEN(R) XL

In 621 eyes, divided into five groups according to ophthalmological fi ndings, the intraocular pressure (IOP) was measured and the influence of age, breed, sex, ''excitement'' and state of clinical disorders of the eye on the IOP was calculated as mean value for each group. The in traocular pressure in horses with sound eyes (n = 334) ranged between 11 and 36 mm Hg with a mean value of 23,8 mm of Hg. In eyes affected w ith equine recurrent uveitis (ERU; n=69) the IOP (16,3 mm of Hg) was h ighly significant lower than in other groups (p < 0,001). Induced ''ex citement'' caused a significantly higher IOP (25,8 mm of Hg; p < 0,05) . The accuracy of the Tono-Pen(x) XL was investigated in comparison wi th ophthal-momanometry in enucleated eyes. With the help of the calcul ated regression formula (actuel IOP = [Tono-Pen(x) XL value + 5.16 mm of Hg]/0.84) a conversion table was set up to correct the results rece ived with the Tono-Pen(x) XL into the real IOP.