Measurement of Intraocular Pressure in a Porcine Ex Vivo Model Eye

Abstract

Aims: To compare the pressure inside and outside the pig eye in relation to the location of cannulation for the injection of liquid into the anterior or vitreous chamber. Method: Eleven enucleated pig eyes were used. 46 measurements of intraocular pressure IOP were taken with a Perkins tonometer when the eye was cannulated in the anterior chamber. 49 measurements were taken when the eye was cannulated in the vitreous chamber. The eyeball was connected to a low -pressure transducer to control, maintain and modify the pressure in the eyeball. Results: No significant difference ( P=0.138) was found between the Perkins pressure measurements from cannulations in the anterior and vitreous chambers. A linear relationship between transducer and Perkins measurements was found when the eye was cannulated in the anterior chamber (IOP= -7.749+0.763 transducer;R2=0.940, p<0.001) and when it was cannulated in the vitreous chamber (IOP= -7.476+0.730 transducer, R2=0.885, p<0.001). No difference was found between the Perkins/transducer pressure ratios ( P=0.500 ANOVA) from cannulations in anterior and vitreous chambers. There were no differences in the measurements among eyes that could affect pressure outcomes. A direct relationship between the insufflate pressure inside the eyeball and the Perkins OriginalResearch Article