A NEW MODEL OF TRANSIENT ISCHEMIA OF RABBIT EYES AND A QUANTITATIVE ASSESSMENT OF ISCHEMIA DEGREE USING OPHTHALMOPLETHYSMOGRAPHY

Purpose: to create a model of transient eye ischemia in order to study the effectiveness of drugs affecting the intensity of ocular blood flow in ischemic conditions, and to develop a method of quantifying the extent of ischemia. Material and methods. The study involved 72 Chinchilla rabbits. For the first time, the vasoconstrictive drug Phenylephrine 10 mg/ml was used to create an experimental model of ocular ischemia. The degree of ischemia was quantitatively assessed by the method of ophthalmoplethysmography, adapted for animals, while the degree of hypoxia was measured by enzymatic amperometric determination of lactate concentration in the intraocular fluid. Results. The effect of phenylephrine on the development of eye ischemia was found to be dose-dependent. After subconjunctival administration of phenylephrine, the maximum decrease in the minute volume of blood flow occurs in the interval from 60 min to 120 min. The time of permissible repeated injection of phenylephrine for the prolongation of ischemia development period was established at the 90th minute after the first injection, while the period of development of transient ischemia of the rabbit's eye is longer - 240 min. An increased content of lactate in the intraocular fluid after an injection of phenylephrine was noted, which points to the development of hypoxia due to transient ischemia of eye tissues. Conclusion. The proposed experimental model of transient rabbit ischemia developed by us may be used to study the efficiency of drugs affecting the intensity of ocular blood flow. It provides the possibility to control the dose of the ischemic factor and to avoid side effects. For citation: Chesnokova N.B., Grigoryev A.V., Mustafayeva K.N., Beznos O.V. A new model of transient ischemia of rabbit eyes and a quantitative assessment of ischemia degree using ophthalmoplethysmography. Russian ophthalmological journal. 2018; 11 (2): 35-40. doi: 10.21516/2072-0076-2018-11-2-35-40 (In Russian)