MORPHOLOGICAL CHANGES IN CHORIORETINAL COMPLEX OF RABBIT IMMEDIATELY AFTER EXPOSURE OF HIGH FREQUENCY ELECTRIC CURRENT (MODIFIED GENERATOR EC-300M1) COMPARED WITH DIODE LAZER COAGULATION

Introduction. Harmful effects minimizing of some factors, including laser, electric current on the eye tissues during various interventions is relevant area of ophthalmology. High frequency electric welding of biological tissues (HEWBT) can be considered as an alternative method of retinopexy with an ability to minimize the destructive effects of electric current on the retina and choroid.

Purpose. To investigate the chorioretinal complex morphological changes in rabbit immediately after high-frequency electric current exposure (modified generator EC-300M1).

Materials and methods. 7 rabbits (14 eyes) were in experimental studies. Group I: animals applied for welding applications on the retina using technology HEWBT with parameters: voltage — 14–16 V, current — 0.1 A, exposure 1–2 s, frequency 66 kHz). Group II: welding applications with a voltage of 18–20 V. Group III — chorioretinal burn formed using threshold diode endolazer coagulation. In the control group, no intervention was performed. Animal’s eyes were subjected by histological examination.

Results and discussion. Methods used physical effects on the retina differred in their severity caused by destructive changes. The most pronounced characteristic of the destructive action has threshold diode endolazer coagulation, which was accompanied by coagulation changes of all layers of the retina and choroid reactive changes. Less destructive effect was observed after HEWBT with parameters of electric current: voltage — 18–20 V. It was set significant expansion and bundle of ganglion cell layer and inner plexiform layer, due to the retina swelling and changes of intercellular substance. Moderate coagulation changes were observed in inner and outer nuclear layers. There was destruction of the rods and cones layer. There were changes as vasodilatation and blood stasis in the choroid. The most sparing effect of electric current was with voltage parameters 14–16 V. This effect was accompanied by swelling inner plexiform and ganglion cells layers of retina and moderate discomplexation in rods and cones layer. The changes in inner and outer nuclear layers were minimal and manifest by minimal сytoarchitectonics violations, which can be explained by layers swelling. Reactions on the part of choroid was not observed.

Conclusion. As a result of the pilot experimental study carried out on 7 rabbits (14 eyes), it was found that the most pronounced destructive effect on the retina and choroid has a threshold diode endolazer coagulation. Less destructive action has a HEWBT with a voltage of 18–20 V, аnd most sparing effect has a HEWBT with a voltage of 14–16 V.