Morphological changes of eye tissues after the influence of high‐frequency electric current welding with suprachoroidal approach to induce chorio‐retinal adhesion

Abstract

Purpose: to evaluate the morphological changes in eye tissue after the influence of high‐frequency electric current welding (HFECW) with suprachoroidal approach in rabbit's eyes in order to induce chorio‐retinal adhesion as an alternative treatment for retinal tears. Methods: 54 adult rabbits were used. The study complied to the ARVO statement for use of animals in ophthalmic and visual research. In the treated group, the retina was coagulated 7–10 mm from the limbus through a U‐shaped scleral incision with suprachoroidal approach using 23‐gauge tip and modified HFECW generator EK‐300 M1 (E.O. Paton Electric Welding Institute, Kyiv, Ukraine) with parameters: 66 kHz HFECW, three modes of 10–12 Volts (V), 12–14 V and 14–16 V. The eyes were then enucleated after 1 hour and 3‐, 7‐, 14‐ and 30‐days. Tissue changes were analysed using haematoxylin–eosin staining and light microscopy, and compared to the control eyes. Results: In all treated eyes the monopolar HFECW induced an increased tissue adhesion in the area of electrode application, which strengthened with time. The retina responded by apparent destruction of rods, cones, loss of bipolar, amacrine, horizontal and ganglion cells, development of cysts and migration of RPEs. The choroid showed damage and migration of melanocytes. By 30 days, a ​​tissue thinning with partial cell regeneration and connective tissue degeneration were apparent. Amplification of the voltage from 10 to 16 V caused a shift from active exudation without significant tissue damage to acute retinal necrosis, respectively. The nearby lying retinal layers and vitreous remained intact. Conclusions: Application of HFECW with suprachoroidal approach induced chorio‐retinal adhesion in 1 hour after the treatment, which strengthened within first weeks after the surgery. Implementation of HFECW as an alternative method to treat retinal tears in eyes with retinal detachment could reduce the need for endotamponade and the risks of its possible complications.

Selection and improvement of the method and tool for restoring the anatomical integrity of the retina after its detachment

“…The use of high-frequency electrocoagulation of the retina with suprachoroidal access and a tool with our chosen parameters in an experiment on animals [41] showed high adhesion in the area of application of the electrode, rapid (within an hour) formation of a strong adhesion, which further strengthened over time. Meanwhile, the destruction of rods and cones, the development of cysts, the loss of bipolar, amacrine, horizontal and ganglion cells (Fig.…”

“…In my own research, the method was developed in the form of the use of an electrocoagulation tool with a gold hemispherical tip of 25 gauge, connected to a modified EK-300M1 generator (Kyiv, (Fig. 1) with the following electrical generation parameters: frequency 66 kHz, voltage 10-16 V, current 0.1 A [41]. The selection of parameters of the new tool is the result of long-term research and modeling of thermal processes in the tool and tissues of laboratory animals with the aim of creating a reliable chorioretinal adhesion in a short time after surgical intervention with minimal thermal tissue damage.…”

Застосування Електрокоагуляції При Вітректомії У Хворого З Відшаруванням Сітківки

“…Експерименти на тваринах дали багатообіцяючі результати, продемонструвавши швидке утворення адгезії в області застосування електрода, що зазвичай відбувається протягом години. Крім того, ця адгезія має тенденцію до посилення з часом [9]. Ці висновки підвищують перспективу застосування цієї методики в хірургічних умовах, зокрема для лікування випадків кровотечі під час таких процедур, як розрив артерії сітківки або склеротомія на початку операції.…”