Impression cytology in assessing the dynamics of corneal regeneration after acid burn treated with biostimulating films

Abstract

Introduction. Chemical burns of the cornea of acid etiology represent one of the most challenging pathologies in veterinary ophthalmology, often leading to irreversible vision loss. The high prevalence of eye injuries in agricultural and domestic animals, as well as the tendency of the process toward chronization and secondary infection, necessitate the search for new effective and safe therapeutic agents devoid of the disadvantages of existing drugs (presence of antibiotics, high cost). A promising direction is the development of prolonged-release dosage forms based on biogenic stimulators.
Aim. To study the cytological processes of corneal regeneration in rabbits after experimental acid burn against the background of the application of ophthalmic medicinal films (OMF) based on a biostimulator (BSB) from bovine brain tissue.
Materials and Methods. The experiment was performed on 30 sexually mature rabbits of the Gray Giant breed, divided into two equal groups. Animals of the first group received daily applications of OMF based on BSB after burn modeling; animals of the second group served as controls (without treatment). Corneal impression smears were obtained on days 3, 7, 14, 21, and 28, stained with azure-eosin according to the Romanowsky-Giemsa method, and examined by light microscopy.
Results. We established that the application of OMF based on BSB promotes a regular sequence of wound healing phases: acute inflammation (days 3–7) is followed by proliferation (day 14), culminating in the phase of epithelial differentiation and maturation by days 21–28. Cytologically, this was expressed in a reduction of dystrophic changes, an increase in the size of epithelial cell nuclei, normalization of cellular composition, and complete disappearance of inflammatory cells by the end of observation. In the control group, a protracted course with chronization of inflammation, massive microbial contamination (Streptococcus, Corynebacterium, Bacillus, Streptobacillus), persistence of neutrophilic infiltration, and absence of signs of complete regeneration by day 28 were noted.
Conclusion. Ophthalmic medicinal films based on BSB possess pronounced regenerative potential, arrest inflammation, reduce the risk of secondary infection, and can be recommended for further study as a therapeutic agent for chemical corneal burns in veterinary practice.