Using ultraviolet corneal crosslinking for the treatment of corneal ulcers and other corneal pathologies in animals

Purpose. To study the effects of corneal collagen cross-linking (CCL) using ultraviolet-A (UVA) irradiation with riboflavin on the eye’s anterior segment structures in corneal ulcers and other keratopathies in animals.

Material and methods. The study involved 26 animals (39 eyes) — 10 cats, 10 dogs, and 6 horses with ulcers, corneal staphyloma, dry and autoimmune keratoconjunctivitis. Examination included slit-lamp biomicroscopy, ophthalmoscopy (in cases of transparent cornea), tear production test, and staining the eye surface with vital dyes. CCL was performed using UVA radiation of LEDs with a fiber optic output (wavelength 370 nm, radiation power 3 mW/cm2) combined with 0.1 % riboflavin instillation according to the protocol we developed, which specifies various numbers and durations depending on the diagnosis and therapeutic effect desired.

Results. Restoration of the shape and transparency of the cornea, relief of anterior eye inflammation, and normalization of tear production occurred much sooner than using traditional treatment. The restoration of vision occurred 2 to 3 months earlier in eyes with corneal staphyloma; more than 4 to 5 months earlier in eyes with keratoconjunctivitis; no relapses were noted in eyes with ulcerative processes, and the restoration of the function of stratified squamous epithelium was achieved within 2 or 3 weeks.

Conclusions. The inclusion of modified UFA-based CCL in the treatment scheme of corneal ulcers and staphylomas as well as dry and autoimmune keratoconjunctivitis enables a high therapeutic effect of anterior eye structure restoration. In future, the results obtained could serve as basis for using the developed technology in the treatment of similar eye pathologies in humans. 

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